JP6775430B2 - Lighting equipment and methods for monitoring lighting equipment - Google Patents

Description

The present invention relates to a luminaire and a method for monitoring the luminaire. In particular, the present invention relates to the monitoring of a lighting device, including a deflector that deflects a light beam radiated from a light source and oriented.

Background Technology German Patent Application Publication No. 1020110850559 (DE1020110850559A1) discloses a vehicle lighting device. The illuminator includes a light source and a light guide unit that forms a predetermined light distribution. The light guide unit here includes a deflection plane with multiple micromirrors that can be adjusted independently of each other around the swivel axis.

Laser-based optical modules are also used, for example, in automotive headlights. Moreover, laser-based scanning illumination modules are used in more and more applications. Here, for example, an oriented light beam from a laser source is deflected by one-dimensional or two-dimensional deflection to the transducer via a scanning mirror system. This transducer here converts normally monochromatic light into a wide wavelength spectrum, and the light emitted by it appears as, for example, white light as a whole. In this case, various adapted light distributions can be formed by the deflection system and proper drive control of the synchronous switching of the laser source.

German Patent Application Publication No. 1020110850559

Due to this principle, a laser output in the region of several Watts is required. High power densities occur in scanning light beams, optionally as a result of combination with relatively small beam diameters of less than 1 mm. Therefore, based on the high potential hazards of such high energy light beams, a proper safety concept is essential, some of which are regulated by legislative bodies.

Disclosure of the Invention According to the first aspect of the present invention, a lighting device having the characteristic portion of the independent claim 1 can be obtained.

According to the present invention here, a lighting device including a light source, a deflection device, a beam splitter, an image sensor, and an evaluation device can be obtained. The light source is configured to emit an oriented light beam. The deflector is configured to deflect the oriented light beam of the light source. The beam splitter is configured to split a portion of the light beam deflected by the deflector. The image sensor is configured to detect a part of the light beam separated by the beam splitter and supply an output signal corresponding to the detected light beam. The evaluation device is configured to receive the output signal supplied by the image sensor and detect the error function of the lighting device when the output signal supplied from the image sensor deviates from a predetermined target value. Has been done.

According to a further aspect of the present invention, there is a method for monitoring a lighting device having the feature portion of the independent claim 10.

According to this aspect of the present invention, there is a method for monitoring a lighting device including a deflector that deflects a light beam radiated from a light source and oriented. Here, the method includes a step of separating a part of the light beam deflected by the deflector and a step of detecting the separated part of the deflected light beam by an image sensor. The method further includes the step of detecting the error function of the illuminator when the separated and detected portion of the deflected light beam deviates from a predetermined target value.

Advantages of the Invention The present invention is based on the following considerations. That is, in a scanning illumination system, a beam splitter is used to separate a part of the scanning light beam, and the separated part of the scanning light beam is detected and evaluated by using an image sensor. That is. In particular, this image sensor can be flat, i.e., a two-dimensional image sensor. In this way, complete detection of scanning light beams is possible. In particular, it allows direct detection of errors due to incorrect deflection of the oriented light beam. In this way, it is possible to detect errors in driving control of the deflector for the oriented light beam. Moreover, false deflections of the oriented light beam due to damage to the deflector or misalignment can also be detected very easily. Finally, false deflections due to thermal deformation during operation of the luminaire can also be identified quickly and with high reliability.

After the light beam is deflected by the deflector, a portion of the light beam is split by the beam splitter of the illuminator according to the invention so that the image signal detected and subsequently evaluated by the image sensor is the illuminator. Corresponds to the light pattern output by. This makes it possible to infer the illumination pattern directly from the light pattern detected by the image sensor, without any additional costly processing steps. In this way, a particularly simple and effective monitoring of the lighting pattern output by the lighting device becomes possible.

The light source can be, for example, a laser source. In particular, for example, a laser source based on a semiconductor diode that emits a laser beam having a predetermined wavelength is possible. For example, as a light source, a laser source having blue light in a region between 400 and 500 nm, particularly in a region around 450 nm is possible. However, further any other light source is possible, especially a laser source having any other wavelength. Therefore, for example, a laser source in the infrared region or a laser source in the ultraviolet wavelength region is also possible. Furthermore, it is also possible to combine laser sources of different wavelengths. This makes it possible to supply, for example, a light beam containing a plurality of color components in the light. For example, red light (R), green light (G), and blue light (B) can be combined into one RGB light beam.

According to one embodiment, the lighting device further includes a conversion device. The converter is configured to convert the wavelength of the light beam emitted from the light source, at least in part, to at least one additional wavelength. According to this kind of conversion device in a lighting device, it is possible to convert the monochromatic light of a light source into light of a plurality of wavelengths, particularly light of an optical spectrum. In this way, for example, monochromatic blue light can be converted into light having a wider wavelength spectrum by using a conversion device, so that, for example, white light appears as a whole.

According to one embodiment, the converter is located in the beam path between the deflector and the beam splitter. In this way, the beam splitter separates the deflected and converted light and supplies it to the image sensor. Thereby, the image sensor can detect the light already converted by the conversion device in this case. In this way, the image sensor and subsequent evaluation device enable the conversion device to inspect proper optical conversion.

According to an alternative embodiment, a beam splitter is placed between the deflector and the converter. In this way, the beam splitter can split the scanning light beam before the light is converted by the converter. Thereby, the image sensor and the subsequent evaluation device detect a deflected light beam containing only one or more wavelengths of light emitted from the light source. This allows the image sensor to be particularly easily set and adjusted to one or more wavelengths of the light to be detected.

According to a further embodiment, the evaluation device is configured to evaluate the local light distribution on the image sensor and / or the light color of the light detected by the light sensor. In this case, the evaluation of the local light distribution on the image sensor makes it possible to detect an error in the drive control of the deflection device or an error in the drive control of the laser source. Moreover, evaluation of the local light distribution can detect false synchronization in some cases. By evaluating the light color of the light detected by the light sensor, that is, by specifying the wavelength or color spectrum detected by the image sensor, it becomes possible to detect an error in a converter, for example.

According to a further embodiment, the evaluation device is configured to switch off the light source when an error function is detected. In this way, a safe switch-off is performed to avoid the potential hazards that may arise if an error is detected in the luminaire.

According to a further embodiment, the image sensor is configured as a two-dimensional image sensor. In particular, the image sensor may be a digital image sensor such as a CCD or CMOS sensor. In this case, the image sensor may be implemented exclusively as an image sensor that detects light intensity with respect to one or more predetermined wavelengths or predetermined wavelength spectra, depending on the application case. Alternatively, the image sensor may be implemented as a color sensor that detects not only pure light intensity but also light color, i.e., the wavelength or wavelength spectrum of incident light.

According to a further embodiment, the lighting device includes a control device. This control device is configured to drive and control the deflection device. Further, this control device is configured to adapt the drive control of the deflection device by using the output signal supplied from the image sensor. In this way, the drive control of the deflector, or in some cases the drive control of additional components of the luminaire, can also be adapted in real time and, at the same time, compensate for possible failures or errors during operation. It will be possible. As a result, fluctuations during deflection due to, for example, temperature changes can be compensated in real time.

According to one embodiment, the beam splitter is configured to split less than 1% of the light intensity of light incident on the beam splitter. In particular, the beam splitter can be configured to split less than 0.5% or less than 0.1% of the light intensity of the light incident on the beam splitter. Moreover, it is also possible to split even smaller components of light intensity, for example 0.01% or in some cases 0.001%, with a beam splitter. In that case, the beam splitter, according to one embodiment, has one light intensity each over the entire scanning area of the illuminator, i.e., over the complete area where the deflector deflects the oriented light beam. Separate certain components. Alternatively, the deflector may separate part of the light intensity of the oriented light beam only in a predetermined partial region of the scanning region, eg, only in the marginal region or the central region of the center of the scanning region. Can be considered.

According to one embodiment, the deflector comprises a micromirror device having a microelectromechanical system. In particular, the deflector may include a micromirror device capable of deflecting one micromirror in two spatial directions using a microelectromechanical system. Alternatively, a deflector having two front-rear connected micromirror devices, each of which can deflect only one spatial direction, is also possible. Moreover, as a deflector, any additional deflector whose light distribution can be controlled by one light source is also possible. In particular, for example, a digital micro mirror device (DMD) capable of a variable light distribution having a modulated areal density is also possible.

According to a further aspect of the present invention, a headlight, particularly a headlight for an automobile provided with a lighting device according to the present invention, can be obtained. Moreover, additional lighting devices for lighting systems in the visible and invisible wavelength regions are also possible.

Further embodiments and advantages of the present invention will become apparent from the following description in connection with the accompanying drawings.

The schematic diagram of the lighting apparatus by one Embodiment. Schematic of a lighting device according to a further embodiment. The schematic diagram of the flowchart which is the basis of the method by one Embodiment of this invention.

FIG. 1 shows a schematic view of the lighting device 1 according to one embodiment. The lighting device 1 includes a light source 10, a deflection device 20, a beam splitter 40, an image sensor 50, and an evaluation device 60. Moreover, the illuminator 1 may further include a converter 30. Furthermore, multiple optical lenses or lens systems are also possible, but they are rarely illustrated for a better understanding of the present invention. Only one imaging lens 70 is shown for observation purposes. In this case, in the embodiments described below, the same or similar components are designated by the same reference numerals. Moreover, the embodiments described below are also capable of any combination of each other, as long as they are essentially consistent. It should be understood here that a wide range of supplements and modifications of the embodiments described are also included in aspects of the invention.

The light source 10 can be essentially any light source configured to emit an oriented light beam. In particular, for example, a laser source from which an oriented light beam is emitted is possible. Such a laser source can be realized using, for example, a suitable semiconductor diode. In particular, an oriented light source in which a plurality of individual light beams are combined into one common oriented light beam is also possible. In this case, the light source 10 may emit monochromatic light having a predetermined wavelength, for example. For example, it can be monochromatic light in this case, such as in the visible region, eg, between 400 and 500 nm, especially in the blue wavelength region around 450 nm. However, monochromatic light with wavelengths deviating from it, particularly in the ultraviolet or infrared wavelength region, is also possible. Moreover, the light source 10 may also emit an oriented light beam having light containing a plurality of wavelengths or light containing one wavelength spectrum. In particular, the light source 10 can include a plurality of individual light source elements, and these light beams are combined into one common light beam for one light beam in the light source 10. In that case, the individual light source elements may all emit light of the same wavelength, or may optionally also emit light of different wavelengths. If light having a plurality of different wavelengths is combined in the light source 10, it is possible to supply an oriented light beam having a plurality of different color components.

The light beam radiated and oriented from the light source 10 is in this case oriented in the direction of the deflector 20. The oriented light beam of the light source 10 enters the deflector 20 and is deflected from the deflector 20 in one or two spatial directions. For example, the deflector 20 can be a micromirror device that deflects one micromirror in two spatial directions, preferably orthogonal to each other. Moreover, a deflector 20 in which two more micromirrors each deflect in one spatial direction is also possible, so that by connecting these two micromirrors back and forth, similarly oriented light is possible. It is possible to deflect the beam in two spatial directions. These micromirrors can in this case be deflected by a so-called microelectromechanical system (MEMS) in order to deflect a particularly oriented light beam in a desired spatial direction. Corresponding microelectromechanical structures for this can be driven and controlled by an appropriate drive control circuit (not shown). Therefore, when the light beam radiated from the light source 10 and oriented is deflected as desired by the deflector 20, the deflected light beam scans a predetermined pattern. In this way, the desired deflection using the oriented light beam makes it possible to project a predetermined two-dimensional illumination pattern. The scanning light beam thus deflected by the deflector 20 may continue to be focused by the optical system 70 before the light beam is incident on the surface to be illuminated.

After the light beam is deflected by the deflector 20, a beam splitter 40 is further used to split a portion of the deflected light beam. The beam splitter 40, in this case, separates a portion of the deflected light beam over the entire scanning region of the deflected light beam. In this case, the expansion scale of the beam splitter 40 is at least as large as the scanning region of the deflected light beam. Alternatively, it is possible for the beam splitter 40 to split a portion of the deflected light only in a portion of the scanning region of the deflected light beam. In this case, for example, the beam splitter 40 may be arranged in the edge region of the scanning region. Alternatively, it is conceivable to place the beam splitter 40 only in the central region within the scanning region of the deflected light beam. In that case, the beam splitter 40 is smaller than the scanning region of the deflected light beam, especially significantly smaller.

The beam splitter 40 may be, for example, a so-called beam splitter plate. In this case, such a beam splitter plate reflects part of the light incident on the beam splitter plate, whereas the rest of the light incident on the beam splitter plate passes through the beam splitter plate. .. In this case, preferably the beam splitter 40 separates only very few components of the light intensity of the deflected light beam, so that most of the components of the deflected light beam pass through the beam splitter 40. .. For example, a beam splitter 40 can split less than 1%, especially less than 0.1%, of the light output of a deflected light beam. However, the beam splitter can also split 0.5% or 0.05% of the light output of the light incident on the beam splitter 40. Moreover, the beam splitter 40 is also capable of splitting even smaller components of the incident light output, for example up to 0.01% or 0.001%.

In this case, the light separated by the beam splitter 40 is deflected in the direction of the image sensor 50 by the beam splitter 40. The image sensor 50 can be a two-dimensional image sensor in this case. For example, the image sensor 50 may have a plurality of image detection elements arranged on a two-dimensional plane. In particular, an image sensor including a CCD sensor or a CMOS sensor is possible. However, any additional 2D image sensor is also possible. In this case, the image sensor 50 can only perform two-dimensional detection of the light intensity incident on the image sensor 50. At that time, the image sensor 50 can selectively react only to light having one predetermined wavelength or a plurality of predetermined wavelengths. For example, for this purpose, an appropriate filter may be placed in front of the image sensor 50. Moreover, it is also possible for the image sensor 50 to detect and evaluate the intensity of all incident light. However, as an alternative, the image sensor 50 can also detect not only pure light intensity but also light color, i.e. the wavelength or wavelength spectrum of incident light. For example, for this purpose, an image sensor including a plurality of sensor elements having different sensitivities for different wavelengths is possible. For example, the image sensor 50 may be a conventional image sensor, a conventional camera module, or the like. In addition, different light colors can be made selectable using appropriate color filters in front of the individual sensor elements of the image sensor 50 .

In addition, one more converter 30 may be provided between the deflector 20 and the beam splitter 40. The conversion device 30 can convert, for example, a part of the wavelengths of the light incident on the conversion device 30 into another wavelength or a wavelength spectrum. In this way, it is possible to generate light containing a plurality of wavelengths or wavelength spectra from, for example, monochromatic light of a deflected and oriented light beam. In this case, the beam splitter 40 is capable of splitting the entire spectrum of light produced by the converter 30.

The image sensor 50 further supplies an output signal corresponding to the detection light separated by the beam splitter 40. This output signal corresponds to an image projected on the image sensor by the beam splitter 40. In some cases, an optical system including one or more optical lenses may be further arranged between the beam splitter 40 and the image sensor 50. The image detected by the image sensor 50 is further detected and analyzed by the evaluation device 60. In this case, the evaluation device 60 can compare the image data of the output signal output from, for example, the image sensor 50 with a predetermined pattern. This predetermined pattern may correspond in this case to, for example, an image to be projected under proper drive control of the deflection device 20. If the image detected by the image sensor 50 and the desired target image correspond perfectly or at least substantially, the light beam oriented by the deflector 20 is properly deflected and there are no errors. However, if the image detected by the image sensor 50 deviates significantly from the target image to be acquired, the evaluation device 60 can detect an error in the lighting device 1. This error can be, for example, a drive control that includes an error in the deflection device 20. Proper deflection of the oriented light beam, for example based on heating, may not occur in the deflector 20. However, damage to the luminaire 1 or further failure can also be considered. Furthermore, it is possible that the oriented light beam is not properly deflected due to synchronization problems or the like. In this case, the evaluator 60 can deactivate the luminaire 1 to avoid the dangers that can arise, for example, due to the high light intensity light beam emitted with errors.

Alternatively, the evaluation device 60 or an additional control device can analyze the image data detected by the image sensor 50 and further identify the deviation between the image to be acquired and the actually detected image. Is. Further, in some cases, control parameters for adapting the deflection of the deflection device 20 can be calculated based on this deviation. In this way, even during the operation of the lighting device 1, active control for compensating for possible obstacles and the like is possible in real time.

Furthermore, under the color detection of the image projected on the image sensor 50, it is possible to detect a shift in the color spectrum or a local color change in some cases. The evaluation device 60 detects the color detected by the image sensor 50 of the image projected on the image sensor 50 by, for example, the beam splitter 40, and sets the color detected so as a desired color target value. It is possible to compare. If the color detected by the image sensor 50 deviates significantly from a predetermined color, an error or damage that may occur in the conversion device 30, for example, can be inferred from the color. It is also possible to arrange a corresponding color filter adjusted to a predetermined wavelength or a predetermined wavelength spectrum in front of the image sensor 50. When the wavelength or wavelength spectrum of the light incident on the color filter shifts, the components of the light transmitted or absorbed by the filter also change. This is brought about by the change in light intensity detected by the image sensor 50. Therefore, this makes it possible to infer possible error functions. If a change in wavelength or wavelength spectrum is detected, the light source 10 may be adapted accordingly to, in some cases, to match the color position or wavelength or wavelength spectrum of the light emitted by the light source 10. In particular, the color position can be adapted to compensate for the detected deviation.

Moreover, such as the degree of matching between the actual image projected by the deflected light beam and the image to be projected and / or a predetermined target image for the color spectrum detected by the image sensor. , The parameters specified by the evaluator 60 can also be provided by the evaluator for subsequent processing. In particular, such detected data can be stored in the error memory or, in some cases, can be displayed to the user on the display.

FIG. 2 shows a further embodiment of the lighting device 1. In this case, the lighting device 1 of the embodiment almost corresponds to the above-described embodiment. However, instead of the beam splitter 40 that reflects a small component of light to be separated, in this embodiment a small component of light to be separated passes through the beam splitter 40 and becomes a residual component of the deflected light beam. On the other hand, a beam splitter 40 is provided which reflects the light.

Moreover, the beam splitter 40 and the converter 30 can be combined into a common component, as is possible in this embodiment as well as in the embodiments described above.

Further, the conversion device 30 can be placed in the beam path behind the beam splitter 40, whereby the beam splitter 40 separates the light before the conversion by the conversion device 30.

Moreover, it is also possible to realize the transformation and division of the light beam within one common component. Thereby, for example, the conversion device 30 can reflect most of the converted light, and at the same time, a small component of the above-mentioned light can be transmitted through the conversion device 30. This transmitted light can then be detected and evaluated by the image sensor 50. Similarly, most of the light is transmitted through the converter 30 so that a small portion of the light can also be reflected by the converter 30. Here, the reflected light can be deflected to the image sensor 50 and can be detected and evaluated by the image sensor 50.

FIG. 3 is the basis of a method for monitoring the lighting device 1, and shows a schematic diagram of a flowchart which can be realized by, for example, the above-described embodiment. In particular, this method makes it possible to monitor the lighting device 1 provided with the deflection device 20 in which the deflection device 20 is illuminated by a light beam oriented by the light source 10. First, in step S1, a part of the light beam deflected by the deflector is separated. In step S2, a separated part of the deflected light beam is detected by the image sensor 50, and in step S3, a separated part of the deflected light beam is detected as a predetermined target value. If it deviates from, the error function of the lighting device 1 is detected.

In summary, the present invention relates to monitoring an illuminator with a scanning oriented light beam. In this case, after the scanning light beam is deflected, a part of the light intensity is separated and detected by using a two-dimensional image sensor. The image data thus detected by the image sensor is compared with the target value, and if there is a deviation, an error in the lighting device can be inferred.

Claims (10)

Lighting device (1)
A light source (10) configured to emit an oriented light beam, and
A deflector (20) configured to deflect the oriented light beam of the light source (10), and
A beam splitter (40) configured to split a portion of the light beam deflected by the deflector (20).
An image sensor (50) configured to detect a part of the light beam separated by the beam splitter (40) and supply an output signal corresponding to the detected light beam.
Evaluation device (60) and
With
The evaluation device (60) receives the output signal supplied by the image sensor (50), and the output signal supplied from the image sensor (50) deviates from a predetermined target value. In this case, the lighting device (1) is configured to detect the error function of the lighting device (1). 1. A conversion device (30) configured to convert light having the wavelength of the light beam emitted from the light source into light having at least one additional wavelength, at least in part. (1). The lighting device (1) according to claim 2, wherein the conversion device ( 30 ) is arranged between the deflection device (20) and the beam splitter (40). The lighting device (1) according to any one of claims 1 to 3, wherein the image sensor (50) includes a two-dimensional sensor surface. The evaluation device (60) is configured to evaluate the local light distribution on the image sensor (50) and / or the light color of the light detected by the image sensor (50). The lighting device (1) according to any one of 4 to 4. The evaluation device (60), when the error function is detected, the light source (10) is configured to switch off, the illumination device according to any one of claims 1 to 5 ( 1). A control device configured to drive and control the deflection device (20) and to adapt the drive control of the deflection device (20) using an output signal supplied from the image sensor (50). The lighting device (1) according to any one of claims 1 to 6, further comprising. The illumination according to any one of claims 1 to 7, wherein the beam splitter (40) is configured to split less than 1% of the light intensity of a light beam incident on the beam splitter (40). Device (1). The lighting device (1) according to any one of claims 1 to 8, wherein the deflection device (20) includes a micromirror device including a microelectromechanical system. A method for monitoring a lighting device (1) provided with a deflecting device (20) that deflects an oriented light beam radiated from a light source (10).
A step (S1) of separating a part of the light beam deflected by the deflector (20), and
In the step (S2) of detecting the separated part of the deflected light beam by the image sensor (50),
A step (S3) of detecting an error function of the lighting device (1) when the separated and detected part of the deflected light beam deviates from a predetermined target value.
A method characterized by including.

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