DE102019204824A1 - Method and device for determining the relative speed between an object and a detector - Google Patents

Abstract

With regard to a particularly simple and reliable determination of the relative speed between an object and a detector (1) with structurally simple means, a method for determining the relative speed between an object and a detector (1) is specified, with a relative movement between the object and the Detector (1) can take place in one direction of movement, the object having at least two detection elements (2, 3) which have a different reflectance spectrum relative to a predeterminable region (4) of the object and different from one another, at least one of the detection elements (2, 3) adjoins the area (4), the detection elements (2, 3) during the possible relative movement and during a predeterminable duration (Δt) of an image recording by the detector (1) by means of an illumination device with a first light with a first wavelength ( 6) and - during a specifiable part of this resulting duration of an illumination with the first light - additionally be illuminated with a second light with a second wavelength (7) different from the first wavelength (6).

Description

The invention relates to a method for determining the relative speed between an object and a detector, wherein a relative movement between the object and the detector can take place in one direction of movement. The present invention also relates to corresponding devices for carrying out such methods.

Methods and devices of the type mentioned are known from practice and exist in different embodiments. Such methods and devices are used, in particular, in industrial areas in which objects moving relative to a detector must be monitored, preferably in an automated manner.

For example, from the EP 0 532 169 A1 a method is known in which the relative speed between an object on a surface and a detector can be determined with a CCD array. The relative speed is determined on the basis of the sequence of individual image recordings.

Furthermore, from the EP 1 729 086 A1 a method for image processing is known, wherein relative speeds between an object and a detector are determined.

The known methods for determining the relative speed are well suited for the applications described in the above prior art. However, in many applications today it is necessary to achieve a particularly high level of reliability when determining the relative speed. The methods known from the prior art are only suitable to a limited extent for this purpose, since, in particular if one of the individual measuring components in the image processing chain fails, it cannot immediately be determined that a speed measurement is faulty. The aim here is to increase the reliability of the determination of the relative speed.

The present invention is therefore based on the object of specifying a method and a device for determining the relative speed between an object and a detector, according to which a particularly reliable determination of the relative speed between an object and a detector is made possible with structurally simple means.

According to the invention, the above object is achieved by a method with the features of claim 1 and, alternatively, by a method with the features of claim 9 and by devices with the features of claims 20 and 21.

Thereafter, the method according to the invention forms a method for determining the relative speed between an object and a detector, wherein a relative movement between the object and the detector can take place in one direction of movement,
wherein the object has at least two detection elements which have a remission spectrum that is different relative to a predeterminable area of the object and that differs from one another, with at least one of the detection elements adjoining the area,
wherein the detection elements during the possible relative movement and during a predeterminable duration of an image recording by the detector by means of an illumination device with a first light with a first wavelength and - during a predeterminable part of a duration of illumination with the first light resulting therefrom - additionally with a second Light is illuminated with a second wavelength different from the first wavelength,
wherein the wavelengths are selected such that at least one first detection element of the detector is dark or light when illuminated with the first wavelength and also dark or light when illuminated with the second wavelength, at least one further second detection element when illuminated with the first wavelength dark or light and with additional illumination with the second wavelength light or dark and the area can be detected both with illumination with the first wavelength and with additional illumination with the second wavelength light or dark with correspondingly low or high brightness,
wherein, in the image recording generated in this way, a brightness curve that is dependent on the remission spectra of the area and the detection elements and on the different wavelengths of the illuminations with decreasing and / or increasing brightnesses in the possible direction of movement is detected by the detector, and
wherein based on a proportionality of a spatial width of a decreasing or increasing section of the brightness curve to the relative speed and taking into account a Illumination duration of the first light and / or an illumination duration of the second light, the relative speed is determined and / or
wherein based on a proportionality of a distance between two constant sections and / or a distance between centers of two constant sections and / or a width of a peak between two constant sections of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light the relative speed is determined.

Furthermore, the method according to the invention forms a method for determining the relative speed between an object and a detector, wherein a relative movement between the object and the detector can take place in one direction of movement,
wherein the object has at least two detection elements which have a remission spectrum that is different relative to a predeterminable area of the object and that differs from one another, with at least one of the detection elements adjoining the area,
wherein the detection elements are alternately illuminated with light of different wavelengths during the possible relative movement and during a prescribable duration of an image recording by the detector by means of an illumination device in a prescribable sequence and a prescribable respective illumination duration,
wherein the wavelengths are selected such that a first detection element of the detector is dark or light when illuminated with a first wavelength and also dark or light when illuminated with a second wavelength different from the first wavelength, and a second detection element when illuminated with the the first wavelength dark or light and, in the case of an illumination with the second wavelength, light or dark and the area both in an illumination with the first wavelength and in an illumination with the second wavelength light or dark with correspondingly low or high brightness,
wherein in the image recording generated in this way, a brightness curve that is dependent on the remission spectra of the area and the detection elements and on the different wavelengths of the illuminations is detected by the detector with decreasing and / or increasing brightnesses in the possible direction of movement, and
wherein based on a proportionality of a spatial width of a decreasing or increasing section of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light, the relative speed is determined and / or
wherein based on a proportionality of a distance between two constant sections and / or a distance between centers of two constant sections and / or a width of a peak between two constant sections of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light the relative speed is determined.

Furthermore, according to claim 20, a device for performing a method for determining the relative speed between an object and a detector is specified, wherein a relative movement between the object and the detector can take place in one direction of movement,
wherein the object has at least two detection elements which have a remission spectrum that is different relative to a predeterminable area of the object and that differs from one another, with at least one of the detection elements adjoining the area,
wherein the detection elements during the possible relative movement and during a predeterminable duration of an image recording by the detector by means of an illumination device with a first light with a first wavelength and - during a predeterminable part of a duration of illumination with the first light resulting therefrom - additionally with a second Light can be illuminated with a second wavelength different from the first wavelength,
wherein the wavelengths are selected such that at least one first detection element of the detector is dark or light when illuminated with the first wavelength and also dark or light when illuminated with the second wavelength, at least one further second detection element when illuminated with the first wavelength dark or light and with additional illumination with the second wavelength light or dark and the area can be detected both with illumination with the first wavelength and with additional illumination with the second wavelength light or dark with correspondingly low or high brightness,
wherein, in the image recording generated in this way, a brightness curve that is dependent on the remission spectra of the area and the detection elements and on the different wavelengths of the illuminations with decreasing and / or increasing brightnesses in the possible direction of movement can be detected by the detector, and
wherein the relative speed can be determined and / or based on a proportionality of a spatial width of a decreasing or increasing section of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light
wherein based on a proportionality of a distance between two constant sections and / or a distance between centers of two constant sections and / or a width of a peak between two constant sections of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light the relative speed can be determined.

Finally, according to claim 21, a device for performing a method for determining the relative speed between an object and a detector is specified, wherein a relative movement between the object and the detector can take place in a direction of movement,
wherein the object has at least two detection elements which have a remission spectrum that is different relative to a predeterminable area of the object and that differs from one another, with at least one of the detection elements adjoining the area,
wherein the detection elements can be illuminated alternately with light of different wavelengths during the possible relative movement and during a prescribable duration of an image recording by the detector by means of an illumination device in a prescribable sequence and in a prescribable respective illumination duration,
wherein the wavelengths are selected such that a first detection element of the detector is dark or light when illuminated with a first wavelength and also dark or light when illuminated with a second wavelength different from the first wavelength, and a second detection element when illuminated with the first wavelength dark or light and, when illuminated with the second wavelength, light or dark, and the area can be detected both with illumination with the first wavelength and with illumination with the second wavelength light or dark with correspondingly low or high brightness,
wherein, in the image recording generated in this way, a brightness curve that is dependent on the remission spectra of the area and the detection elements and on the different wavelengths of the illuminations with decreasing and / or increasing brightnesses in the possible direction of movement can be detected by the detector, and
wherein the relative speed can be determined and / or based on a proportionality of a spatial width of a decreasing or increasing section of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light
wherein based on a proportionality of a distance between two constant sections and / or a distance between centers of two constant sections and / or a width of a peak between two constant sections of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light the relative speed can be determined.

In the manner according to the invention, it was first recognized that a particularly reliable determination of the relative speed between an object and a detector with the aid of predeterminable illumination during the possible relative movement and during an image recording by the detector is possible with structurally simple means. The expression "possible relative movement" and "possible direction of movement" means that the determination of the relative speed between an object and a detector also covers the case in which the relative speed is zero, i.e. there is no relative speed in any direction of movement. If there is a relative movement, this then takes place in the "possible direction of movement". The term “relative speed” in this document therefore also includes the case in which the relative speed is equal to zero.

Specifically, the object has at least two detection elements for this purpose, which have a remission spectrum that is different relative to a predeterminable region of the object and also different from one another. In other words, both the predeterminable area and the at least two detection elements have remission spectra or colors that differ from one another. At least one of the detection elements adjoins the area. During the possible relative movement and during a predefinable duration of an image recording by the detector, the detection elements are illuminated with a first light with a first wavelength and - during one specifiable part of the resulting duration of an illumination with the first light - additionally illuminated with a second light with a second wavelength different from the first wavelength.

The wavelengths are selected in such a way that at least one first detection element of the detector is dark when illuminated with the first wavelength and also dark when illuminated with the second wavelength, at least one further second detection element dark when illuminated with the first wavelength and dark with additional Illumination with the second wavelength bright and the area can be detected both with illumination with the first wavelength and with additional illumination with the second wavelength brightly with a correspondingly low or high brightness. As an alternative to this, the wavelengths are selected such that at least one first detection element of the detector is bright when illuminated with the first wavelength and also bright when illuminated with the second wavelength, at least one further second detection element is bright when illuminated with the first wavelength and when additional illumination with the second wavelength dark and the area can be detected both with illumination with the first wavelength and with additional illumination with the second wavelength dark with correspondingly low or high brightness. In this context, light or dark means intensities of the brightness that can be differentiated by the particular detector used due to its sensitivity, so that a contrast between the illuminated detection elements and the area can be perceived by the detector with suitable lighting. For example, a green detection element illuminated with a red wavelength appears dark, whereas this green detection element appears light or lighter with additional illumination with a green wavelength.

In the image recording generated in this way, a brightness curve that is dependent on the reflectance spectra of the area and the detection elements and on the different wavelengths of the illuminations with decreasing and / or increasing brightnesses in the possible direction of movement is detected by the detector. The brightnesses detected by the detector are integrated during the image recording period. In this respect, a moving darkly detected detection element, which is arranged on a lightly detected area, creates a section with decreasing brightness in the possible direction of movement.

Based on a proportionality of a spatial width of this decreasing or, in another case constellation, increasing section of the brightness curve to the relative speed, the relative speed is then determined taking into account an illumination duration of the first light and / or an illumination duration of the second light.

As an alternative or in addition to this, based on a proportionality of a distance between two constant sections and / or a proportionality of a distance from centers of two constant sections and / or a proportionality of a width of a peak between two constant sections of the brightness curve to the relative speed and taking into account a lighting duration of the first light and / or an illumination duration of the second light determines the relative speed. There are therefore different options for determining the relative speed, with decreasing or increasing sections or edges of the brightness curve and / or constant sections of the brightness curve and / or a peak in the brightness curve being taken into account. When the constant sections are taken into account, on the one hand the distance between the constant sections and on the other hand or additionally the distance from the centers of the constant sections can be taken into account. If a peak in the brightness curve between two constant sections is taken into account, this peak can point in the direction of greater brightness or in the direction of lower brightness. In any case, the width of such a tip between two constant sections is relevant for determining the relative speed and not the direction in which the tip points.

In the alternative method according to claim 9, the detection elements are illuminated differently from the method according to claim 1, the detection elements alternating with light during the possible relative movement and during a predeterminable duration of an image recording by the detector by means of an illumination device in a predeterminable sequence and predeterminable respective illumination duration different wavelengths are illuminated. There is therefore an alternation of the illumination with light of different wavelengths and not a superimposition of one light with a second light of different wavelength as in the method according to claim 1.

The wavelengths are selected in such a way that the detector detects a first detection element dark when illuminated with a first wavelength and also dark when illuminated with a second wavelength different from the first wavelength. Furthermore, a second Detection element detected dark when illuminated with the first wavelength and light when illuminated with the second wavelength. Finally, the area is detected both with an illumination with the first wavelength and with an illumination with the second wavelength brightly with a correspondingly low or high brightness. Alternatively, the wavelengths can be selected such that a first detection element of the detector is bright when illuminated with a first wavelength and also bright when illuminated with a second wavelength different from the first wavelength, and a second detection element is bright when illuminated with the first wavelength and in the case of illumination with the second wavelength dark and the area is detected both in the case of illumination with the first wavelength and in the case of illumination with the second wavelength dark with correspondingly low or high brightness. In this method, too, light or dark means intensities of the brightness that can be differentiated by the particular detector used due to its sensitivity, so that a contrast between the illuminated detection elements and the area can be perceived by the detector with suitable illumination.

As in the case of the method according to claim 1, a brightness profile with decreasing and / or increasing brightnesses in the possible direction of movement is detected by the detector in the image recording generated thereby. Furthermore, the relative speed is finally determined in the same way as in the method according to claim 1, so that reference may be made to the corresponding statements on the method according to claim 1 with regard to this detection of the brightness profile and the determination of the relative speed. The methods according to claim 1 and claim 9 are the same in this regard.

By specifying the illumination with a first light with a first wavelength and additional illumination with a second light with a second wavelength different from the first wavelength during a predeterminable part of a duration of the illumination with the first light and alternatively the specification of the sequence and the respective Illumination duration of the alternating light of different wavelengths within the duration of an image recording by the detector and taking into account the reflectance spectra or the color design of the detection elements and the area, a very specific - expected - brightness curve is generated and detected by the detector, whereby it is further assumed that the level of the relative speed moves in a range that is also expected. The brightness curve actually detected by the detector in a specific application can be compared by means of an evaluation device with the brightness curve expected on the basis of the selected lighting and detection element parameters prevention of a further relative movement between the object and the detector can be taken or the deviation can be displayed. Such a deviation can indicate a malfunction in the image processing, for example in the detector. If no deviation occurs, a very reliable speed measurement can be assumed.

With the method according to the invention and the corresponding devices according to the invention, a particularly reliable determination of the relative speed is possible with structurally simple means, only through suitable lighting and suitable remission spectra or color design of the detection elements and the area.

With regard to an advantageous embodiment of the method according to claim 1, for example, a situation can be taken into account in which a code, in particular a data matrix code or a barcode, is arranged on or on the object, for example for determining the position between the object and the Detector is provided and in a suitable manner, for example by means of the detector, detected or read out or evaluated. In this case it is essential that the lighting of the detection elements does not interfere with or even make a position determination by means of the code. For this purpose, the remission spectra or the color design of the detection elements and the first wavelength and / or the second wavelength can be selected to be coordinated with one another in such a way that the additional illumination of a code - described above - arranged on or on the object with the second wavelength or the first wavelength essentially no change in reflections and / or absorptions generated initially by illuminating the code with the first wavelength or the second wavelength by the code. The aim is to prevent the illumination or additional illumination of the detection elements with the second or the first wavelength from causing a disruption, for example, to a position determination by means of the code.

To avoid, for example, excessive brightening or excessive reflection from one or more elements and / or one or more areas of a code by lighting or additional lighting with the second or first wavelength, one or more elements and / or a or several areas of a code arranged on or on the object, in particular a data matrix code or a bar code, have a portion that absorbs or blocks the second wavelength and / or the first wavelength. Here too, for example, it can be taken into account that a position determination of the relative position between an object and a detector to be carried out by means of such a code is not disturbed by lighting or additional lighting of the detection elements. In particular, an area designed in white would initially become even brighter with red lighting by adding additional green lighting than with red lighting only.

Depending on the application, the time of the start and / or the duration of the illumination with the second light can or can be specified. In this way, different brightness gradients - depending on requirements - can be generated. The relative speed must then be determined as a function of the brightness curve. Such a specification of the point in time of the start and / or the duration of the illumination with the second light can preferably take place by means of a control device and more preferably randomly. An evaluation of the brightness curve can be carried out according to the lighting parameters, which are preferably generated randomly, by means of a suitable evaluation device.

In a further advantageous manner, the direction of movement can be determined, taking into account the shape of the brightness profile and / or the point in time of the start and / or the duration of the illumination with the second light. Use can be made here of the fact that the brightness curve has two different shapes for the same illumination pattern from first and second light for the same object, depending on the direction in which the object is moving. For example, with an optical axis of the detector arranged perpendicular to the possible direction of movement, a reliable distinction can be made as to whether the object is moving, for example, from left to right or from right to left. For this purpose, known brightness curves that result when known wavelengths and detection elements are present, for which the respective direction of movement of the object is also known, can be used for comparison with currently detected brightness curves.

Depending on the application, the first light and / or the second light can alternatively or additionally be switched on, switched on or switched off with increasing and / or decreasing intensity. A desired brightness curve can also be generated through the selection of these parameters in order to be able to reliably determine the relative speed from this.

In a further advantageous manner, the duration of the illumination with the first wavelength can be specified. In other words, the duration of the entire illumination with the first and the additional second wavelength corresponds to the duration of the illumination with the first wavelength.

As further parameters that can influence the course of brightness in a desired or required manner, an image scale implemented during image recording and / or a blurring caused by an objective of the detector during image recording can advantageously serve. These parameters can be specified in order to generate a desired brightness curve.

In the method according to claim 9, it can likewise advantageously be taken into account that a possible determination of the position between the object and the detector is not disturbed by means of a code as already described above. With regard to the problem in this regard, reference may be made to the corresponding statements on the method according to claim 1. With regard to the consideration of this boundary condition in the method according to claim 9, the reflectance spectra or the color design of the detection elements and the first wavelength and / or the second wavelength can be selected to be coordinated with one another in such a way that the illumination of the detection elements changes from light with the first wavelength to Light with the second wavelength or, conversely, essentially no change in reflections initially generated by the illumination of a code arranged on or on the object, in particular a data matrix code or a barcode, with the first wavelength or the second wavelength and / or Causes absorptions. In this case, for example, a first and a second wavelength can be selected which are so close to one another that a reflection and / or absorption of a code does not change when changing between the two wavelengths. However, the two wavelengths must differ from one another so far that the desired change between light and dark with regard to the detection of the detection elements is guaranteed.

In a particularly simple embodiment of the method according to claim 9, the wavelength of the illumination can be changed from the first wavelength to the second wavelength after half the duration of the image recording. The detection elements are first illuminated with light of a first wavelength and then with light of a second wavelength different from the first wavelength. Such a change in the wavelengths can also take place, for example, after a third of the duration of the image recording or only after two thirds of the duration of the image recording. When choosing the individual lighting duration of the lights with different wavelengths, the respective application must be taken into account.

With the method according to the invention and the device according to the invention, it is also possible in a particularly advantageous manner that the direction of movement is determined taking into account the shape of the brightness curve and the sequence of the wavelengths of the illumination. Use can be made of the fact that, given the same sequence of the wavelengths of the illuminating light, the brightness curve has two different shapes for the same object, depending on the direction in which the object is moving. For example, with an optical axis of the detector arranged perpendicular to the possible direction of movement, a reliable distinction can be made as to whether the object is moving, for example, from left to right or from right to left. Thus, with the method according to the invention and the device according to the invention, it is not only possible to reliably determine the relative speed, but also to reliably determine the direction of movement. For this purpose, known brightness curves that result when known wavelengths and detection elements are present, for which the respective direction of movement of the object is also known, can be used for comparison with currently detected brightness curves.

Depending on the application, the first light and / or the second light can alternatively or additionally be switched on, switched on or switched off with increasing and / or decreasing intensity. A desired brightness curve can also be generated through the selection of these parameters in order to be able to reliably determine the relative speed from this.

As further parameters that can influence the course of brightness in a desired or required manner, an image scale implemented during image recording and / or a blurring caused by an objective of the detector during image recording can advantageously serve. These parameters can be specified in order to generate a desired brightness curve.

In the following, advantageous embodiments of both methods according to claims 1 and 9 as well as the corresponding claimed devices according to claims 20 and 21 are explained.

In an advantageous manner, a monochrome camera can be used as a detector, it being possible to use a camera with a pixel sensor. With such a pixel sensor, the course of brightness can be recorded - preferably in the direction of movement - particularly simply - pixel by pixel - and determined with regard to its width or length. In a further advantageous manner, the pixel sensor can be designed as a CMOS sensor or CCD sensor or as a line sensor.

With regard to a particularly clearly definable and easily generated brightness curve, the detection elements can be arranged on, on or in the object adjacent to one another and / or one inside the other. Such detection elements can, for example, be printed on the object or integrated into the object.

Furthermore, with a view to generating a particularly simple brightness curve, the detection elements can be arranged adjacent to one another in the direction of movement. This enables reliable detection of the brightness profile.

In principle, the detection elements can have very different shapes and contours, provided that a suitable color difference or contrast to the adjacent area can be realized. In a particularly simple manner, the detection elements can have a rectangular or round contour. As an alternative to this, the detection elements can also have a different polygonal or polygonal contour, this not necessarily having to be a contour that is symmetrical in any way. For example, an edge profile of the detection elements that is inclined to the direction of movement can also be implemented be. The specific shape of the detection elements may need to be taken into account in a suitable manner when determining the relative speed. In a further advantageous manner, the detection elements can be an element of a code, in particular a data matrix code or a barcode. Such codes are used, for example, when determining the position of objects moving relative to a detector in the industrial sector, the codes being attached to the objects. Such codes are characterized by clear contrasts to surrounding or bordering areas in order to enable reliable image recording and evaluation of the codes.

As an alternative to a flat configuration of the detection elements as described above with, for example, a rectangular contour, the detection elements can be implemented as linear or almost linear detection elements which extend in the direction of movement and which can be formed from individual pixels. In the case of linear detection elements, a brightness curve that results when the method is carried out will also be linear or almost linear, and here too - depending on the detector used - a brightness curve can result from individual pixels. The length of this linear brightness curve is in turn proportional to the relative speed, the relative speed being able to be determined here too, taking into account the recording time.

In a preferred embodiment of the teaching according to the invention, the area can be implemented as a light or white or as a dark or black area or background. As an alternative or in addition to this, the range can have a high or a low level of remission for at least one specifiable spectral range and / or for at least one wavelength. In this way, a reliable differentiation of the area of detection elements designed in different colors or of detection elements with different reflectance spectra can be realized.

With regard to a particularly reliable determination of the relative speed, the duration of the image recording can be specified in such a way that the object or the detection elements do not move or move out of a viewing window of the detector during the duration of the image recording. On the other hand, it is advantageous if the object - when using a pixel sensor - moves relatively at least along a plurality of pixels in order to enable a sufficient width of the brightness curve and thus a safe and reliable determination of the relative speed.

The detection element is preferably printed several times on a code tape or tape serving as an object, so that it can be seen several times in the field of vision of the detector or sensor, so that detection elements at the edge do not result in the system or device failing.

At this point, it should be noted that throughout the document, the terms “wavelength” and “illumination wavelength” can mean not only an isolated wavelength but also a wavelength range or a combination of different individual wavelengths and / or wavelength ranges in the entire electromagnetic spectrum. In this respect, the term “wavelength” or “illumination wavelength” is synonymous with one or more individual wavelengths and / or one or more wavelength ranges. There is no restriction to the visible wavelength range when using the term “color”. The entire electromagnetic spectrum is also included here. When using the term “color”, this can be understood as a mere exemplary designation of a section of the electromagnetic spectrum that relates to the visible wavelength range.

• 1 in einer schematischen Darstellung ein Sichtfenster eines bei einem Ausführungsbeispiel des erfindungsgemäßen Verfahrens verwendeten Detektors sowie den Detektor, wobei zwei Detektionselemente im Sichtfenster sichtbar sind,
• 2 in drei übereinanderliegenden schematischen Darstellungen, bei a) ein nach unten aufgetragener zeitlicher Ablauf während einer Bildaufnahme, wobei links neben den Detektionselementen die Beleuchtungsreihenfolge mit zunächst einer roten und nach der Hälfte der Dauer der Bildaufnahme blauen Beleuchtung gezeigt ist, bei b) die Helligkeit, die ein monochromer Detektor während der Bildaufnahme detektiert, und bei c) in einem Diagramm die während der Dauer der Bildaufnahme aufgenommene Helligkeit B entlang der Bewegungsrichtung x, wobei bei dieser Darstellung noch keine Relativbewegung zwischen dem Objekt und dem Detektor stattgefunden hat,
• 3 in drei schematischen Darstellungen in den Teilen a), b) und c) dieselbe Situation wie in 2, jedoch bei einer erfolgten Relativbewegung während der Dauer der Bildaufnahme, wobei sich das Objekt nach rechts, d.h. in positiver x-Richtung bewegt hat,
• 4 in einem Diagramm einen typischen Helligkeitsverlauf bei Betrachtung eines Detektionselements gemäß 3,
• 5 in einer schematischen Darstellung vier Situationen jeweils in Bereichen I., II., III. und IV., wobei die Darstellungen gemäß den Teilen a), b) und c) den Darstellungen in den 2 und 3 entsprechen und wobei jeweils Relativbewegungen nach links oder nach rechts bei zunächst roter und nach der Hälfte der Aufnahmedauer blauer Beleuchtung in den Bereichen I. und II. und zunächst blauer Beleuchtung und dann nach der Hälfte der Aufnahmedauer roter Beleuchtung in den Bereichen III. und IV. gezeigt sind,
• 6 in einer schematischen Darstellung die beiden Situationen gemäß den Bereichen III. und IV. aus 5, wobei Abschnitte konstanter Helligkeit und eine Spitze im Helligkeitsverlauf für die Bestimmung der Relativgeschwindigkeit spezifiziert sind,
• 7 bis jeweils in drei schematischen Darstellungen in den Teilen a), b) und c) 23 unterschiedliche Situationen hinsichtlich der Bewegung der Detektionselemente bzw. des Objekts nach rechts oder links, hinsichtlich einer Halbierung der Bewegungsgeschwindigkeit, hinsichtlich des Abbildungsmaßstabs, hinsichtlich einer durch das Objektiv verursachten Unschärfe und hinsichtlich der Farbe, des Zeitpunkts und der Dauer der Beleuchtungen der Detektionselemente,
• 24 in einer schematischen Darstellung eine Anordnung zur Überwachung einer Auswerteeinheit mit einer Beleuchtungseinheit, einer Bildauswertung und einer Steuerung für die Beleuchtung,
• 25 in schematischen Darstellungen vier unterschiedliche Anordnungen von Detektionselementen,
• 26 vier Situationen einer Anordnung aus Data Matrix Codes und Detektionselementen in unterschiedlichen Beleuchtungssituationen,
• 27 in einer schematischen Darstellung drei Absorptionsspektren mit möglichen Beleuchtungsfarben,
• 28 bis in jeweils einer schematischen Darstellung die Absorptionsspektren 30 aus 27 mit einer möglichen Beleuchtung und der entsprechenden Reflexion oder Absorption der Farben Orange, Cyan bzw. Gras,
• 31 in einer tabellarischen Darstellung das Reflexions- und Absorptionsverhalten der Farben Orange, Cyan und Gras bei Beleuchtung mit unterschiedlichen Blau- und Rottönen,
• 32 jeweils in drei schematischen Darstellungen in den Teilen a), b) und c) das Absorptions- und Reflexionsverhalten der Farben Orange, Cyan, Gras und Schwarz bei Beleuchtung mit Blautönen und Rottönen ohne Bewegung der Farbelemente,
• 33 jeweils in drei schematischen Darstellungen vier unterschiedliche Situationen von Detektionselementen bei unterschiedlicher Beleuchtung und jeweils einer Bewegung nach rechts,
• 34 die vier Situationen gemäß 33, aber mit einer Bewegung nach links und
• 35 in sechs schematischen Darstellungen die Abbildung von Detektionselementen im Stillstand, bei Bewegung nach links und Bewegung nach rechts mit unterschiedlichen Beleuchtungsmustern.

There are now various possibilities for designing and developing the teaching of the present invention in an advantageous manner. For this purpose, reference is made, on the one hand, to the subordinate claims and, on the other hand, to the following explanation of preferred exemplary embodiments of the method according to the invention and the devices according to the invention with reference to the drawing. In connection with the explanation of the preferred exemplary embodiments with reference to the drawing, generally preferred configurations and developments of the teaching are also explained. Show in the drawing

• 1 in a schematic representation a viewing window of a detector used in an exemplary embodiment of the method according to the invention and the detector, two detection elements being visible in the viewing window,
• 2 in three superimposed schematic representations, at a) a downwardly plotted time sequence during an image recording, with the lighting sequence being shown to the left of the detection elements with initially a red and after half the duration of the image recording blue lighting, with b) the brightness that a monochrome detector is detected during the image recording, and at c) in a diagram the brightness recorded during the duration of the image recording B. along the direction of movement x, whereby in this representation no relative movement has yet taken place between the object and the detector,
• 3 in three schematic representations in parts a), b) and c) the same situation as in 2 , but if there was a relative movement during the duration of the image recording, with the object moving to the right, ie in the positive x-direction,
• 4th in a diagram a typical brightness curve when viewing a detection element according to FIG 3 ,
• 5 in a schematic representation four situations each in areas I., II., III. and IV., the representations according to parts a), b) and c) to the representations in 2 and 3 and with relative movements to the left or to the right with initially red and after half of the exposure time blue lighting in areas I. and II. and initially blue lighting and then after half the exposure time red lighting in areas III. and IV. are shown,
• 6th in a schematic representation the two situations according to areas III. and IV. from 5 , where sections of constant brightness and a peak in the brightness curve are specified for determining the relative speed,
• 7th up to each in three schematic representations in parts a), b) and c) 23 different situations with regard to the movement of the detection elements or the object to the right or left, with regard to halving the movement speed, with regard to the reproduction scale, with regard to a blurring caused by the lens and with regard to the color, the time and the duration of the illumination of the detection elements,
• 24 in a schematic representation an arrangement for monitoring an evaluation unit with a lighting unit, an image evaluation and a control for the lighting,
• 25th four different arrangements of detection elements in schematic representations,
• 26th four situations of an arrangement of data matrix codes and detection elements in different lighting situations,
• 27 a schematic representation of three absorption spectra with possible lighting colors,
• 28 up to in each case a schematic representation of the absorption spectra 30th out 27 with possible lighting and the corresponding reflection or absorption of the colors orange, cyan or grass,
• 31 in a table the reflection and absorption behavior of the colors orange, cyan and grass when illuminated with different shades of blue and red,
• 32 in three schematic representations in parts a), b) and c) the absorption and reflection behavior of the colors orange, cyan, grass and black when illuminated with blue tones and red tones without movement of the color elements,
• 33 each in three schematic representations four different situations of detection elements with different lighting and one movement to the right,
• 34 the four situations according to 33 , but with a movement to the left and
• 35 In six schematic representations, the mapping of detection elements when stationary, when moving to the left and moving to the right with different lighting patterns.

According to the 1 to 6th is first of all a basic description of how a relative speed can be determined by means of predetermined detection elements and suitable lighting as well as a subsequent image recording and evaluation. This explanation according to the 1 to 6th serves the basic understanding of embodiments of the teaching claimed here, which are based on the 6th subsequent 7-35 is explained by way of example using suitable exemplary embodiments.

1 shows a detector in a schematic representation 1 to determine the relative speed between an object and the detector 1 , the object having two detection elements 2 and 3 having that to an area 4th of the object. The detection element 2 has a turquoise color and the detection element 3 an orange color. The area 4th is trained white. 1 shows the area 4th with the detection elements 2 and 3 in a viewing window 5 of the detector 1 that as monochrome Image pickup is designed in the form of a CMOS sensor. The detection elements 2 and 3 as well as the area 4th have different colors from each other.

During the procedure, the detection elements 2 , 3 during the possible relative movement and during a predefinable duration of an image recording by the detector 1 by means of a lighting device in a specifiable sequence and specifiable respective lighting duration, alternating with light of different wavelengths 6th , 7th illuminated. In the embodiment shown here, the first wavelength corresponds 6th red light and the second wavelength 7th blue light. By choosing the color design or the design with regard to the provided reflectance spectra of the detection elements 2 and 3 as well as the area 4th and the choice of illumination light colors provides a situation whereupon the first detection element 2 due to its turquoise color it appears light under blue lighting and dark under red lighting. With the orange color of the second detection element 3 if the situation is exactly the opposite, according to which this orange detection element 3 appears dark with blue lighting and bright with red lighting.

In the 1 , 2 , 3 and 5 corresponds to the dotted representation of the first detection element 2 a turquoise color and the representation of the second detection element 3 with cross lines of an orange color. The red light of the first wavelength 6th is represented by lines sloping down to the right and the blue light of the second wavelength 7th represented by lines running diagonally to the top right.

2 shows in a schematic representation how the brightness values are determined. A situation is shown in which there is no relative movement between the object and the detector. This includes the case with a relative speed with the value zero. At a) is the timing or the time t applied downward during an image acquisition. Between the arrow of the time sequence and the detection elements 2 and 3 is schematically the illumination color with initially the first wavelength 6th - red light - and then the second wavelength 7th - blue light - shown. To the right is a horizontal section plane through the detection elements 2 and 3 applied over time t down, ie along the t-axis. The color change or wavelength change takes place after half the duration of the duration Δt the image acquisition takes place. In the middle part b) the 2 the brightness that a monochrome image recorder such as the detector is plotted 1 detects, whereby the black area corresponds to the dark perception and the white area with the edge delimitation by a black line corresponds to the light perception by the detector. It can be seen that the detection element is during the first half of the exposure time 2 appears dark and light during the second half of the exposure time. With the detection element 3 the opposite is true. It appears light at first and then dark. The detector integrates the illuminance during the exposure time or the duration of the image recording, so that the brightness recorded by the detector as in the lower part c) of 2 can be determined, the mean value being calculated along the t-axis for each point on the x-axis, which shows the spatial extent along a possible direction of movement.

That means with the detection element 2 in the left area first 0% brightness and then 100% brightness, which results in an average value of 50% brightness, ie (0% + 100% / 2 = 50%. The average value is the same as for the detection element 3 a value of 50%. According to the diagram in c), this results in a brightness curve of the brightness B. of a maximum value, that of the brightness of the white area 4th corresponds to a one section 10 or a distance of 50% constant which is initially transmitted to the detection element 2 and then the detection element 3 corresponds. The brightness curve then rises again to the maximum value, that of the brightness of the area 4th corresponds. The detection elements behave according to b) 2 and 3 so just in opposite directions, after which the first detection element first 2 dark and the second detection element 3 bright and then the first detection element 2 bright and the second detection element 3 be detected dark. The entire course of brightness during the duration of the image recording and the once changing different colored lighting is shown in the diagram at c).

• Die Erkennung der Detektionselemente 2 und 3 durch den Detektor 1 hängt von deren farblicher Gestaltung oder deren Remissionsspektren und von der jeweiligen Beleuchtungswellenlänge ab. In der Realität wird man möglicherweise keine extrem schmalbandigen Beleuchtungen mit nur einer Wellenlänge oder wenigen Wellenlängen zur Verfügung haben. In gleicher Weise wird das von den Detektionselementen 2 und 3 reflektierte Licht nicht nur aus einer Wellenlänge oder einigen wenigen Wellenlängen bestehen. Insoweit sind die Charakterisierungen „dunkel“ und „hell“ ebenfalls relativ zu sehen und eine Unterscheidung dieser beiden Zustände als „dunkel“ oder „hell“ wird vom Auflösungsvermögen des gewählten Detektors abhängen. Grundsätzlich muss ein Remissionsspektrum eines Detektionselements ein Beleuchtungsspektrum der Beleuchtungseinrichtung zumindest teilweise umfassen, um zu einer Wahrnehmung als „hell“ zu führen. Die Farbe oder das Remissionsspektrum des Detektionselements und die Farbe des Beleuchtungslichts müssen in entsprechender Weise ähnlich und aufeinander abgestimmt sein. In umgekehrter Weise soll ein Remissionsspektrum eines Detektionselements ein Beleuchtungsspektrum der Beleuchtungseinrichtung möglichst wenig umfassen, um zu einer Wahrnehmung durch den Detektor als „dunkel“ zu führen. Insoweit führt gemäß dem erläuterten Ausführungsbeispiel eine blaue Beleuchtung einer türkisen Farbe zu einer hellen und eine blaue Beleuchtung einer orangenen Farbe zu einer dunklen Wahrnehmung. Im Ergebnis sind die Farben und jeweiligen Remissionsspektren der Detektionselemente 2 und 3 sowie des Bereichs 4 in geeigneter Weise auf die Wellenlängen 6 und 7 oder auf entsprechende Wellenlängenspektren der abwechselnden Beleuchtung abzustimmen.

To the detection as "dark" and "light" by the detector 1 the following is also carried out:

• The recognition of the detection elements 2 and 3 through the detector 1 depends on their color design or their reflectance spectra and on the respective illumination wavelength. In reality, it is possible that extremely narrow-band lighting with only one wavelength or a few wavelengths will not be available. This is done in the same way by the detection elements 2 and 3 reflected light does not consist of just one wavelength or a few wavelengths. In this respect, the characterizations “dark” and “light” are also to be seen relatively and a distinction between these two states as “dark” or “light” is based on the resolution of the selected The detector. In principle, a reflectance spectrum of a detection element must at least partially include an illumination spectrum of the illumination device in order to lead to a perception as “bright”. The color or the remission spectrum of the detection element and the color of the illuminating light must be similar and matched to one another in a corresponding manner. Conversely, a reflectance spectrum of a detection element should include an illumination spectrum of the illumination device as little as possible in order to lead to a perception by the detector as “dark”. In this respect, according to the exemplary embodiment explained, a blue illumination of a turquoise color leads to a light perception and a blue illumination of an orange color to a dark perception. The result is the colors and the respective remission spectra of the detection elements 2 and 3 as well as the area 4th appropriately to the wavelengths 6th and 7th or to match them to appropriate wavelength spectra of the alternating lighting.

3 shows in three schematic representations a), b) and c) a situation with a relative movement between object and detector 1 for the duration of an image recording. A relative movement takes place along the x-axis to the right in the positive x-direction. The representations in parts a), b) and c) of 3 correspond to the illustrations in parts a), b) and c) of 2 . In part a), the object moving to the right can be recognized by the trapezoidal shape of the detection elements 2 and 3 have formed.

In part b) the 3 are the corresponding intensities of the brightnesses perceived by the detection elements 2 and 3 shown, here also a shift to the right during the time t is recognizable.

The brightness is now in area c) B. plotted along the x-direction. At each point on the x-axis there is an integration of the brightnesses recorded during the duration of an image recording by the detector 1 their precipitation. Compared to the brightness curve in 2 c) there is a kind of broadening of the brightness curve with a falling edge 8th that is based on the maximum value of the brightness, that of the brightness of the area 4th corresponds. Then there is a further section in the positive x-direction 10 or a constant 50% value for a distance and a rising edge in the further course 9 , up to the maximum value of the brightness B. . The gradient pattern is then repeated with a falling edge 8th , one more section 10 or a constant 50% range for a distance and a rising edge 9 up to the maximum value of the brightness, which is again the brightness of the area 4th corresponds. Between the two constant, plateau-like sections 10 with the 50% value is through the rising edge 9 and the subsequent falling edge 8th a peak 11 or a peak section is formed which extends in the direction of increasing brightness B. extends.

4th shows in a diagram the brightness curve with respect to a detection element 2 or 3 according to 3 c) in an isolated illustration. The brightness curve generated during the relative movement is shown here as a function of the location. The brightness B. according to the in 4th The curve shown in the x-direction initially shows its maximum value. This corresponds to the brightness value of the area 4th . Looking further at the curve in the direction of movement along the x-axis, the brightness value increases in the area of the brightness profile along a width d and in the form of a flank 8th or linear ramp down to a minimum of the brightness value. This minimum corresponds to the one section 10 or a distance of 50% constant according to 3 c) . After passing through the constant minimum in the positive x-direction, the brightness increases along a further edge 9 to the maximum value, which is the brightness value of the area 4th corresponds. The width of this further flank 9 corresponds to the width of the first falling edge 8th the curve and thus the distance covered during the relative movement d . The relative speed v can thus be determined using the formula v = d / Δt calculated, where Δt the duration of the image acquisition by the detector 1 is. A determination of the speed can be made both at the in the 3 and 4th shown left flanks or falling flanks 8th as well as right flanks or rising flanks 9 done as both the falling edges 8th as well as the rising flanks 9 the same width d exhibit.

5 shows in schematic representations in the areas I., II., III. and IV. various scenarios with regard to the direction of movement and the lighting sequence. Otherwise the representations shown there correspond to the basic structure 2 and 3 with parts a), b) and c). In particular, the scenario in area II. Corresponds to the scenario 3 . It can be clearly seen that a movement to the left, ie in the negative x-direction, leads to a different brightness curve than a movement to the right in the positive x-direction. However, a reversal of the lighting order with regard to the first wavelength leads 6th and the second wavelength 7th again to a brightness curve that corresponds to the other direction of movement. In other words, the brightness curve of area I. corresponds to that Brightness curve in area IV. And the brightness curve in area II. Corresponds to the brightness curve in area III. Either the direction of movement or the lighting sequence is reversed.

With knowledge of the lighting sequence and knowledge of the color design or reflectance spectra of the detection elements 2 and 3 and the area 4th Thus, not only the speed can be determined, but also the direction of movement can be determined, for which purpose a comparison can be made with known expected spectra by means of an evaluation device.

6th shows in schematic representations the two situations according to areas III. and IV. from 5 , with sections 10 with a constant brightness curve in the x-direction, ie plateaus with constant brightness in the brightness curves according to parts c), and peaks 11 are highlighted in the brightness gradients. Since in some cases the spatial width d the sloping flanks 8th or rising edges 9 Because of the blurriness in digital image processing due to noise and the presence of only a few pixels, it is often difficult to determine, a distance between two constant sections can alternatively or additionally be used to determine the speed 10 and / or a distance D. of centers M. two constant sections 10 and / or a width Q a tip 11 between two constant sections 10 be used. In 6th in addition to these parameters already mentioned, a length L. of a detection element 2 or 3 and a length P of a constant section 10 specified.

Becomes the focus M. of the two sections 10 according to area III. determined, both sections 10 one length each P may have the distance D. the midpoints M. can be calculated as follows: $$\begin{array}{c}\text{D.}=\text{P}/2+\text{d}+\text{d}+\text{P}/2\\ \text{D.}=\text{P}+2*\text{d}\\ \text{D.}=\left(\text{L.}-\text{d}\right)+\left(2*\text{d}\right)\\ \text{D.}=\text{L.}+\text{d}\\ \text{D.}=\text{L.}+\text{v}*\mathrm{\Delta }\text{t}\end{array}$$

It can be seen from this that the distance between the two sections 10 or the distance D. the midpoints M. of sections 10 is linearly dependent on the speed.

Alternatively or in addition to this, the width can also be used Q the top 11 can be determined in the middle of the brightness curve as follows: $$\begin{array}{c}\text{Q}=2*\\ \text{Q}=2*\text{v}*\mathrm{\Delta }\text{t}\end{array}$$

The advantage of considering the width Q the top 11 is that the certain width Q in terms of speed with a factor 2 increases and thus an improved measurement accuracy in comparison with the consideration of the distance between the sections 10 or the distance D. the midpoints M. of sections 10 results.

In the area IV. The distance between the sections 10 or the distance from centers of the sections 10 cannot be used because: $$\begin{array}{c}\text{D.}=\text{P}/2+\text{d}+\text{d}+\text{P}/2\\ \text{D.}=\text{P}+2*\text{d}\\ \text{D.}=\left(\text{L.}-2*\text{d}\right)+2*\text{d}\\ \text{D.}=\text{L.}\end{array}$$

No proportionality to the relative speed can be derived from this.

However, in a situation according to area IV. The width Q the top 11 which are in the middle of the brightness curve between two constant sections 10 can be used again as follows: $$\begin{array}{c}\text{Q}=2*\text{d}\\ \text{Q}=2*\text{v}*\mathrm{\Delta }\text{t}\end{array}$$

According to area III. shows the top 11 towards increasing brightness B. , whereas in area IV. the top 11 towards decreasing brightness B. shows. Since according to area III. a movement to the left and in the area IV. a movement to the right is based, can be from the direction of the tip 11 the direction of the relative speed can be derived.

When carrying out the examples according to 1 to 6th and when carrying out exemplary embodiments of the teaching according to the invention, a suitable, coordinated choice of the color design or design with regard to the reflectance spectra of the detection elements is also important 2 and 3 and the area 4th as well as the wavelengths 6th and 7th or to undertake corresponding wavelength spectra of the illuminating light that illuminates alternately. With these parameters a scenario suitable for the respective application can be generated in order to carry out a more reliable determination of the relative speed - also v = 0 - between an object and a detector. In addition to the colors mentioned above by way of example, any other colors such as, for example, green hues can be used, provided that the detector only provides a sufficient contrast between light and dark perception 1 with appropriate lighting with the different wavelengths 6th and 7th or wavelength spectra is guaranteed. In addition to these parameters, the sequence of lighting and the respective duration of the different lighting can be specified to verify the functionality of a device used. The point in time of the start of an image recording can also be used as an additional or alternative parameter in order to establish a scenario for a suitable image recording, which can then be used to reliably verify the functionality of a detector, for example.

In any case, if the lighting sequence and order of the colors or reflectance spectra of the detection elements are known 2 and 3 of the object, the direction of the relative movement can be determined on the basis of the brightness profile or intensity profile. The speed can be determined from an edge steepness in this brightness profile or intensity profile.

Depending on the detector used, for example a pixel sensor, the in the 2 to 6th The brightness curves shown may be composed of individual pixels or pixel values. A continuous curve can be obtained with a suitable compensation calculation.

In the examples according to 1 to 6th and in the exemplary embodiments of the teaching according to the invention in the following figures is the optical axis of the detector 1 arranged perpendicular to the plane within which the detection elements 2 and 3 or move the object. In further exemplary embodiments, the optical axis of the detector must 1 not necessarily perpendicular to the plane of movement of the detection elements 2 and 3 or of the object. It is also an inclined orientation of the optical axis of the detector 1 relative to the plane of movement of the detection elements 2 and 3 or the object possible. The inclination of the optical axis relative to the plane of movement of the detection elements 2 and 3 or the object must be taken into account when determining the relative speed.

However, the determination of the relative speed does not work or does not work very reliably if the optical axis of the detector 1 runs parallel to or coincides with the direction of movement or within one to the plane of movement of the detection elements 2 and 3 or the object is arranged or extends parallel plane.

The lighting variant described so far is not favorable for all applications. In particular in a case in which, for example, a position determination between detector 1 and the object takes place by means of a code, which is also at least partially colored, can be caused by the exposure of the detection elements 2 , 3 a disturbance of the position determination by the illumination of the detection elements 2 , 3 occur. In other words, unsuitable illumination of the detection elements would result 2 , 3 if necessary change a code content in such a way that a position determination is no longer possible reliably.

According to an exemplary embodiment of the present invention, a lighting variant is provided in which the detection elements 2 , 3 during the relative movement and for a predefinable duration Δt an image recording by the detector 1 by means of a lighting device with a first Light with a first wavelength 6th and - during a predeterminable part of a resulting duration of an illumination with the first light - additionally with a second light with one of the first wavelength 6th different second wavelength 7th be illuminated. Thereby the wavelengths 6th , 7th chosen such that from the detector 1 a first detection element 2 dark with an illumination with the first wavelength and with additional illumination with the second wavelength 7th is also detected dark. Another second detection element 3 becomes with an illumination with the first wavelength 6th dark and with additional lighting with the second wavelength 7th but detected brightly. The area 4th is both with an illumination with the first wavelength 6th as well as with additional illumination with the second wavelength 7th bright with correspondingly high brightness B. detected.

The in 7th The embodiment shown is initially with the wavelength 6th - red light - and after half of the total lighting time also with the wavelength 7th - green light - illuminated. The detection element 2 is black and the detection element 3 grass-colored (a shade of green). With additional lighting with the green light, the grass-colored detection element becomes 3 bright, as in particular the part b) of the 7th is removable. The object or the detection elements 2 and 3 move in 7th to the right, ie in the positive x-direction.

The situation in 8th essentially corresponds to the situation in 7th , being the first wavelength 6th is selected in the blue area of the spectrum. The second wavelength is here too 7th - green light - switched on after half the lighting time, so that the grass-colored or green detection element 3 is then detected bright.

According to the 7th and 8th is in addition to the example according to 5 used red and blue illumination light, another illumination light in the form of green light was added. If a code is usually used with red and blue light in conjunction with a turquoise or cyan, orange, black and white design, the additional green lighting does not change the reflections and / or absorption of the colors of the code, if it is red or illuminated in blue, for example to determine the position between the detector and the object. In this respect, a third lighting color in the form of green lighting in conjunction with a further object color in the form of a grass-colored or green detection element that goes beyond the previously used code colors is suitable for both reliable determination of the relative speed and reliable determination of the position of an object the same system or the same device quasi simultaneously without causing mutual interference by a respectively required lighting sequence. Suitable colors of the detection elements 2 , 3 and / or the code and the lighting are listed in the following table as examples: lighting turquoise orange black Magenta or purple White grass red dark Bright dark Bright Bright dark Red + green dark Bright dark Bright Light * 2 Bright blue Bright dark dark Bright Bright dark Blue + green Bright dark dark Bright Light * 2 Bright green dark dark dark dark Bright Bright

Suitable colors for codes or data matrix codes: turquoise, orange, black and magenta or purple. Suitable colors for speed code: e.g. white, grass, black.

In the table above, the first four colors in the first line correspond to the usual colors of a code. The final color called "grass" is a shade of green called "grass" to avoid confusion with the lighting called "green". In the table it can be seen that adding green to red or blue lighting does not change the reflection behavior or absorption behavior of the turquoise, orange, black and white elements (white becomes even brighter) of a code if it was previously red or blue have been illuminated. Only the grass-colored elements change from dark to light as a result of the additional green lighting. This is a design of the detection elements 2 , 3 as a black detection element 2 and grass-colored detection element 3 in the present color design of a code suitable for an embodiment of the invention.

As an alternative to this, a color design according to the following table could also take place, with the colors turquoise and orange being replaced by cyan and yellow here. The lighting colors remain the same compared to the table above. lighting Cyan yellow black White Magenta or purple grass red dark Bright dark Bright Bright dark Red + green → yellow Bright Bright dark Light * 2 Bright Bright blue Bright dark dark Bright Bright dark Blue + green → cyan Bright Bright dark Light * 2 Bright Bright green Bright Bright dark Bright dark Bright

With the above color design of the detection elements 2 , 3 In connection with the selected lighting colors, it must be taken into account that the colors of the code do not change if they are also illuminated in green. However, you should pay attention to the color white, since a normal white tone appears even brighter with additional green lighting than with only red or blue lighting. A reflection caused by red or blue lighting is essentially doubled by additional green lighting. The color white then appears almost twice as bright as the correspondingly illuminated color orange. When decoding the code, this is unfavorable in terms of position determination, since this results in different brightness values. For a reliable decoding, however, the light values should all be the same as possible.

One solution to this problem would be to use magenta or purple instead of white. Depending on the degree of coverage, this can be set or defined very well with regard to the desired reflection. Magenta or purple does not produce any additional light reflection with additional green lighting and the problem of double brightness with a white tone is eliminated with the alternative use of the color magenta or purple. However, it must be ensured that only white elements of the code are replaced by magenta or purple and not a possible color of the area 4th . The area 4th must remain unchanged with regard to its color design - for example white - in order to maintain the functionality of the decoding and reliable speed and position determination.

As an alternative to changing from white to magenta or purple, the white hue could be provided with an additional blocking component that prevents reflection from additional green lighting. In any case, a further color of a detection element is allowed 2 , 3 only become bright if it is illuminated with the additional wavelength - in the present case green - in order to maintain the functionalities.

In the 7th and 8th situations shown, the illuminating light appears red or blue during the first half of the entire illumination time and in the second half - with additional green lighting - yellow or turquoise.

In the 9 to 23 For the sake of simplicity, red lighting is used as the first light and green lighting is used as the additional second light. Blue lighting is not shown. Different lighting parameters can be varied with a view to reliable functionality of the claimed method. These are the order or the time when the additional lighting is switched on, the duration for how long the additional lighting remains switched on, ramps during which the lighting increases and / or decreases in terms of its intensity and thus switched on and off and the total illumination duration or exposure time of the object. Furthermore, an image scale - 18th to 20th - and a blurring given by the object - 21st to 23 - can be varied.

The 9 to 23 each show three schematic representations in parts a), b) and c) different situations of illumination of the detection elements 2 and 3 .

In the 9 to 11 is a movement of the object with the detection elements 2 and 3 shown to the right. In 9 the additional green lighting is switched on after 50% of the lighting time. At 10 the additional lighting is switched on at the same time as the first light and switched off after 50% of the lighting duration. In 11 becomes the additional green lighting also switched on at the same time as the first lighting, but only switched off again after 75% of the lighting duration. In a corresponding manner, according to part c), the 9 to 11 different brightness gradients.

The 12 to 14th show situations which, in terms of lighting patterns, correspond to the lighting patterns of the situations in 9 to 11 correspond. However, in the situations according to the 12 to 14th instead of moving the object to the right, moving it to the left. Accordingly, there are different reflection situations according to parts b) and different brightness gradients according to parts c).

The 15th to 17th show situations that correspond to the situation in terms of the direction of movement to the left and the lighting pattern 12 to 14th the lighting patterns also correspond to the situations in 9 to 11 correspond. However, in the 15th to 17th the movement to the left compared with the speed in the situations of 12 to 14th only at half the speed. Correspondingly, the course of movement in parts a) is the 15th to 17th not pulled apart as much as in parts a) of the situations in the 12 to 14th .

The situations of 18th to 20th correspond with regard to the lighting pattern, the direction of movement and the speed of movement to the situations according to 15th to 17th . However, in the 18th to 20th a double the distance between the detector and the object and thus a changed image scale compared to the image scale of the 15th to 17th based on. In a corresponding manner, the representations in parts a), b) and c) are compared with the corresponding representations in FIGS 15th to 17th made narrower.

The situations of 21st to 23 basically correspond to the situations in 12 to 14th with a movement to the left. However, a blurring is given here by the lens, which leads to different brightness gradients in the situations according to the 21st to 23 compared with the situations in the 12 to 14th cause.

Depending on the exposure sequence or the choice of time and duration of switching on the additional lighting with the second light, it is not only possible to reliably determine the speed, but also to determine the direction of movement - for example to the right or to the left. For example, the 9 and 13 the same brightness curve in part c), from which the speed can be determined in both cases. This is possible regardless of the knowledge of the underlying lighting pattern. However, if the illumination pattern and thus the time and duration of the switching on of the second wavelength or the second light are also known, then the direction of movement can also be determined from this. According to the 9 and 13 to take into account that in 9 the second light during the second half of the entire lighting period and in 13 is switched on during the first half of the entire lighting period. For example, a conventional evaluation unit in the form of a detector only records a brightness curve, from which the direction cannot be determined without knowledge of the lighting pattern. However, in cooperation with, for example, a controller that is responsible for the sequence of the lighting, the full information regarding speed and direction can be determined. The situation is comparable if the duration of the illumination with the second light is halved and the speed between the detector and the object is doubled. The image recorded by the detector is then identical in both cases. "Speed information" can also be calculated. But only when the exposure time with the second light and / or the start time of the second light are known or taken into account, for example by means of information from an associated controller, can the correct speed be calculated.

A comparable situation as in the 9 and 13 is also in terms of situations 10 and 12 in front. The brightness curve according to parts c) of the figures is identical in both cases, but the direction of movement is opposite.

If the lighting pattern is known - the time of the start and duration of the second lighting with the second light in relation to the total duration of the lighting with the first light - not only the speed but also the direction of movement can be reliably detected and calculated. This makes it possible to monitor an evaluation unit for the course of brightness. In this case, a superimposed control can change the point in time, as it were pseudo-randomly, from which, in particular, the second light is used. The speed determined by the evaluation unit is then compared with the generated lighting pattern. If there is a discrepancy, for example under Taking into account a comparison with previously determined known brightness gradients and lighting patterns, it can be determined that an error has occurred in the recording / calculation chain. Correspondingly, a desired movement between the object and the detector could be stopped for safety reasons. An exemplary arrangement for recording and evaluating corresponding brightness curves is shown in 24 shown.

In principle, the method according to the invention can be extended to other directions of movement - not just in the x direction. In this case, an arrangement of the detection elements 2 and 3 adjusted accordingly. By way of example, the detection elements can be arranged according to 25th have, with four different exemplary embodiments of in two cases round and in two cases square arrangements are shown. The left and right arrangements have a black detection element 2 in the middle, each by a green detection element 3 is framed. The exemplary embodiments in the middle each have a green detection element 3 in the center and outside, these two green detection elements 3 by a black detection element 2 are separated.

26th shows an arrangement of three codes in four schematic representations 104 , 106 and 108 each with overlying detection elements 2 and 3 , wherein the detection element 2 as a black square and the detection element 3 as the detection element surrounding this black square 3 is also realized with a square outer contour. This arrangement is in the upper part of the 26th shown in the unlit state. This arrangement is shown below in three further states, namely with blue, green and blue and at the same time green illumination. With blue illumination, both detection elements are 2 and 3 detected dark. When the lighting is green, the detection element 2 still dark and the detection element 3 but detected brightly. With blue and green lighting, the reflection behavior of the detection elements changes compared to the situation with only green lighting 2 and 3 Not.

With regard to the reflection and absorption behavior of the codes 104 , 106 and 108 it can be stated that these show the same behavior with only blue and alternatively blue and additionally green lighting. In other words, the reflection and absorption behavior of the codes changes 104 , 106 and 108 not with additional lighting with green light. The color design of the codes 104 , 106 and 108 is chosen accordingly.

According to 26th are both the three codes 104 , 106 and 108 , which are designed as data matrix codes, as well as the detection elements 2 and 3 that are above the codes 104 , 106 and 108 are arranged, each in a common viewing window 5 of the detector. The relative speed can be determined in such a way that the detector only covers the area in the viewing window 5 reads, in which the detection elements 2 and 3 are located. Alternatively, both the detection elements 2 and 3 as well as the codes 104 , 106 and 108 can be evaluated simultaneously or in quick succession in any order.

For a reliable evaluation of the brightness curve and / or the code content, it is assumed that the relative speed between the object and the detector does not change during the recording.

One advantage of the exemplary embodiment explained here is that the relative speed can be determined with high reliability. This is not possible with many other known methods. In addition, the detection elements must be colored 2 and 3 in black and green colors commonly used codes in the printing process 104 , 106 and 108 not much to be changed. All that is required is an additional printing color and a further lighting color for the second light.

A velocity vector on which the relative movement is based - without direction - and the depth of field can be viewed as a superposition of convolution matrices. Conversely, it is also possible to recalculate the corresponding convolution matrix from the image of the very well known objects and to determine the speed component from this.

With reference to the method claimed in claim 9 for determining the relative speed between an object and a detector, a reliable determination of the relative speed can also be carried out on the basis of an alternative lighting pattern. The detection elements 2 , 3 during the relative movement and for a predefinable duration Δt an image recording by the detector 1 by means of a lighting device in a predeterminable sequence and specifiable respective lighting duration alternating with light of different wavelengths 6th and 7th illuminated. There is therefore alternating lighting and no lighting with "basic lighting" and superimposed additional lighting.

Thereby the wavelengths 6th and 7th chosen such that from the detector 1 a first detection element 2 in the case of illumination with a first wavelength 6th dark and with an illumination with one of the first wavelength 6th different second wavelength 7th is also detected dark. A second detection element 3 becomes with an illumination with the first wavelength 6th likewise dark and with an illumination with the second wavelength 7th but detected brightly. The area 4th is both with an illumination with the first wavelength 6th as well as with an illumination with the second wavelength 7th bright with correspondingly low or high brightness B. detected.

The further steps with regard to image recording, detection of a brightness curve and evaluation of the brightness curve take place as in the previously described method and the associated exemplary embodiments.

In an exemplary application of this method for determining the relative speed between an object and a detector, it is used in combination with codes configured as data matrix codes, for example, which are used, for example, to determine the relative position between an object and a detector. An arrangement of codes 104 , 106 and 108 in connection with assigned detection elements 2 and 3 according to 26th can also be used as a basis for this exemplary embodiment of the method.

In this exemplary embodiment, with regard to the illumination pattern for determining the relative speed, it is important that the first wavelength 6th and the second wavelength 7th are relatively close to each other and lead to light consisting of two shades of blue or two shades of red, for example. For example, a wavelength of 600 nm can be used as the first wavelength 6th and 650 nm as the second wavelength 7th with regard to the shade of red. With regard to a shade of blue, for example, 450 nm can be used as the first wavelength 6th and 400 nm as the second wavelength 7th be used. The colors for the data matrix code can then be selected with the colors black, white, cyan and orange in such a way that they show the same reflections and absorptions for the two red and the two blue illumination colors. It is therefore irrelevant for the decoding of the data matrix codes whether one or the other color - for example with a wavelength separation of 50 nm in each case - is used for illumination. As a color for the second detection element 3 a shade of green - for example grass - can be used again, but this is due to the change of 50 nm in the wavelengths 6th and 7th responds. More precisely, it should reflect at 600 nm and 450 nm and absorb at 650 nm and 400 nm. Thus, the detection elements 2 and 3 and so that the object is illuminated, for example, the first 50% of the illumination duration with 400 nm and the second 50% of the illumination duration with 450 nm. The colors of the data matrix code then show the same reflection and absorption behavior in both time periods. A detector evaluating the code content thus detects the change from the first wavelength 6th to the second wavelength 7th no difference in terms of the reflections and absorptions of the data matrix code. The detection elements 2 and 3 above the code - green / black square - however, show a change. A large, completely black square is detected in the first 50% of the lighting time and only the smaller inner black square is detected in the second 50% of the lighting time. A comparable reflection and absorption behavior is in the two middle situations 26th regarding the detection elements 2 and 3 shown. When the object moves relative to the detector 1 shows in the recorded image a shift of the smaller square compared to the large square. Such a shift during a relative movement is shown in FIG 35 shown.

In the exemplary embodiment shown here, the first and second wavelengths lying close to one another 6th and 7th there is the advantage that a white element of a code 104 , 106 and 108 does not have to be adjusted in a special way with regard to its reflection behavior, since both wavelengths 6th and 7th with their alternating lighting lead to almost the same reflection behavior of the white elements. An absorbing or blocking portion in the white color is therefore not necessary, as may be necessary, for example, in the first exemplary embodiment, depending on the color design of the detection elements and the illuminating light.

27 shows in a schematic representation of the wavelength-dependent absorption spectra with regard to the colors orange, cyan and grass as well as the associated position of the illuminating blue tones and red tones, each having a wavelength of 400 nm and 450 nm (blue tones) and 600 nm and 650 nm (Red tones). It can be seen that the blue tones are both absorbed by orange and both reflected by cyan, but only blue 1 reflected from grass and blue 2 is absorbed by grass. Red for the reds 1 and red 2 Both shades of red are reflected by orange and absorbed by cyan, with red 1 reflected from grass and red 2 is absorbed by grass.

The 28 , 29 and 30th show in schematic representations in the upper two spectra again the in 27 Detailed description of the absorption and reflection behavior of the blue and red tones in relation to the colors orange, cyan and grass. The lower four spectra show how orange ( 28 ), Cyan ( 29 ) and grass ( 30th ) with blue lighting 1 , Blue 2 , Red 1 or red 2 behaves in terms of reflection. It can be seen that orange when illuminated with red 1 and red 2 light is detected, cyan when illuminated with blue 1 and blue 2 is detected brightly and grass when illuminated with blue 1 and red 2 bright is detected. In all other cases "dark" is detected.

31 shows in a table again the reflection and absorption behavior of orange, cyan and grass when illuminated with blue 1 , Blue 2 , Red 1 or red 2 . Here, too, it can be seen that orange when illuminated with blue 1 or blue 2 , Cyan when illuminated with red 1 or red 2 and grass when lit with blue 2 or red 1 is detected dark. With the other constellations between color and lighting, a “bright” detection takes place.

32 shows two different situations according to the above-described subdivision into parts a), b) and c), with the above situation lighting with successively the blue tones blue 1 and blue 2 takes place during half of the entire exposure time. In the illustration below, there is successive lighting with the red tones red 1 and red 2 . In both situations the colors orange, cyan, grass and black are arranged next to one another, whereby in part b) the corresponding absorption and reflection behavior when illuminated with blue 1 and blue 2 or red 1 and red 2 is shown. The associated brightness gradients are shown in parts c). With this lighting in the two in 32 In the situations shown, there is no movement of the color elements orange, cyan, grass and black.

33 shows four situations with a movement to the right and different sequences of lighting with the tones blue 1 , Blue 2 as well as red 1 and red 2 in this and in reverse order of blue 2 to blue 1 and of red 2 to red 1 . The detection elements 2 and 3 are black or grass-colored. In a corresponding manner, the different reflection and absorption behavior of the detection elements are shown in parts b) 2 and 3 and in parts c) the respective brightness curve resulting therefrom is shown. It can be seen that the brightness gradients in the two upper situations and also in the two lower situations are identical. That is, the lighting with the sequence of blue 1 to blue 2 leads to the same brightness curve as the illumination of red 2 to red 1 . Correspondingly, and in accordance with the two situations below, the lighting sequence is blue 2 to blue 1 and red 1 to red 2 always the same brightness curve.

The situations in 34 basically correspond to the respective situations in 33 , namely with regard to the lighting sequence and the color design of the detection elements 2 and 3 . However, the movement takes place in the in 34 situations shown to the left. Here, too, the same brightness curve results in the two upper situations and likewise the same brightness curve in the two lower situations. In addition, the lower two situations show accordingly 33 the same brightness curve as the two situations above 34 , although the movement in 33 to the right and in 34 goes to the left. The two situations above show the 33 the same brightness curve as the two situations below in 34 .

35 shows in six representations two differently implemented arrangements of detection elements 2 and 3 , whereby the two upper representations show the situation at a standstill, ie without movement. In the two middle situations there was a movement to the left or to the right, with the lighting being blue 1 to blue 2 or of red 2 to red 1 has been changed. The result is a final state at the end of the exposure with the detection element moved to the right or to the left 2 . In the two lower situations, a movement to the left or a movement to the right has also taken place, although the lighting sequence differs from the situations in the middle 35 are swapped. A movement of the detection element results accordingly 2 to the left or to the right in the image recorded by the detector.

With regard to further advantageous embodiments of the teaching according to the invention, to avoid repetition, reference is made to the general part of the description and to the appended claims.

Finally, it should be expressly pointed out that the exemplary embodiments described above only serve to explain the teaching claimed, but do not restrict them to these exemplary embodiments.

List of reference symbols

1

detector

2

first detection element

3

second detection element

4th

Area

5

Viewing window

6th

first wavelength

7th

second wavelength

8th

falling edge

9

rising edge

10

constant section

11

top

104

code

106

code

108

code

d

width

Δt

Duration of an image recording

t

time

x

place

B.

brightness

D.

distance

L.

Length of a detection element

M.

Focus

P

Length of the constant section

Q

Width of the tip

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 0532169 A1 [0003]
• EP 1729086 A1 [0004]

Claims (21)

Method for determining the relative speed between an object and a detector (1), wherein a relative movement between the object and the detector (1) can take place in one direction of movement, wherein the object has at least two detection elements (2, 3) which have a different reflectance spectrum relative to a predeterminable area (4) of the object and different from one another, with at least one of the detection elements (2, 3) adjoining the area (4), wherein the detection elements (2, 3) during the possible relative movement and during a predeterminable duration (Δt) of an image recording by the detector (1) by means of an illumination device with a first light with a first wavelength (6) and - during a predeterminable part of itself the resulting duration of an illumination with the first light - additionally illuminated with a second light with a second wavelength (7) different from the first wavelength (6), wherein the wavelengths (6, 7) are selected such that at least one first detection element (2) of the detector (1) is dark or light in the case of illumination with the first wavelength (6) and in the case of additional illumination with the second wavelength (7) also dark or light, at least one further second detection element (3) with an illumination with the first wavelength (6) dark or light and with additional illumination with the second wavelength (7) light or dark and the area (4) with an illumination with the first wavelength (6) as well as with additional illumination with the second wavelength (7) light or dark with correspondingly low or high brightness (B) are detected, whereby in the image recording generated by this, a brightness curve dependent on the remission spectra of the area (4) and the detection elements (2, 3) and the different wavelengths (6, 7) of the illuminations with decreasing and / or increasing brightnesses (B) in the possible Direction of movement is detected by the detector (1), and wherein based on a proportionality of a spatial width (d) of a decreasing or increasing section of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light, the relative speed is determined and / or wherein based on a proportionality of a distance between two constant sections (10) and / or a distance (D) from centers (M) of two constant sections (10) and / or a width (Q) of a tip (11) between two constant sections ( 10) of the brightness curve in relation to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light, the relative speed is determined. Procedure according to Claim 1 , characterized in that the remission spectra of the detection elements (2, 3) and the first wavelength (6) and / or the second wavelength (7) are selected to be coordinated with one another in such a way that the additional illumination of a code arranged on or on the object, in particular a data matrix code or a barcode, with the second wavelength (7) or the first wavelength (6) essentially no change from initially by illuminating the code with the first wavelength (6) or the second wavelength (7) by the code caused reflections and / or absorptions. Procedure according to Claim 1 or 2 , characterized in that one or more elements and / or one or more areas of a code arranged on or on the object, in particular a data matrix code or a barcode, have the second wavelength (7) and / or the first wavelength (6) has or have absorbent or blocking portion. Method according to one of the Claims 1 to 3 , characterized in that the time of the start and / or the duration of the illumination with the second light - are or will be predetermined - preferably by means of a control device and more preferably randomly. Method according to one of the Claims 1 to 4th , characterized in that the direction of movement is determined taking into account the shape of the brightness curve and / or the point in time of the start and / or the duration of the illumination with the second light. Method according to one of the Claims 1 to 5 , characterized in that the first light and / or the second light are or will be switched on or off with increasing and / or decreasing intensity. Method according to one of the Claims 1 to 6th , characterized in that the duration of the illumination with the first wavelength (6) is specified. Method according to one of the Claims 1 to 7th , characterized in that an image scale realized during the image recording and / or a blurring caused by an objective of the detector (1) is or is specified during the image recording. Method for determining the relative speed between an object and a detector (1), wherein a relative movement between the object and the detector (1) can take place in one direction of movement, wherein the object has at least two detection elements (2, 3) which have a different reflectance spectrum relative to a predeterminable area (4) of the object and different from one another, with at least one of the detection elements (2, 3) adjoining the area (4), wherein the detection elements (2, 3) are alternately illuminated with light of different wavelengths (6, 7) during the possible relative movement and for a specifiable duration (Δt) of an image recording by the detector (1) by means of an illumination device in a specifiable sequence and specifiable respective illumination duration , wherein the wavelengths (6, 7) are selected such that a first detection element (2) of the detector (1) is dark or light when illuminated with a first wavelength (6) and dark or light when illuminated with one of the first wavelength (6 ) different second wavelength (7) also dark or light, a second detection element (3) dark or light when illuminated with the first wavelength (6) and light or dark when illuminated with the second wavelength (7) and the area (4 ) are detected both with an illumination with the first wavelength (6) and with an illumination with the second wavelength (7) light or dark with correspondingly low or high brightness (B), whereby in the image recording generated by this, a brightness curve dependent on the remission spectra of the area (4) and the detection elements (2, 3) and the different wavelengths (6, 7) of the illuminations with decreasing and / or increasing brightnesses (B) in the possible Direction of movement is detected by the detector (1), and wherein based on a proportionality of a spatial width (d) of a decreasing or increasing section of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light, the relative speed is determined and / or wherein based on a proportionality of a distance between two constant sections (10) and / or a distance (D) from centers (M) of two constant sections (10) and / or a width (Q) of a tip (11) between two constant sections ( 10) of the brightness profile in relation to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light, the relative speed is determined. Procedure according to Claim 9 , characterized in that the remission spectra of the detection elements (2, 3) and the first wavelength (6) and / or the second wavelength (7) are selected to be coordinated with one another in such a way that a change in the illumination of the detection elements (2, 3) of light with the first wavelength (6) to light with the second wavelength (7) or vice versa, essentially no change from initially illuminating a code arranged on or on the object, in particular a data matrix code or a barcode, with the first wavelength ( 6) or the second wavelength (7) causes reflections and / or absorptions generated by the code. Procedure according to Claim 9 or 10 , characterized in that after half a duration (Δt) of the image recording, the wavelength of the illumination is changed from the first wavelength (6) to the second wavelength (7). Method according to one of the Claims 9 to 11 , characterized in that taking into account the shape of the brightness curve and the sequence of the wavelengths (6, 7) of the lighting, the direction of movement is determined. Method according to one of the Claims 1 to 12 , characterized in that a monochrome camera, preferably a camera with a pixel sensor, is used as the detector (1), the pixel sensor further preferably being designed as a CMOS sensor or CCD sensor or as a line sensor. Method according to one of the Claims 1 to 13 , characterized in that the detection elements (2, 3) are arranged on, on or in the object adjacent to one another and / or in one another. Method according to one of the Claims 1 to 14th , characterized in that the detection elements (2, 3) are arranged adjacent to one another in the direction of movement. Method according to one of the Claims 1 to 15th , characterized in that the detection elements (2, 3) have a rectangular or round contour, the detection elements (2, 3) preferably being elements of a code, in particular a data matrix code or a barcode, or next to such a code or are arranged in the object. Method according to one of the Claims 1 to 15th , characterized in that the detection elements are implemented as linear detection elements extending in the direction of movement. Method according to one of the Claims 1 to 17th , characterized in that the area (4) is implemented as a light or white or as a dark or black area (4) or background and / or that the area (4) has a high or low level of remission for at least one predeterminable spectral range and / or for at least one wavelength. Method according to one of the Claims 1 to 18th , characterized in that the duration (Δt) of the image recording is specified in such a way that the object or the detection elements (2, 3) do not move or move out of a viewing window (5) of the detector during the duration (Δt) of the image recording. Device for carrying out a method for determining the relative speed between an object and a detector (1), preferably for carrying out a method according to one of the Claims 1 to 8th and possibly one or more of the Claims 13 to 19th , wherein a relative movement between the object and the detector (1) can take place in one direction of movement, the object having at least two detection elements (2, 3) which have a different remission spectrum relative to a predeterminable area (4) of the object and different from one another , wherein at least one of the detection elements (2, 3) adjoins the area (4), wherein the detection elements (2, 3) during the possible relative movement and during a predeterminable duration (Δt) of an image recording by the detector (1) by means of an illumination device with a first light with a first wavelength (6) and - during a predeterminable part of itself the resulting duration of an illumination with the first light - can also be illuminated with a second light with a second wavelength (7) different from the first wavelength (6), the wavelengths (6, 7) being selected such that the detector ( 1) at least one first detection element (2) when illuminated with the first wavelength (6) dark or light and with additional illumination with the second wavelength (7) also dark or light, at least one further second detection element (3) when illuminated with the first wavelength (6) dark or light and with additional illumination with the second wavelength (7) light or dark and the Area (4) can be detected both with an illumination with the first wavelength (6) and with additional illumination with the second wavelength (7) light or dark with correspondingly low or high brightness (B), with one of the reflectance spectra of the area (4) and the detection elements (2, 3) and the different wavelengths (6, 7) of the illuminations dependent brightness curve with decreasing and / or increasing brightnesses (B) in the possible direction of movement by the detector (1) is, and based on a proportionality of a spatial width (d) of a decreasing or increasing section of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light, the relative speed can be determined and / or based on a proportionality of a distance between two cons tant sections (10) and / or a distance (D) from centers (M) of two constant sections (10) and / or a width (Q) of a tip (11) between two constant sections (10) of the brightness curve to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light, the relative speed can be determined. Device for carrying out a method for determining the relative speed between an object and a detector (1), preferably for carrying out a method according to one of the Claims 9 to 12 and possibly one or more of the Claims 13 to 19th , wherein a relative movement between the object and the detector (1) can take place in one direction of movement, the object having at least two detection elements (2, 3) which have a different remission spectrum relative to a predeterminable area (4) of the object and different from one another , wherein at least one of the detection elements (2, 3) adjoins the area (4), the detection elements (2, 3) during the possible relative movement and during a predeterminable duration (Δt) of an image recording by the detector (1) by means of an illumination device can be illuminated alternately with light of different wavelengths (6, 7) in a specifiable sequence and specifiable respective illumination duration, the wavelengths (6, 7) being selected in such a way that a first detection element (2) of the detector (1) when illuminated with a first wavelength (6) dark or light and with an illumination with one of the first wavelength (6) different second wavelength (7) also dark or light, a second detection element (3) with an illumination with the first wavelength (6) dark or light and with an illumination with the second wavelength (7) light or dark and the area (4) light or dark with correspondingly low or high brightness (B) can be detected both with illumination with the first wavelength (6) and with illumination with the second wavelength (7), with one of the reflectance spectra of the area in the image recording generated thereby (4) and the detection elements (2, 3) and the different wavelengths (6, 7) of the illuminations depending on the brightness curve with decreasing and / or increasing brightness (B) in the possible direction of movement of the detector (1) can be detected, and where based on a proportionality of a spatial width (d) of a decreasing or increasing section of the brightness curve to the relative speed possibility and taking into account an illumination duration of the first light and / or an illumination duration of the second light, the relative speed can be determined and / or where based on a proportionality of a distance between two constant sections (10) and / or a distance (D) from centers (M) of two constant sections (10) and / or a width (Q) of a tip (11) between two constant sections (10) of the brightness curve relative to the relative speed and taking into account an illumination duration of the first light and / or an illumination duration of the second light, the relative speed can be determined is.

Images