DE102019204795A1 - LIDAR sensor, vehicle and method for a LIDAR sensor - Google Patents

Abstract

The present invention relates to a LIDAR sensor. The LIDAR sensor comprises an irradiation element which is set up to continuously emit electromagnetic radiation at a continuously changing emission angle in relation to a reference axis into the surroundings of the LIDAR sensor. The irradiation element has no mechanically movable components. Furthermore, the LIDAR sensor comprises a photodetector which is set up to receive reflections of the electromagnetic radiation from the environment.

Description

The present invention relates to a LIDAR (light detection and ranging) sensor, a vehicle and a method for a LIDAR sensor.

Ordinary LIDAR systems use mechanically moved transmitter and receiver units. Such LIDAR systems are for example in the publications EP 2 388 615 A1 , US 2017/0269215 A1 , US 2017/0350983 A1 , US 2018/0164408 A1 or WO 2017/210418 A1 described.

In particular, in order to enable 360 ° coverage of the surroundings, the transmitting and receiving units in these LIDAR systems are always mechanically moved in both the horizontal and vertical directions. The mechanical adjustment leads to mechanical wear on the moving components. Mechanically moved LIDAR systems also require a large installation space.

It is also known to combine several LIDAR systems by means of sensor fusion for a 360 ° environment detection. This is associated with high hardware and, in particular, high software expenditure. A high computing power is required for the sensor fusion. The costs for merged LIDAR systems are correspondingly high.

Both of the above-mentioned LIDAR architectures also have the inherent disadvantage that they only resolve their environment discretely or in steps (e.g. row by row or column by column). Known LIDAR architectures therefore only allow discrete spatial resolution, but no continuous or stepless spatial resolution.

Against this background, it is an object of the present invention to provide an improved possibility for scanning surroundings by means of LIDAR.

The object according to the invention is achieved by a LIDAR sensor, a vehicle and a method for a LIDAR sensor according to the independent claims.

Further aspects and developments of the invention are described in the dependent claims, the following description and in the figures.

According to a first aspect, the invention relates to a LIDAR sensor. The LIDAR sensor comprises an irradiation element which is set up to continuously (continuously, uninterrupted) emit electromagnetic radiation at a continuously (steadily, uninterrupted) changing angle of radiation in relation to a reference axis into the surroundings of the LIDAR sensor. The electromagnetic radiation can comprise radiation components at one or more wavelengths. The electromagnetic radiation can have radiation components both in the visible and in the invisible spectrum. The irradiation element has no mechanically movable components. In other words: the irradiation element only has components that are not mechanically movable. The reference axis can be any spatial axis. For example, the reference axis can be an optical axis of the irradiation element. The reference axis can e.g. be a horizontal or a vertical axis.

Furthermore, the LIDAR sensor comprises a photodetector which is set up to receive reflections of the electromagnetic radiation from the environment. The photodetector is a radiation-sensitive (e.g. light-sensitive) element that provides an output signal depending on the incident electromagnetic radiation. For example, the photodetector can be a single radiation-sensitive sensor element (i.e. a single point sensor) or a one-dimensional or two-dimensional arrangement of radiation-sensitive sensor elements. In the one-dimensional arrangement, the radiation-sensitive sensor elements are arranged exclusively along one spatial direction, while in the two-dimensional arrangement the radiation-sensitive sensor elements are arranged along two different (e.g. orthogonal) spatial directions. A radiation-sensitive sensor element can e.g. a photodiode (English photo diode), an avalanche photo diode (APD), a one-photon avalanche diode (English single photon avalanche diode, SPAD) or an array of SPADs as silicon photoelectron multipliers (English silicon photomultiplier , SiPM).

Because the irradiation element continuously emits the electromagnetic radiation for scanning the surroundings of the LIDAR sensor and thereby continuously changes the radiation angle of the electromagnetic radiation with respect to the reference axis, the surroundings of the LIDAR sensor can be scanned continuously or steplessly. In contrast to this, known LIDAR architectures only allow discrete or stepped (eg line by line or column by column) scanning of their surroundings. The LIDAR sensor according to the invention therefore enables continuous spatial resolution. Since, in contrast to known LIDAR architectures, the irradiation element has no mechanically movable components, mechanical wear of the LIDAR sensor can also be avoided. Furthermore, due to the In the absence of mechanically movable components, a compact design is made possible.

According to some exemplary embodiments, the irradiation element is set up to emit the electromagnetic radiation into the environment in such a way that the emitted electromagnetic radiation has a cross section that partially or completely surrounds the reference axis in a plane orthogonal (and virtual or imaginary) to the reference axis. In other words: the irradiation element can enable 360 ° detection of the surroundings in relation to the reference axis. Optionally, the irradiation element can also enable only part of the surroundings to be recorded in relation to the reference axis.

In some exemplary embodiments, the emitted electromagnetic radiation in the plane orthogonal to the reference axis can, for example, have an annular cross section or a cross section in the form of one or more coradial ring segments (i.e. ring segments with identical radii). In other words: the irradiation element can radiate the electromagnetic radiation essentially in the form of a lateral surface of a truncated cone for 360 ° detection of the surroundings in relation to the reference axis. Similar to opening or closing an umbrella, the irradiation element continuously changes the angle between the lateral surface and the reference axis (which in this comparison corresponds to the cone axis of the truncated cone). If only part of the environment is to be captured, the irradiation element can emit the electromagnetic radiation essentially in the form of one or more partial areas or segments of the lateral surface of the truncated cone, the angle between the lateral surface and the reference axis again being continuously changed.

According to some exemplary embodiments, the irradiation element comprises a reflector which is rotationally symmetrical with respect to the reference axis. The reflector can have one or more reflector surfaces which have the same or different radii of curvature. Each of the reflector surfaces can have one or more areas with different radii of curvature. Furthermore, the irradiation element comprises a radiation source which is set up to generate collimated electromagnetic radiation. The collimated electromagnetic radiation thus consists of electromagnetic radiation directed in parallel. The irradiation element further comprises a telecentric lens which is arranged along the reference axis between the radiation source and the reflector. The entry and exit pupils of the telecentric lens are both at infinity, i.e. the object and image planes of the telecentric lens are both at infinity. The telecentric lens is set up to image the collimated electromagnetic radiation on the reflector with a continuously changing image scale, so that the collimated electromagnetic radiation is continuously reflected by the reflector with a continuously changing radiation angle in relation to the reference axis into the vicinity of the LIDAR sensor. In other words: the size of the image of the collimated electromagnetic radiation on the reflector based on the size of the collimated electromagnetic radiation incident in the telecentric lens is continuously changed by the telecentric lens in order to reflect the radiation of the electromagnetic radiation in the vicinity of the LIDAR sensor to achieve continuously changing radiation angle based on the reference axis.

In some exemplary embodiments, the telecentric lens comprises two focus-variable lenses which are set up to vary their focal lengths as a function of a respective control signal. The imaging scale of the telecentric lens is determined by the focal lengths of the first and the second focus-variable lenses. The telecentric lens further comprises a control circuit which is set up to control the two focus-variable lenses via respective control signals in order to continuously change the imaging scale of the telecentric lens. The two focus-variable lenses enable their respective lens curvatures and thus their focal lengths to be adjusted via the electronic control by means of the control signals. In other words: depending on the control signals, the focal planes on which the focus-variable lenses image the electromagnetic radiation incident on the objective can be set. For example, the variable focus lens can be a liquid lens. By means of the focus-variable lenses, the image scale of the telecentric lens can be set electronically by setting their focal lengths. Via a corresponding control of the two focus-variable lenses, the area of the reflector irradiated with the collimated electromagnetic radiation can thus be continuously changed in order to achieve the emission of the electromagnetic radiation in the vicinity of the LIDAR sensor with a continuously changing emission angle in relation to the reference axis.

In addition to the two focus-variable lenses, the telecentric lens can include further optical elements. For example, the objective can have one or more further lenses (e.g. diffusing and / or converging lenses) or lens groups (e.g. combinations of several diffusing and / or converging lenses) and / or diaphragms.

According to some exemplary embodiments, the radiation source comprises a first laser which is set up to generate a first radiation component of the electromagnetic radiation with a first wavelength. The first radiation component of the electromagnetic radiation is used to irradiate the surroundings for LIDAR scanning. For example, in some exemplary embodiments, the first wavelength can be greater than 780 nm. In other words: the surroundings can be scanned with infrared radiation (eg with a wavelength of 905 nm). In addition to the first radiation component, the electromagnetic radiation can optionally also have further radiation components (see below). Furthermore, the radiation source comprises a lens system which is arranged between the first laser and the telecentric objective and is set up to widen a cross section of the electromagnetic radiation in a plane orthogonal to the reference axis in order to generate the collimated electromagnetic radiation. The laser beam of the first laser (ie the first radiation component of the electromagnetic radiation) initially has a first extension in a plane perpendicular to its direction of propagation, which is enlarged, ie widened, by the lens system. The lens system can include, for example, a divergent lens (negative lens) for expanding the laser beam and a collimator in the form of a collecting lens, a condenser or a honeycomb condenser for the subsequent collimation of the expanded laser beam. The laser beam of the first laser can be widened by means of the lens system in such a way that the telecentric objective is irradiated over a large area by the widened laser beam (ie the electromagnetic radiation). In other words: the lens system expands the sharply focused and collimated laser beam of the first laser in order to generate the collimated electromagnetic radiation. The radiation source further comprises a first diaphragm element which is arranged between the lens system and the telecentric objective. The first screen element has an annular transmission area for the collimated electromagnetic radiation. The transmission area is that part of the diaphragm element that allows the electromagnetic radiation incident on the diaphragm element to be transmitted. The remaining areas of the screen element prevent the portions of the electromagnetic radiation impinging thereon from passing through (for example by absorption or reflection of the portions of the electromagnetic radiation). After passing through the first screen element, the collimated electromagnetic radiation thus has an annular cross section in a plane orthogonal to the reference axis (ie in a plane perpendicular to its direction of propagation). The ring-shaped collimated electromagnetic radiation is imaged onto the reflector by the telecentric lens with continuously changing image scale, so that the electromagnetic radiation in the form of a lateral surface of a truncated cone, the angle of which relative to the reference axis changes continuously, into the vicinity of the LIDAR sensor through the reflector is broadcast. In relation to the reference axis, the LIDAR sensor according to the invention can thus continuously detect the surroundings at 360 °.

In some exemplary embodiments, the radiation source further includes a second screen element with an adjustable transmission range for the collimated electromagnetic radiation. The second diaphragm element is arranged between the first diaphragm element and the telecentric lens and is set up to set a shape of its transmission area as a function of a further control signal. By setting the shape of the transmission area, the shape of the collimated electromagnetic radiation can thus be set in a plane perpendicular to its direction of propagation, that of a plane orthogonal to the reference axis. For example, one or more partial areas of the ring-shaped electromagnetic radiation impinging on the second screen element can be selectively masked out in order to set a desired radiation distribution of the electromagnetic radiation reflected by the reflector into the vicinity of the LIDAR sensor. After passing through the second diaphragm element, the collimated electromagnetic radiation can thus have a cross section in the form of one or more coradial ring segments in a plane orthogonal to the reference axis. The screen element can e.g. comprise a matrix of liquid crystals, each of which can be selectively switched between a transmission state in which the collimated electromagnetic radiation can penetrate the respective liquid crystal, and a blocking state in which the collimated electromagnetic radiation cannot penetrate the respective liquid crystal. A transmission range for the collimated electromagnetic radiation with essentially any shape can be set by means of a corresponding control of the individual liquid crystals. The control circuit is set up accordingly to control the second diaphragm element via the further control signal, depending on a desired radiation distribution of the electromagnetic radiation reflected by the reflector in the vicinity of the LIDAR sensor, to selectively transmit the collimated electromagnetic radiation that strikes the second diaphragm element from the first diaphragm element . The LIDAR sensor according to the invention can thus enable a continuous detection of selectively selected areas of its surroundings or its surroundings.

According to the above statements, the collimated electromagnetic radiation generated by the radiation source can therefore have an annular cross-section or a cross-section in the form of one or more coradial ring segments in a plane orthogonal to the reference axis.

In some exemplary embodiments, the radiation source further comprises a second laser which is set up to generate a second radiation component of the electromagnetic radiation with a second wavelength. The second wavelength is between 100 nm and 380 nm (i.e. in the ultraviolet spectral range). Furthermore, the radiation source comprises a first deflecting mirror which is set up to allow the first radiation component to be transmitted and to direct the second radiation component of the electromagnetic radiation along the reference axis onto the telecentric lens. The electromagnetic radiation which occurs on the telecentric lens can thus comprise several radiation components at different wavelengths. The second radiation component with the second wavelength between 100 nm and 380 nm can e.g. can be used for (selective) illumination of the area around the LIDAR sensor in order to deter wild animals. Electromagnetic radiation in the ultraviolet spectral range cannot be perceived by humans, but is perceived as a warning by wild animals. By illuminating the environment with ultraviolet radiation, wild animals can be deterred without dazzling or impairing people in the vicinity of the LIDAR sensor. Correspondingly, the LIDAR sensor according to the invention can also enable accidents with wild animals to be avoided in addition to continuous scanning of the surroundings. A wild animal can e.g. targeted with the ultraviolet radiation to deter it.

According to some exemplary embodiments, the radiation source further comprises a third laser which is set up to generate a third radiation component of the electromagnetic radiation with a third wavelength. The third wavelength is between 380 nm and 780 nm (i.e. in the spectral range that is visible to humans). Furthermore, the radiation source comprises a second deflection mirror which is set up to allow the first radiation component to be transmitted and to direct the third radiation component of the electromagnetic radiation along the reference axis onto the telecentric lens. The electromagnetic radiation which occurs on the telecentric lens can thus comprise several radiation components at different wavelengths. The third radiation component with the third wavelength between 380 nm and 780 nm can be used for (selective) illumination of the area around the LIDAR sensor, e.g. To project patterns or the like that are visible to humans into the environment. Likewise, people in the vicinity of the LIDAR sensor can be selectively irradiated with the radiation that can be perceived by humans. The radiation that can be perceived by humans can be selectively emitted into the vicinity of the LIDAR sensor via a corresponding control of the second screen element.

In some exemplary embodiments, the reflector tapers along the reference axis towards the radiation source. For example, the reflector can be designed as a paraboloid, the tip of which points in the direction of the radiation source or the telecentric lens. The reflector is also set up to direct the reflections of the electromagnetic radiation from the environment onto the photodetector. In other words: the reflector serves both as transmitting optics to emit the electromagnetic radiation into the environment and as receiving optics to direct the reflections of the electromagnetic radiation from the environment onto the photodetector. For example, the reflector can be designed as a partially transparent mirror.

According to some exemplary embodiments, the reflector has a first reflector surface and a second reflector surface, which are each rotationally symmetrical with respect to the reference axis. The first reflector surface tapers along the reference axis towards the radiation source, so that the collimated electromagnetic radiation is reflected from the first reflector surface into the surroundings of the LIDAR sensor. The first reflector surface surrounds the second reflector surface, so that the reflections of the electromagnetic radiation from the surroundings are reflected from the second reflector surface onto the photodetector. In other words: the second reflector surface is arranged within the first reflector surface. For example, the second reflector surface can have the shape of a conical jacket or a spherical cap. The first reflector surface can be designed as a paraboloid, for example, the tip of which points in the direction of the radiation source or the telecentric lens.

In some exemplary embodiments, the LIDAR sensor further comprises a temperature control element which is set up to set a temperature of at least part of the LIDAR sensor to a predetermined temperature or a temperature in a predetermined value range. For example, the temperature control element can heat or cool at least part of the device. Certain parts of the device, such as the radiation element or at least parts thereof, can be sensitive to their operating temperature. The Focus-variable lenses or the second diaphragm element of the telecentric lens are dependent on their operating temperature, for example with regard to their mechanisms of action (dynamics, sphericity of the lens, degree of absorption of the liquid crystals). However, the LIDAR sensor is operated, for example, in a vehicle at sometimes strongly changing temperatures - for example at comparatively high temperatures in summer and at comparatively low temperatures in winter. The temperature control element enables a temperature to be set at which temperature-sensitive components of the LIDAR sensor show a predetermined behavior. The reliability of the LIDAR sensor can thus be ensured by means of the temperature control element.

According to a further aspect, the invention relates to a vehicle which comprises a LIDAR sensor according to the invention. In general, a vehicle can be viewed as a device that includes one or more engine driven wheels (and optionally a powertrain system). For example, a vehicle can be a passenger car, truck, motorcycle, or tractor. For example, the vehicle can be an automated driving vehicle. The LIDAR sensor according to the invention can allow the vehicle a continuous or stepless spatial resolution of its surroundings.

In a further aspect, the present invention also relates to a method for a LIDAR sensor with an irradiation element and a photodetector. The method comprises a continuous emission of electromagnetic radiation into the surroundings of the LIDAR sensor at a continuously changing emission angle based on a reference axis by means of the irradiation element. The irradiation element has no mechanically movable components. The method further comprises receiving reflections of the electromagnetic radiation from the environment by the photodetector.

As already described above in connection with the LIDAR sensor according to the invention, the method according to the invention can also enable continuous or stepless spatial resolution. Since no mechanically moving components are used, mechanical wear and tear on the LIDAR sensor can also be avoided.

Possible more detailed configurations of the method are described above in connection with the device according to the invention.

• 1 schematisch ein Ausführungsbeispiel eines LIDAR-Sensors;
• 2 schematisch ein Ausführungsbeispiel eines telezentrischen Objektivs mit unterschiedlich eingestellten Abbildungsmaßstäben;
• 3 schematisch ein erstes Ausführungsbeispiel eines Reflektors zusammen mit einem Photodetektor;
• 4 schematisch ein zweites Ausführungsbeispiel eines Reflektors;
• 5 schematisch ein drittes Ausführungsbeispiel eines Reflektors zusammen mit einem Photodetektor; und
• 6 schematisch ein weiteres Ausführungsbeispiel eines LIDAR-Sensors.

Exemplary embodiments of the present invention are explained in more detail below with reference to the accompanying figures. Show it:

• 1 schematically an embodiment of a LIDAR sensor;
• 2 schematically, an embodiment of a telecentric lens with differently set image scales;
• 3 schematically a first embodiment of a reflector together with a photodetector;
• 4th schematically a second embodiment of a reflector;
• 5 schematically a third embodiment of a reflector together with a photodetector; and
• 6th schematically another embodiment of a LIDAR sensor.

1 shows a LIDAR sensor 100 with a radiation element 110 and a photodetector 120 . The photodetector 120 is designed as a two-dimensional arrangement of radiation-sensitive sensor elements (for example photodiodes).

Further is the optical axis OA of the radiation element 110 shown as a reference axis. The optical axis OA is an imaginary line of symmetry of the radiation element 110 passing through the centers of curvature of optical elements of the radiation element 110 (e.g. lenses) and is orthogonal to the remaining axes of symmetry of these optical elements.

The radiation element 110 includes a radiation source 130 , a telecentric lens 140 and a reflector 150 . The radiation source 130 generates collimated electromagnetic radiation 139 and radiates it onto the telecentric lens 140 .

For this purpose, the radiation source includes 130 a laser 131 , the electromagnetic radiation in the form of a laser beam 132 generated. The radiation source also includes 130 a lens system 133 , between the laser 131 and the telecentric lens 140 is arranged and set up, a cross section of the laser beam 132 in one to the reference axis OA to widen the orthogonal plane. To the laser beam 132 To expand, the lens system includes a divergent lens 134 . For the subsequent collimation of the expanded laser beam, the lens system includes 133 a collimator 135 (e.g. a condenser or a honeycomb condenser). The lens system 133 thus generates collimated electromagnetic radiation 136 .

Between the lens system 133 and the telecentric lens 140 is a first panel element 137 arranged, the one annular Transmission range 137-1 for the collimated electromagnetic radiation. Furthermore, the first screen element 137 an area that cannot be penetrated by the collimated electromagnetic radiation 137-2 on. For example, the first screen element 137 be designed as a contact reticle with a circular pattern. After passing through the first screen element 137 exhibits the collimated electromagnetic radiation 136 in one to the reference axis OA orthogonal plane (ie in a plane perpendicular to its direction of propagation) thus has an annular cross section.

Furthermore, is between the first screen element 137 and the telecentric lens 140 a second panel element 138 with an adjustable transmission range for the collimated electromagnetic radiation 136 arranged. The second screen element 138 is dependent on a control signal 163 a control circuit 160 a shape of its transmission area. A shape or a cross section of the collimated electromagnetic radiation can correspondingly 136 in one to the reference axis OA orthogonal plane (ie in a plane perpendicular to its direction of propagation).

The control circuit 160 controls the second panel element 138 via the control signal 163 accordingly, depending on a desired distribution of radiation from the reflector 150 in the vicinity of the LIDAR sensor 100 reflected electromagnetic radiation from the first screen element 137 on the second panel element 138 incident collimated electromagnetic radiation 136 selectively transmit, so that the collimated electromagnetic radiation 139 with a predetermined cross-section in one to the reference axis OA orthogonal plane through the radiation source 130 provided.

The one from the radiation source 130 generated collimated electromagnetic radiation 139 can thus in one to the reference axis OA orthogonal plane (ie in a plane perpendicular to its direction of propagation) either have a ring-shaped cross section or a cross section in the form of one or more coradial ring segments - depending on the control of the second diaphragm element 138 .

The telecentric lens 140 is along the reference axis OA between the radiation source 130 and the reflector 150 arranged. The telecentric lens 140 includes two focus variable lenses 141 and 142 that are set up depending on a respective control signal 161 or. 162 the control circuit 160 to vary their focal lengths. Between the two focus variable lenses 141 and 142 is a divergent lens 143 arranged with a fixed focal length.

The image scale of the telecentric lens 140 is by the focal lengths of the first and second variable focus lenses 141 and 142 certainly. This is in 2 exemplary for two different operating phases of the telecentric lens 140 shown. In the upper area of 2 is the first operating phase of the telecentric lens 140 while in the lower area of 2 a second operating phase of the telecentric lens 140 is shown.

During the second operating phase, the telecentric lens has a smaller imaging scale compared to the first operating phase 140 set. To do this is the refraction of the first focus variable lens 141 set to a larger value during the second operating phase compared to the first operating phase, so that the focal length of the first focus-variable lens 141 is less. In addition, the refraction of the second focus variable lens 142 set to a lower value during the second operating phase compared to the first operating phase, so that the focal length of the second focus-variable lens 142 is increased.

As from the comparison of the two operating phases of the telecentric lens 140 As can be seen, the size (here the diameter) is the one on the right from the telecentric lens 140 emitted electromagnetic radiation based on the size of the left side in the telecentric lens 140 incident collimated electromagnetic radiation during the two operating phases different. During the second operating phase, the diameter is that of the telecentric lens 140 emerging electromagnetic radiation is smaller than during the first operating phase. Via the corresponding control of the two focus-variable lenses 141 and 142 by the control circuit 160 can thus be the magnification of the telecentric lens 140 can be set variably.

The control circuit 160 controls the two focus variable lenses 141 and 142 via the control signals 161 and 162 to the magnification of the telecentric lens 140 to change continuously. In other words: the focus points or focus lines of the focus variable lenses 141 and 142 are parameterized. Correspondingly, the telecentric lens 140 the collimated electromagnetic radiation with continuously changing image scale on the reflector 150 pictured. Because the in the telecentric lens 140 incoming electromagnetic radiation has an annular cross-section or a cross-section in the form of one or more coradial Has ring segments, is through the telecentric lens 140 thus continuously collimated electromagnetic radiation with an annular cross section or a cross section in the form of one or more coradial ring segments onto the reflector 150 depicted, the radius of the ring or of the at least one ring segment changing continuously. In 1 is an example of electromagnetic radiation with an annular cross-section 144 shown.

The collimated electromagnetic radiation on constantly changing areas of the reflector will correspond 150 pictured. Because of the shape of the reflector 150 is the collimated electromagnetic radiation from the reflector 150 with continuously changing radiation angle based on the reference axis OA in the vicinity of the LIDAR sensor 100 reflected.

Is electromagnetic radiation with an annular cross-section on the reflector 150 shown, so encloses an imaginary section of the emitted electromagnetic radiation 101 with one to the reference axis OA orthogonal plane is the reference axis OA Completely. In other words: 360 ° of the environment in relation to the reference axis OA are affected by the electromagnetic radiation emitted 101 sampled as the electromagnetic radiation 101 is emitted essentially in the form of a lateral surface of a truncated cone, the angle between the lateral surface and the reference axis OA is continuously changed.

Will electromagnetic radiation 101 with a cross section in the form of one or more coradial ring segments on the reflector 150 shown, so encloses an imaginary section of the emitted electromagnetic radiation 101 with one to the reference axis OA orthogonal plane is the reference axis OA only partially. In other words: less than 360 ° of the environment in relation to the reference axis OA are affected by the electromagnetic radiation emitted 101 sampled as the electromagnetic radiation 101 is emitted essentially in the form of one or more partial areas or segments of a lateral surface of a truncated cone, the angle between the lateral surface and the reference axis OA is continuously changed.

With the different diameters on the reflector 150 projected electromagnetic radiation (e.g. infrared radiation) is effectively a travel path on a rotationally symmetrical reflector 150 provided to enable the continuously changing deflection of the electromagnetic radiation into the environment. The special shape of the solid of revolution 150 enables the electromagnetic radiation (eg a laser beam) to be reflected in a defined direction. Is the LIDAR sensor like in 1 shown arranged along a vertical spatial axis, the emitted electromagnetic radiation takes place 101 a vertical movement in the environment (similar to the movement of the tarpaulin of an umbrella when opening or closing).

1 thus shows a radiation element 110 which has no mechanically moving parts and a continuous emission of electromagnetic radiation 101 at a continuously changing angle of radiation based on the reference axis OA in the vicinity of the LIDAR sensor 100 enables.

As in 1 indicated and in 3 Shown again enlarged, the reflector 150 a first reflector surface 151 and a second reflector surface 152 on. Both the first reflector surface 151 as well as the second reflector surface 152 are rotationally symmetrical in relation to the reference axis OA . The first reflector surface 151 tapers along the reference axis OA towards the radiation source 130 or the telecentric lens 140 so that a tip of the first reflector surface 151 towards the radiation source 130 or the telecentric lens 140 shows. The first reflector surface 151 has several adjoining areas with different radius of curvature. The in 1 and 3 illustrated embodiment has the first reflector surface 151 three adjoining areas 151-1 , 151-2 and 151-3 with different radius of curvature. It should be noted, however, that this is purely exemplary and the first reflector surface 151 can also have more or fewer areas with different radii of curvature. The first reflector surface 151 can for example be designed as a partially transparent mirror surface.

The first reflector surface 151 surrounds the second reflector surface 152 . The second reflector surface 152 is formed in the form of a cone shell. As in the 1 and 3 indicated are the reflections 102 of electromagnetic radiation 101 from the surroundings of the second reflector surface 152 on the photodetector 120 reflected.

The one from the reflector 150 divergent portion of the electromagnetic radiation reflected back 144 is due to the variable focus lenses 141 and 142 of the telecentric lens 140 corrected.

As indicated above, the reflector must 150 do not have two reflector surfaces as in 1 and 3 shown. An alternative embodiment example of a reflector 450 is in 4th shown. reflector 450 differs from the reflector described above 150 in that he is only the first reflector surface 151 , ie a single reflector surface. The reflector 450 additionally has an arrangement of diffractive optical elements 153 on. Diffractive optical elements are surfaces or layers that have structures in the order of magnitude of the wavelength of the electromagnetic radiation to be directed through them. By means of appropriate structuring, desired radiation guiding functions can be implemented by means of diffraction. For example, the arrangement of diffractive optical elements 153 an array of Fresnel zone plates so as to provide an array of lenses that absorb the reflections 102 of electromagnetic radiation 101 from the environment onto the photodetector 120 (not shown in 4th ) depict. The first reflector surface 151 surrounds the arrangement of diffractive optical elements 153 . The arrangement of diffractive optical elements 153 is just like the first reflector surface 151 rotationally symmetrical in relation to the reference axis OA and tapers along the reference axis OA towards the radiation source 130 or the telecentric lens 140 . The contour of the arrangement of diffractive optical elements 153 follows the contour of the first reflector surface 151 , ie one perpendicular to the surface of the first reflector surface 151 measured distance between the arrangement of diffractive optical elements 153 and the first reflector surface 151 is for each point on the surface of the first reflector surface 151 equal.

In some exemplary embodiments of the present invention, diffractive optical elements can also be one or more of the rigid lenses of the irradiation element 110 replace. For example, one or more of the diverging lenses 134 , the collimator 135 and the divergent lens 143 can be replaced by one or more diffractive optical elements to the respective function of the divergent lens 134 , the collimator 135 or the divergent lens 143 to provide. When using diffractive optical elements instead of the rigid lenses, the irradiation element 110 be made simpler and more compact.

The second reflector surface can also be shaped differently than in the 1 and 3 shown. A corresponding third embodiment of a reflector 550 is in 5 together with a photodetector 120 shown. Compared to the reflector 150 is the second reflector surface within the first reflector surface 151 shaped differently. While the second reflector surface 152 of the reflector 150 has the shape of a cone jacket, has the second reflector surface 552 of the reflector 550 the shape of a spherical cap.

In 6th is also yet another embodiment of a LIDAR sensor 600 shown. Compared to the in 1 LIDAR sensor shown 100 includes the radiation source 130 a second laser 671 , the a second radiation component of the electromagnetic radiation in the form of a second laser beam 672 generated. For example, the one from the laser 131 generated first laser beam 132 have a wavelength in the infrared spectral range, while the second laser beam 672 can have a wavelength in the spectral range visible to humans or in the ultraviolet spectral range. Correspondingly, the second radiation component of the electromagnetic radiation can be used to display patterns and geometries in the environment that are visible to humans or to deter wild animals.

The radiation source also includes 130 a first deflection mirror 681 , the first radiation component in the form of the first laser beam 131 can be transmitted and the second radiation component of the electromagnetic radiation in the form of the second laser beam 672 along the reference axis OA on the telecentric lens 140 or the further optical elements of the radiation source 130 directs. The radiation source also includes 130 a second deflection mirror 682 holding the second laser beam 672 from the second laser 671 receives and on the first deflection mirror 681 distracts.

Analogous to the above statements for the second laser 671 A radiation component according to the present invention can comprise one or more further lasers in order to generate further radiation components at further wavelengths and to couple them into the electromagnetic radiation.

The photodetector 120 can be designed so that it is only used for reflections from the first laser 131 generated radiation components is sensitive. The photodetector can do this 120 for example have a filter which is connected upstream of the radiation-sensitive sensor elements and only radiation with wavelengths in the range of the first laser 131 generated radiation components can pass to the radiation-sensitive sensor elements. As an alternative or in addition, the radiation-sensitive sensor elements of the photodetector can also be designed in such a way that they are only suitable for radiation with wavelengths in the range of that caused by the first laser 131 generated radiation components are sensitive (eg by choosing appropriate materials or material combinations for the radiation-sensitive sensor elements).

As the foregoing has shown, the present invention enables a LIDAR sensor to be provided without mechanical wear. Since no mechanically moving components are used, a compact Design are made possible. The LIDAR sensor according to the invention can therefore be easily integrated into a vehicle. In addition, the LIDAR sensor according to the invention allows continuous spatial resolution of its surroundings. Due to the ability to capture the surroundings 360 °, the use of a single LIDAR sensor according to the invention is sufficient to completely capture the surroundings. Accordingly, costs can be avoided in comparison to known LIDAR architectures.

List of reference symbols

100

LIDAR sensor

101

emitted electromagnetic radiation

102

Reflection of the electromagnetic radiation

110

Lighting element

120

Photodetector

130

Radiation source

131

first laser

132

first laser beam

133

Lens system

134

Divergent lens

135

Collimator

136

collimated electromagnetic radiation

137

first screen element

137-1

Transmission range

137-2

Area that is not penetrable for electromagnetic radiation

138

second panel element

139

collimated electromagnetic radiation

140

telecentric lens

141

focus variable lens

142

focus variable lens

143

Divergent lens

144

collimated electromagnetic radiation

150

reflector

151

first reflector surface

151-1

Area of the first reflector surface

151-2

Area of the first reflector surface

151-3

Area of the first reflector surface

152

second reflector surface

153

Arrangement of diffractive optical elements

160

Control circuit

161

Control signal

162

Control signal

163

Control signal

450

reflector

550

reflector

552

second reflector surface

600

LIDAR sensor

671

second laser

672

second laser beam

681

first deflection mirror

682

second deflection mirror

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 2388615 A1 [0002]
• US 2017/0269215 A1 [0002]
• US 2017/0350983 A1 [0002]
• US 2018/0164408 A1 [0002]
• WO 2017/210418 A1 [0002]

Claims (15)

LIDAR sensor (100), characterized by : an irradiation element (110) which is set up to continuously emit electromagnetic radiation (101) at a continuously changing emission angle with respect to a reference axis (OA) in the vicinity of the LIDAR sensor (100) wherein the irradiation element (110) has no mechanically movable components; and a photodetector (120) which is set up to receive reflections (102) of the electromagnetic radiation from the environment. LIDAR sensor (100) Claim 1 , characterized in that the irradiation element (110) is set up to emit the electromagnetic radiation (101) into the environment in such a way that the emitted electromagnetic radiation (101) in a plane orthogonal to the reference axis (OA) partially or Has completely enclosing cross section. LIDAR sensor (100) Claim 1 or Claim 2 , characterized in that the emitted electromagnetic radiation (101) in the plane orthogonal to the reference axis (OA) has an annular cross-section or a cross-section in the form of one or more coradial ring segments. LIDAR sensor (100) according to one of the Claims 1 to 3 , characterized in that the irradiation element (110) comprises: a reflector (150) which is rotationally symmetrical with respect to the reference axis (OA); a radiation source (130) which is configured to generate collimated electromagnetic radiation (139); and a telecentric lens (140) which is arranged and set up along the reference axis (OA) between the radiation source (130) and the reflector (150), the collimated electromagnetic radiation (139) with continuously changing image scale onto the reflector (150) map, so that the collimated electromagnetic radiation (139) is continuously reflected by the reflector (150) with continuously changing radiation angle based on the reference axis (OA) in the vicinity of the LIDAR sensor (100). LIDAR sensor (100) Claim 4 , characterized in that the telecentric lens (140) comprises: two focus-variable lenses (141, 142) which are set up to vary their focal lengths as a function of a respective control signal (161, 162), the image scale of the telecentric lens (140 ) is determined by the focal lengths of the two focus variable lenses (141, 142); and a control circuit (160) which is set up to control the two focus-variable lenses (141, 142) via respective control signals (161, 162) in order to continuously change the imaging scale of the telecentric lens (140). LIDAR sensor (100) Claim 5 , characterized in that the radiation source (130) comprises: a first laser (131) which is set up to generate a first radiation component (132) of the electromagnetic radiation with a first wavelength; a lens system (133) which is arranged between the first laser (131) and the telecentric lens (140) and is set up to expand a cross section of the electromagnetic radiation in a plane orthogonal to the reference axis (OA) in order to expand the collimated electromagnetic radiation (136 ) to create; a first diaphragm element (137) which is arranged between the lens system (133) and the telecentric objective (140), the first diaphragm element (137) having an annular transmission area (137-1) for the collimated electromagnetic radiation (136). LIDAR sensor (100) Claim 6 , characterized in that the radiation source (130) further comprises: a second screen element (138) with an adjustable transmission range for the collimated electromagnetic radiation (136), the second screen element (138) between the first screen element (137) and the telecentric Objective (140) is arranged and set up to set a shape of its transmission range as a function of a further control signal (163), the control circuit (160) being set up to control the second diaphragm element (138) via the further control signal (163), depending on a desired radiation distribution of the electromagnetic radiation (101) reflected by the reflector (150) in the vicinity of the LIDAR sensor (100) to selectively transmit the collimated electromagnetic radiation (136) hitting the first diaphragm element (137) on the second diaphragm element (138) . LIDAR sensor (100) Claim 6 or Claim 7 , wherein the collimated electromagnetic radiation (139) generated by the radiation source (130) has an annular cross section or a cross section in the form of one or more coradial ring segments in a plane orthogonal to the reference axis (OA). LIDAR sensor (100) according to one of the Claims 6 to 8th , characterized in that the radiation source (130) further comprises: a second laser (671) which is set up to generate a second radiation component (672) of the electromagnetic radiation with a second wavelength, the second wavelength between 100 nm and 380 nm lies; and a first deflecting mirror (681) which is set up to allow the first radiation component (132) to transmit and to direct the second radiation component (672) along the reference axis (OA) onto the telecentric lens (140). LIDAR sensor (100) according to one of the Claims 6 to 9 , characterized in that the radiation source (130) further comprises: a third laser which is set up to generate a third radiation component of the electromagnetic radiation with a third wavelength, the third wavelength being between 380 nm and 780 nm; and a second deflecting mirror which is set up to allow the first radiation component to transmit and to direct the third radiation component along the reference axis (OA) onto the telecentric lens (140). LIDAR sensor (100) according to one of the Claims 6 to 10 , characterized in that the first wavelength is greater than 780 nm. LIDAR sensor (100) according to one of the Claims 4 to 11 , characterized in that the reflector (150) tapers along the reference axis (OA) towards the radiation source (130), the reflector (150) also being set up to direct the reflections of the electromagnetic radiation from the environment towards the photodetector (120) to steer. LIDAR sensor (100) Claim 12 , the reflector (150) having a first reflector surface (151) and a second reflector surface (152) which are each rotationally symmetrical with respect to the reference axis (OA), the first reflector surface (151) extending along the reference axis (OA) towards Radiation source (130) is tapered so that the collimated electromagnetic radiation is reflected by the first reflector surface (151) into the surroundings of the LIDAR sensor (100), and wherein the first reflector surface (151) surrounds the second reflector surface (152) so that the reflections (102) of the electromagnetic radiation from the environment are reflected from the second reflector surface (152) onto the photodetector (120). Vehicle, characterized in that the vehicle has a LIDAR sensor (100) according to one of the Claims 1 to 13 includes. Method for a LIDAR sensor (100) with an irradiation element (110) and a photodetector (120), characterized by : continuous emission of electromagnetic radiation (101) in an area surrounding the LIDAR sensor (100) at a continuously changing angle of radiation based on a reference axis (OA) by means of the irradiation element (110), wherein the irradiation element (110) has no mechanically movable components; and receiving reflections (102) of the electromagnetic radiation from the environment by the photodetector (120).

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