DE102017109905B4 - Headlights with integrated lidar - Google Patents

Abstract

Motor vehicle lighting device (100) with a headlight (40) which has a light source (4) for visible light (18), an infrared radiation source (22) and a light exit optics (10) which is illuminated by the light source (4) and the infrared radiation source (22), and with an optical output deflection element (30) which directs infrared radiation (23) emanating from the infrared radiation source (22) onto the light entry surface (26) of the light exit optics (10), characterized in that the optical output deflection element (30)a) has a reflector (42) which also reflects visible light (18) from the light source (4) for visible light, the reflector (42) having a focal point and a reflection surface which is illuminated by the light source (4) for visible light (18) and by the infrared radiation source (22), the light source (4) for visible light (18) being arranged closer to the focal point than the Infrared radiation source (22), orb) an exit lens (24), wherein the infrared radiation source (22) is arranged below the light source (4) for the visible light (18) when the motor vehicle lighting device (100) is used as intended, such that it radiates obliquely upwards through the exit lens (24) onto the light entry surface (26) of the light exit optics (10).

Description

The present invention relates to a motor vehicle lighting device according to the preamble of claim 1. Such a motor vehicle lighting device is known from US7,350,945 B2 known and comprises a headlight which has a light source for visible light, an infrared radiation source and a light exit optic which has a light entry surface illuminated by the light source and the infrared radiation source and a light exit surface, and which has an optical output deflection element which directs infrared radiation emanating from the infrared radiation source onto the light entry surface.

In the known motor vehicle lighting device, the infrared radiation source is arranged in a low beam headlight, which has a projection system with a light source for visible light, a reflector, a diaphragm and a projection lens. Visible light emanating from the light source is focused by the reflector onto an edge of the diaphragm, creating an internal light distribution limited by the diaphragm edge. This internal light distribution is projected by the projection lens into the area in front of the headlight, with the edge of the diaphragm being depicted as a light-dark boundary.

The aperture is arranged between the visible light source and the reflector on one side and the projection lens on the other side and it has two broad sides, of which a first broad side faces the visible light source and the reflector. The second of the two broad sides faces the projection lens.

The infrared radiation source is arranged between the diaphragm and the projection lens outside the low beam path shaded by the diaphragm. The infrared radiation source is arranged in such a way that infrared radiation emanating from it falls on the second broad side and is deflected from the second broad side onto a light entry surface of the projection lens facing the diaphragm. For this purpose, the second broad side has an optical distribution element (there reference number 13) illuminated by the infrared radiation source. The optical distribution element is designed to transmit incident infrared radiation in a predetermined manner into a predetermined solid angle. For this purpose, it can be arranged near a focal point of the projection lens and be designed in such a way that the predetermined solid angle generally corresponds to the solid angle defined by the focal point of the projection lens and its light entry surface. The only example of such an optical distribution element is US7,350,945 B2 a scattering agent (diffuser). To avoid eye damage from infrared radiation, the infrared radiation should be emitted into the solid angle of the visible dipped beam at which the dipped beam would dazzle an observer. The eye reacts to the glare with a closing pupil reflex, which then not only reduces the glare, but also reduces the eye damage from the infrared radiation.

A laser diode used as an infrared radiation source has an optical element that is designed to direct the infrared rays emitted by the infrared radiation source onto the optical distribution element. This optical element can be a convergent lens or a diffractive optical element, such as a hologram, that can be plugged onto the laser diode.

DE 197 31 754 A1 discloses a combination of headlights with distance sensors while simultaneously using optical and mechanical components for both systems for beam penetration, beam shaping and deflection.

EN 10 2005 049 685 A1 discloses a motor vehicle headlight module with at least two lighting units. Each lighting unit comprises at least one light-emitting diode chip. Different lighting units are provided for different lighting functions. The motor vehicle headlight module also has a common heat sink for the lighting units, to which the lighting units are thermally connected, and common current-stabilizing electronics for supplying voltage to the lighting units.

EN 10 2014 212 032 A1 discloses a method for detecting a roadway of a vehicle, with at least the following steps: generating a light signal and emitting the light signal onto an illuminated area of the roadway, receiving reflected radiation from the illuminated area and generating an image signal, evaluating the image signal. In this case, it is provided that the light signal is generated with light structures, the image signal is evaluated as a two-dimensional light pattern, wherein during the evaluation of the image signal, recognition of pattern features corresponding to the light structures in the light pattern is carried out, wherein a signal strength of the image pattern is evaluated in a spatially resolved manner and a reflective behavior of the illuminated area is concluded from this, and a road surface is concluded from the reflective behavior.

US 2014 / 0 042 325 A1 discloses an obstacle detection device comprising: a light source having both LED units for emitting visible light and an infrared light unit for emitting infrared light; and a rotating reflector configured to be rotated in one direction about a rotating shaft while reflecting the visible light and infrared light emitted from the light source. The rotating reflector is configured to, through its rotating motion: emit the visible light from each of the LED units as a radiation beam so that a first light distribution pattern is formed by scanning with the radiation beam; and emit the infrared light from the infrared light unit as a radiation beam so that a second light distribution pattern is formed by scanning with the radiation beam.

The present invention differs from this prior art by the characterizing features of claim 1.

These provide that the optical deflection element is a dichroic output beam splitter, an optical output diffraction element, a reflector that also reflects visible light from the light source for visible light, or an output lens.

These features mean that the vertically positioned aperture used in the current state of the art to deflect the infrared radiation emitted by the infrared radiation source onto the light entry surface of the light exit optics, which at the same time shades part of the low beam beam path, can be dispensed with. This increases the efficiency of the low beam, i.e. the proportion of the light emitted by the light source that ultimately illuminates the road ahead of the headlight.

The invention provides a LIDAR system (Light Detection And Ranging). LIDAR systems emit light and detect the backscattered radiation. The distance of the object from which the backscattered radiation emanates is determined based on the time it takes for the light to travel. LIDAR is used in the vehicle to detect people and objects in the vehicle's surroundings and to determine their distance.

Since LIDAR systems have to emit and receive light, they require optical windows in the vehicle. The backscattered light output is generally very small. To increase the signal strength, it is advantageous to use a detector system with a large opening angle. This requires large windows (openings) in the vehicle. Since these openings are already present in the headlight and the headlight optics have a comparatively large opening angle, it is of great practical benefit to use these already existing devices and components at the same time for a LIDAR system integrated in the vehicle.

An advantage of the invention is the use of the headlight optics not only for lighting purposes, but also as a subcomponent for an integrated LIDAR system.

Using the headlight optics to detect the LIDAR signal allows the large opening angle (or the large diameter) of the headlight optics to be used to improve the signal-to-noise ratio. In addition, the invention saves on optical components and can benefit from any existing headlight cleaning devices.

The integration into the headlight is interesting for high-performance headlights, for example. The LIDAR can be used to detect people who are in the immediate vicinity of the headlight. If the high radiation density poses a danger because the person has fallen below a minimum safety distance, the headlight output can be adjusted using the LIDAR signal.

A preferred embodiment is characterized in that the dichroic output beam splitter is arranged in the beam path of the visible light and is transparent to the visible light and reflects the infrared radiation, wherein the light source, dichroic output beam splitter and infrared radiation source are arranged (for example on the corners of a triangle) such that a main radiation direction of the infrared radiation emanating from the dichroic output beam splitter corresponds to the main radiation direction of the visible light emanating from the dichroic output beam splitter.

It is also preferred that the optical output diffraction element is arranged in the beam path of the visible light, wherein the light source, optical output diffraction element and infrared radiation source are arranged (for example on the corners of a triangle) such that a main radiation direction of the infrared radiation emanating from the optical output diffraction element corresponds to the main radiation direction of the visible light emanating from the optical output diffraction element.

A further preferred embodiment is characterized in that the reflector has a focal point and a reflection surface which is separated from the light source for visible light and from the Infrared radiation source, whereby the visible light source is located closer to the focal point than the infrared radiation source.

It is also preferred that the infrared radiation source, when the motor vehicle lighting device is used as intended, is arranged below the light source for the visible light in such a way that it radiates obliquely upwards through the output lens onto the light entry surface of the light exit optics.

It is also preferred that the motor vehicle lighting device has a headlight that has a light source for visible light, an infrared radiation detector, a light exit optics and an optical input deflection element that directs infrared radiation incident from the light exit optics onto the infrared radiation detector, wherein the optical input deflection element is an optical input diffraction element that is arranged in the beam path of the visible light emanating from the light source, wherein the light source, optical input diffraction element and infrared radiation detector are arranged on the corners of a triangle such that a main propagation direction of infrared radiation from an infrared radiation source of the lighting device that is reflected by an object present outside the headlight and incident into the headlight through the light exit optics is directed from the optical input diffraction element onto the infrared radiation detector. The optical input diffraction element is, for example, a diffraction grating.

It is further preferred that the motor vehicle lighting device has a headlight which has a light source for visible light, an infrared radiation detector, a light exit optics and an optical input deflection element which directs infrared radiation incident from the light exit optics onto the infrared radiation detector, wherein the input deflection element is a dichroic input beam splitter which is arranged in the beam path of the visible light emanating from the light source, wherein the light source, dichroic input beam splitter and infrared radiation detector are arranged (for example on the corners of a triangle) such that a main propagation direction of infrared radiation from the infrared radiation source which is reflected by an object present outside the headlight and enters the headlight through the light exit optics is directed by the dichroic input beam splitter onto the infrared radiation detector.

A further preferred embodiment is characterized by a headlight which has a light source for visible light, an infrared radiation detector, a light exit optics and a reflector which has a focal point and a reflection surface which is illuminated by the light source for visible light, wherein the light source, the reflector and the infrared radiation detector are arranged such that a main propagation direction of an infrared radiation from the infrared radiation source which is reflected by an object present outside the headlight and enters the headlight through the light exit optics is directed by the reflector onto the infrared radiation detector, wherein the light source for visible light is arranged closer to the focal point than the infrared radiation detector.

It is also preferred that the motor vehicle lighting device has a headlight which has a light source for visible light, an infrared radiation detector, a light exit optics and an optical input deflection element which directs infrared radiation incident from the light exit optics onto the infrared radiation detector, wherein the input deflection element is a waveguide which has broad sides and at least one narrow side, which is transparent to visible light and is arranged in the beam path of the visible light such that a first broad side of its broad sides is illuminated with visible light emanating from the light source, wherein the first broad side is opaque to infrared radiation originating from the infrared radiation source and wherein the infrared radiation detector is arranged on a narrow side of the waveguide which is permeable to the infrared radiation.

It is further preferred that an area of the infrared radiation detector that is sensitive to infrared radiation is covered by a bandpass filter that is permeable to the infrared radiation of the infrared radiation source and that completely or partially blocks the radiation of other types of radiation, in particular visible light, by attenuation.

Further advantages arise from the dependent claims, the description and the accompanying figures.

It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

• 1 einen bekannten Scheinwerfer;
• 2 einen Scheinwerfer eines Ausführungsbeispiels einer erfindungsgemäßen Kraftfahrzeugbeleuchtungseinrichtung;
• 3 eine alternative Ausgestaltung eines Scheinwerfers mit einem optischen Ausgangs-Beugungselement;
• 4 ein Ausführungsbeispiel, bei dem das optische Ausgangs-Umlenkelement als Reflektor verwirklicht ist;
• 5 einen Scheinwerfer, bei dem eine Infrarotstrahlungsquelle unterhalb einer Lichtquelle für sichtbares Licht angeordnet ist;
• 6 einen Scheinwerfer, der einen Infrarotstrahlungsdetektor aufweist;
• 7 einen Scheinwerfer mit einem dichroitischen Eingangs-Strahlteiler;
• 8 einen Scheinwerfer mit einem Wellenleiter als optisches Eingangs-Umlenkelement;
• 9 einen Scheinwerfer, bei dem das optische Eingangs-Umlenkelement als Reflektor verwirklicht ist;
• 10 zeigt ein Ausführungsbeispiel einer erfindungsgemäßen Kraftfahrzeugbeleuchtungseinrichtung; und
• 11 ein weiteres Ausführungsbeispiel einer erfindungsgemäßen Kraftfahrzeugbeleuchtungseinrichtung.

Embodiments of the invention are shown in the drawings and are explained in more detail in the following description. In this case, identical reference numerals in different figures designate identical or at least similar Functionally comparable elements. They show, in schematic form:

• 1 a well-known spotlight;
• 2 a headlight of an embodiment of a motor vehicle lighting device according to the invention;
• 3 an alternative embodiment of a headlight with an optical output diffraction element;
• 4 an embodiment in which the optical output deflection element is implemented as a reflector;
• 5 a headlamp in which an infrared radiation source is arranged below a visible light source;
• 6 a headlamp having an infrared radiation detector;
• 7 a headlamp with a dichroic input beam splitter;
• 8 a headlight with a waveguide as an optical input deflection element;
• 9 a headlight in which the optical input deflection element is implemented as a reflector;
• 10 shows an embodiment of a motor vehicle lighting device according to the invention; and
• 11 a further embodiment of a motor vehicle lighting device according to the invention.

In detail, the 1 a known headlight 2 which is designed to generate a low beam distribution. This headlight 2 has a light source 4 for visible light, a mirror cover 6, a reflector 8 and a light exit optic 10, which here is a projection lens 12.

A light-dark boundary of the low beam distribution is generated by this headlight 2 by forming an edge 14 of the mirror cover 6. The use of the mirror cover 6 has advantages over the use of a standing cover, as is the case with the US7,350,945 B2 is used, the advantage of better efficiency, since light striking the aperture is not shaded, but is reflected onto the light exit optics 10. The light distribution generated by the reflector 8 and located in the plane 16 is projected onto the roadway by the projection lens 12 of the light exit optics 10 when the headlight 2 is used as intended. Visible light 18 emanates from the light source 4.

2 shows a headlight 20 of an embodiment of a motor vehicle lighting device according to the invention. Such a motor vehicle lighting device has at least one headlight, but can also have several headlights.

The headlight 20 is based on the headlight 2 and, like the headlight 2, has a light source 4 for visible light 18, a mirror cover 6, a reflector 8 and a light exit optics 10, which here is also a projection lens 12.

A light-dark boundary of a low beam distribution is also generated by the headlight 20 by imaging an edge 14 of the mirror cover 6. Here too, the light distribution of the visible light generated by the reflector 8 is projected onto the road by the projection lens 12 when the headlight 20 is used as intended. This also applies to the 3 and 5 to 8 described embodiments. The 4 and 9 show headlights working without a projection lens.

In addition, the headlight 20 has an infrared radiation source 22. The infrared radiation source 22 is preferably an IR laser diode that emits infrared radiation. Optionally, an output lens 24 is arranged in the beam path of the infrared radiation 23 emanating from the infrared radiation source 22, which transforms the infrared radiation beam emanating from the infrared radiation source 22 by increasing or decreasing its opening angle. This applies to all embodiments presented in this application.

The light exit optics 10, which here is also a projection lens 12, has a light entry surface 26 illuminated by the light source 4 and the infrared radiation source 22 and a light exit surface 28.

The headlight 20 further comprises an optical output deflection element 30 which directs infrared radiation 23 emanating from the infrared radiation source 22 onto the light entry surface 26. The optical output deflection element 30 is in the case of the 2 a dichroic output beam splitter 32.

The dichroic output beam splitter 32 is arranged in the beam path of the visible light 18 and in the beam path of the infrared radiation 23, whereby the visible light 18 is incident on one of two sides of the beam splitter 32 and the infrared radiation 23 is incident on the other of the two sides of the beam splitter 32. The dichroic output beam splitter 32 is transparent to the visible light 18, reflects but the infrared radiation 23. The light source 4, the dichroic output beam splitter 32 and the infrared radiation source 22 are arranged such that a main radiation direction of the infrared radiation 23 emanating from the dichroic output beam splitter 32 corresponds to the main radiation direction of the visible light 18 emanating from the dichroic output beam splitter 32. In the embodiment shown, the visible light 18 passes through the dichroic output beam splitter 32 without changing direction. As a result, the infrared radiation 23 is coupled into the beam path of the visible light 18 of the headlight 20.

With the help of the optional output lens 24, the opening angle of the infrared radiation 23 is shaped so that the bundle of infrared radiation 23 completely illuminates the light entry surface 26 of the light exit optics 10 of the headlight 20 after reflection at the beam splitter 32. As a result, the infrared radiation 23 leaves the headlight 20 with a large bundle width that corresponds approximately to the bundle width of the visible light 18. This bundle width therefore corresponds to the bundle width of a headlight light distribution, in particular a low beam distribution or a high beam distribution. This reduces the risk of infrared radiation for people who are close to the headlight 20 (close here means a distance of less than 5m, for example). In addition, the large and expensive light exit optics 10 are used both for the visible light 18 and for the infrared radiation 23. This applies to all embodiments presented in this application. The wavelength of the infrared radiation 23 is preferably in the wavelength range between 750 nm and 1100 nm. Infrared radiation 23 from this wavelength range can be coupled into the beam path of the visible light of the headlight 20 with almost no loss using the dichroic beam splitter 32.

3 shows an alternative design of a headlight 20, in which the infrared radiation 23 of the infrared radiation source 22 is coupled into the beam path of the visible light 18 with the aid of an optical output diffraction element 34 as an optical output deflection element 30. The output diffraction element 34 is preferably a diffraction grating. Such a diffraction grating deflects the visible light 18 and the infrared radiation 23 to different degrees and can therefore also be used to combine visible light 18 and infrared radiation 23 incident from different directions. As an alternative to a separate output diffraction element 34, the output diffraction element 34 can also be implemented as a diffractive structure that is embossed on the light entry surface 26 or the light exit surface 28 of the light exit optics 10. Here too, the light exit optics are, for example, a projection lens 12. The optical output diffraction element 34 is preferably arranged in the beam path of the visible light 18 such that a main emission direction of the infrared radiation 23 emanating from the optical output diffraction element 34 corresponds to the main emission direction of the visible light emanating from the optical output diffraction element 34. In the embodiments described up to this point, the optical output deflection element 34 and the light exit optics 10 are different components from one another.

4 shows an embodiment with a headlight 40 in which the optical output deflection element is implemented as a reflector 42. The headlight 40 has a light source 4 for visible light 18 and an infrared radiation source 22. 4a shows beam paths for visible light 18, and 4b shows beam paths for infrared radiation 23. The reflector 42 is illuminated with visible light 18 and infrared radiation 23 and couples infrared radiation 23 emanating from the infrared radiation source 22 into a beam path of the visible light 18 emanating from the light source 4. A transparent cover plate 43 covers a light exit opening of a housing (not shown) of the headlight 40. A cover plate 43 forms a light exit optic 10. The reflector 42 has a focal point and a reflection surface which is illuminated by the light source 4 for visible light 18 and by the infrared radiation source 22. The infrared radiation source 22 and the light source 4 for visible light cannot both be arranged in the focal point of the reflector 42 for reasons of space. It is preferred that the light source 4 for visible light 18 is arranged closer to the focal point of the reflector 42 than the infrared radiation source 22. The reflection surface of the reflector 42 preferably has a parabolic basic shape, so that the visible light 18 of the light source 4 emanating from it is largely parallel and far-reaching. The infrared radiation 23 of the infrared radiation source 22 emanating from the reflection surface of the reflector 42 is, on the other hand, slightly convergent due to the out-of-focus arrangement of the infrared radiation source 22 and therefore tends to illuminate the close area in front of the headlight 40 with the infrared radiation 23. This is ideal for detecting people who are directly in front of the headlight 40, which often occurs in city traffic, for example. Such detection is advantageous for protecting these people from the high radiation output of high-performance headlights. In such a case, protection can be achieved, for example, by reducing the radiation output of the visible light 18.

5 shows a headlight 20 in which the infrared radiation source 22 is arranged below the light source 4 for the visible light 18 when the motor vehicle lighting device is used as intended, such that it shines diagonally upwards through the optional output lens 24 onto the light entry surface 26 of the light exit optics 10. A high beam module could also be installed at this position. One advantage of this design is that a high beam module can be replaced by an infrared emitter module without major structural changes. The optional output lens 24 transforms the infrared radiation 23 emitted by the infrared radiation source 22 such that it completely illuminates the light entry surface 26 of the light exit optics 10.

6 shows in contrast to the 2 to 5 no longer a headlight 20 or 40 having an infrared radiation source 22, but a headlight 60 having an infrared radiation detector 62. In detail, the 6 a headlight 60 which has a light source 4 for visible light 18, the infrared radiation detector 62, a light exit optics 10 and an optical input deflection element 64 which directs infrared radiation 23 incident from the light exit optics 10 onto the infrared radiation detector 62. The optical input deflection element 64 is arranged in the beam path of the visible light 18 emanating from the light source 4. The light source 4, the optical input deflection element 64 and the infrared radiation detector 62 are arranged such that a main propagation direction of an infrared radiation 23 from an infrared radiation source of the motor vehicle lighting device (of the motor vehicle) which is reflected by an object present outside the headlight 60 and incident into the headlight 60 through the light exit optics 10 is directed by the optical input deflection element 64 onto the infrared radiation detector 62. The infrared radiation source is arranged, for example, in another headlight of the motor vehicle lighting system.

6 shows a headlight 60 with the features of the known headlight 2 from 1 , whereby the 6 The headlight 60 shown additionally has the integrated infrared radiation detector 62 and the optical input deflection element 64. The infrared radiation detector 62 serves to detect infrared radiation 23 emitted and reflected back by an infrared radiation source of the motor vehicle lighting device. The optical input deflection element 64 is, for example, an optical input diffraction element 65, for example a separate diffraction grating. Alternatively, the optical input diffraction element can be a diffracting structure that is embossed on a light entry side 26 or a light exit side 28 of the light exit optics 10. The optical input diffraction element diffracts infrared radiation 23 from an infrared radiation source of the motor vehicle lighting device, which enters the headlight 60 from the outside and is reflected in front of the headlight 60, in the direction of the infrared radiation detector 62. The optical input deflection element 64 shifts the focus of the light exit optics 10 under the mirror cover 6. In order to shield the infrared radiation detector 62 against extraneous light (ie radiation/light of wavelengths other than the wavelength of the infrared radiation), it is preferably shielded by a narrow-band optical filter 68 (bandpass). The filter 68 should only let through infrared radiation 23 emitted by an infrared radiation source 22 of the motor vehicle lighting device.

Losses do occur with a diffraction grating. When used as a safety device in high-performance headlights, where the aim is to detect people a few meters away from the headlight, high efficiency (i.e. that a lot of backscattered radiation hits the detector) is only of secondary importance.

7 shows a headlight 60 which has a light source 4 for visible light 18, an infrared radiation detector 62, a light exit optics 10 and an optical input deflection element 64 which directs infrared radiation 23 incident from the light exit optics 10 onto the infrared radiation detector 62. The optical input deflection element 64 is a dichroic input beam splitter 69 which is arranged in the beam path of the visible light 18 emanating from the light source 4. The light source 4, the dichroic input beam splitter 69 and the infrared radiation detector 62 are arranged such that a main propagation direction of an infrared radiation 23 from an infrared radiation source of the motor vehicle lighting device, which is reflected by an object present outside the headlight 60 and enters the headlight 60 through the light exit optics 10, is directed from the dichroic input beam splitter 69 onto the infrared radiation detector 62. In order to shield the infrared radiation detector 62 against extraneous light (see above), it is preferably shielded by a narrow-band optical filter 68 (bandpass). 7 shows a headlight 60 without a mirror cover. Such a headlight can be used as a high beam headlight, for example. An additional mirror cover, such as the headlight 60 of the 6 the headlight 60 of the 7 can also be converted into a low beam headlight.

8 shows an embodiment with a headlight 60, which has two reflectors 8a and 8b and two light sources 4a and 4b for visible light 18, one each for low beam and high beam. In addition, the headlight 60 has an infrared radiation detector 62, a light exit optics 10 and an optical input deflection element 64, which directs infrared radiation 23 incident from the light exit optics 10 onto the infrared radiation detector 62. The input deflection element 64 is a waveguide 70 having broad sides 70.1, 70.2 and at least one narrow side 70.3, which is transparent to visible light 18. The waveguide 70 is arranged in the beam path of the visible light 18 such that a first broad side 70.1 of its broad sides 70.1, 70.2 is illuminated with visible light 18 emanating from the light source 4a, 4b. The first broad side 70.1 is opaque to infrared radiation 23 originating from an infrared radiation source of the motor vehicle lighting device. The waveguide 70 is provided, for example, on its broad side 70.1 facing the light sources 4a, 4b for visible light, with a dichroic layer 70.4 which transmits the visible light 18 of the headlight 60 and reflects the infrared radiation 23 of an infrared radiation source of the motor vehicle lighting device. The infrared radiation detector 62 is arranged on a narrow side 70.3 of the waveguide 70 which is permeable to the infrared radiation 23.

On the broad side 70.2 of the waveguide 70 facing the light exit optics 10 there is a diffraction grating 70.5 which couples a portion of the incident infrared radiation 23 into the waveguide 70. In this arrangement, reflected infrared radiation 23 from an infrared radiation source of the motor vehicle lighting device is coupled into the planar waveguide 70 and guided through the waveguide 70 to the detector 62. In this configuration, a separate bandpass filter in front of the detector 62 may be dispensed with because the waveguide 70 in conjunction with the diffraction grating 70.5 already effects filtering. The waveguide 70 has a thickness (distance between its broad sides 70.1, 70.2) of between 1mm and 10mm. The waveguide 70 therefore requires very little space in the headlight 60, so that this infrared detection system can also be integrated into a module with low beam and high beam.

9 shows an embodiment with a headlight 80, in which the optical input deflection element 64 is implemented as a reflector 42 that also reflects visible light from the light source 4 for visible light. The headlight 80 has a light source 4 for visible light and an infrared radiation detector 62. A cover plate 43 forms a light exit optics 10. Infrared radiation 23 emanating from an infrared radiation source 22 of the motor vehicle lighting device and, after reflection outside the headlight 80 via the light exit optics 10 or via the cover plate 43, entering the headlight 80, strikes the reflector 42 serving as an optical input deflection element 64 and is deflected by it onto the infrared radiation detector 62. The headlight 80 of the 9 corresponds to the headlight 40 of the 4 with the difference that the headlight 80 has an infrared radiation detector 62 (possibly with optional optical filter 68) instead of the infrared radiation source 22 of the headlight 40.

The reflector 42 has a focal point and a reflection surface which is illuminated by the light source 4 for visible light and possibly by infrared radiation 23 incident from outside. The infrared radiation detector 62 and the light source 4 for visible light cannot both be arranged in the focal point of the reflector 42 for reasons of space. It is preferred that the light source 4 for visible light is arranged closer to the focal point of the reflector 42 than the infrared radiation detector 62. The reflection surface of the reflector 42 preferably has a parabolic basic shape, so that the visible light emanating from it is largely parallel and far-reaching (see 4 ). The infrared radiation 23 incident on the reflector 42 and directed from it to the infrared radiation detector 62 is, however, slightly divergent before it hits the reflector 42 due to the out-of-focus arrangement of the infrared radiation detector 62 (ie the rays emanating from a reflection point 84 in front of the headlight diverge). The infrared radiation 23 incident on the infrared radiation detector 62 therefore comes less from a long-distance area far in front of the headlight 80 than from a close-up area closer to the headlight 80. This arrangement is again particularly suitable for detecting people in the close-up area in front of the vehicle (0-10 m distance).

10 shows an embodiment of a motor vehicle lighting device 100 according to the invention, which has a first headlight 20 or 40 and a second headlight 60 or 80. The first headlight 20, 40 is characterized in that it has an infrared radiation source. The second headlight 60, 80 is characterized in that it has an infrared radiation detector. A control unit 120 controls the light sources for visible light and infrared radiation sources of the headlights. The control unit 120 preferably also processes signals from one or more infrared radiation detectors of the headlights 60, 80.

11 shows an embodiment of a motor vehicle lighting device 100 according to the invention, in which at least one detection channel, ie at least one infrared radiation detector (in the light module 112) and at least one infrared radiation source (in the light module 114) is arranged in a headlight 110, which has at least two light modules 112, 114. These light modules are also preferably constructed as described above with reference to one of the 1 to 9 for each headlight 20 or 40 or 60 or 80 has been explained.

For both 10 , 11 applies that a control unit 120 receives signals from the respective infrared radiation detector. If it is detected in this way that a person is in the close range (for example 0 to 10 m) in front of the switched on lighting device, the power of the visible light sources of the headlights 20, 40, 60, 80 and possibly also the radiation power of the infrared radiation source(s) of the headlights 60, 80 are reduced by the control unit 120.

Claims (6)

Motor vehicle lighting device (100) with a headlight (40) which has a light source (4) for visible light (18), an infrared radiation source (22) and a light exit optics (10) which is illuminated by the light source (4) and the infrared radiation source (22), and with an optical output deflection element (30) which directs infrared radiation (23) emanating from the infrared radiation source (22) onto the light entry surface (26) of the light exit optics (10), characterized in that the optical output deflection element (30) a) has a reflector (42) which also reflects visible light (18) from the light source (4) for visible light, the reflector (42) having a focal point and a reflection surface which is illuminated by the light source (4) for visible light (18) and by the infrared radiation source (22), the light source (4) for visible light (18) being arranged closer to the focal point than the Infrared radiation source (22), or b) an exit lens (24), wherein the infrared radiation source (22) is arranged below the light source (4) for the visible light (18) when the motor vehicle lighting device (100) is used as intended, such that it radiates obliquely upwards through the exit lens (24) onto the light entry surface (26) of the light exit optics (10). Motor vehicle lighting device (100) according to Claim 1 , with a headlight (60) which has a light source (4) for visible light (18), an infrared radiation detector (62), a light exit optics (10) and an optical input deflection element (64) which directs infrared radiation (23) incident from the light exit optics (10) onto the infrared radiation detector (62), wherein the optical input deflection element (64) is an optical input diffraction element (65) which is arranged in the beam path of the visible light emanating from the light source such that a main propagation direction of infrared radiation (23) of the infrared radiation source (22) which is reflected by an object present outside the headlight (60) and incident into the headlight (60) through the light exit optics (10) is directed by the optical input diffraction element (65) onto the infrared radiation detector (62). Motor vehicle lighting device (100) according to one of the Claims 1 until 2 , with a headlight (60) which has a light source (4) for visible light (18), an infrared radiation detector (62), a light exit optics (10) and an optical input deflection element (64) which directs infrared radiation (23) incident from the light exit optics (10) onto the infrared radiation detector (62), wherein the optical input deflection element (64) is a dichroic input beam splitter (69) which is arranged in the beam path of the visible light (18) emanating from the light source (4), wherein the light source (4), dichroic input beam splitter (69) and infrared radiation detector (62) are arranged such that a main propagation direction of infrared radiation (23) of the infrared radiation source which is reflected by an object present outside the headlight (60) and incident into the headlight (60) through the light exit optics (10) is deflected by the dichroic input beam splitter (69) is directed towards the infrared radiation detector (62). Motor vehicle lighting device (100) according to one of the Claims 1 until 3 , with a headlight (60) which has a light source (4) for visible light, an infrared radiation detector (62), a light exit optics (10) and an optical input deflection element (64) which directs infrared radiation (23) incident from the light exit optics (10) onto the infrared radiation detector (62), wherein the optical input deflection element (64) is a waveguide (70) which has broad sides and at least one narrow side, which is transparent to visible light (18) and is arranged in the beam path of the visible light (18) such that a first broad side (70.1) of its broad sides is illuminated with visible light (18) emanating from the light source (4), wherein the first broad side (70.1) is opaque to infrared radiation (23) originating from the infrared radiation source and wherein the infrared radiation detector (62) is arranged at a point which is transparent to the infrared radiation (23). narrow side of the waveguide (70). Motor vehicle lighting device (100) according to one of the preceding claims, with a headlight (80) which has a light source (4) for visible light (18), an infrared radiation detector (62) and a reflector (42) which has a focal point and a reflection surface which is illuminated by the light source (4) for visible light, wherein the light source (4), reflector (42) and infrared radiation detector (62) are arranged such that a main propagation direction of an infrared radiation (23) of the infrared radiation source which is reflected by an object present outside the headlight (80) and incident on the reflector (42) is directed from the reflector (42) to the infrared radiation detector (62), wherein the light source (4) for visible light (18) is arranged closer to the focal point than the infrared radiation detector (62). Motor vehicle lighting device (100) according to one of the Claims 1 until 5 , wherein a surface of the infrared radiation detector (62) sensitive to infrared radiation (23) is covered by a bandpass filter (68) which is permeable to the infrared radiation (23) of the infrared radiation source (22) and completely or partially blocks the radiation of other types of radiation, in particular visible light, by attenuation.

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