LiDAR sensor for optical detection of a field of view and method for scanning a field of view using a LiDAR sensor

Abstract

LIDAR sensor (700, 1100, 1300) for optical detection of a field of view (201) having • a transmitting unit with at least one emitter unit (103), • a receiving unit designed to receive secondary light (106) reflected and / or scattered by an object in the field of view (201) and to detect it by means of at least one detector unit (105); and • a rotatable deflection unit (701, 1101) which is designed to deflect emitted primary light (104) into the field of view (201) according to a two-dimensional scanning pattern and to deflect received secondary light (106) in the direction of the detector unit (105); • wherein the deflection unit (701, 1101) is designed as a pyramid-shaped deflection mirror (701, 1101); and wherein • the transmitting unit is designed such that the primary light (104) strikes a side surface (704, 1104) of the pyramidal deflecting mirror (701, 1101) parallel to a rotational axis (702, 1102) of the deflection unit (701, 1101); characterized in that • the emitter unit (103) is designed to emit primary light (104) in the form of a line (801, 1201-1, 1201-2, 1301-1, 1301-2); • wherein the receiving unit is configured such that received secondary light (106) strikes the same side surface (704, 1104) of the pyramidal deflecting mirror (701, 1101) as the emitted primary light (104), or that received secondary light (106) strikes a side surface (707) of the pyramidal deflecting mirror (701, 1101) adjacent to a side edge (706) of the side surface (704, 1104) on which the emitted primary light (104) strikes.

Description

[0001] The present invention relates to a LIDAR sensor for optical detection of a field of view and a method for scanning a field of view using a LIDAR sensor according to the preambles of the independent claims. State of the art

[0002] DE 10 2017 208 052 A1 discloses a transmitter optic for a LiDAR system for illuminating a field of view with light, comprising a linear light source for generating and emitting primary light in line form and a deflection optic which has a lens arrangement in an intermediate image plane of the deflection optic for emitting received primary light into the field of view and a deflection mirror that can be pivoted one-dimensionally about an axis for receiving primary light from the linear light source and for directing the primary light onto the lens arrangement and thereby imaging the linear light source onto the lens arrangement such that the image of the linear light source sweeps over the lens arrangement or a part thereof when the deflection mirror is pivoted.

[0003] From DE 20 2014 101 550 U1 a 3D camera is known with an image sensor for capturing three-dimensional image data from a viewing area and with a panoramic mirror optic arranged in front of the image sensor, wherein the geometric of the panoramic mirror optic does not form a body of revolution.

[0004] From DE 10 2019 130 647 A1, a light and distance measurement (LIDAR) receiver is known, comprising a first lens system and a first detector module that is optically coupled to the first lens system. The first lens system is configured to transmit a reflected light beam to a plurality of receiving areas of the first detector module, each of the plurality of receiving areas corresponding to a different set of receiving directions of the reflected light beam. The first detector module comprises a first photodetector array and a first integrated analog readout circuit (IC) coupled to the first photodetector array, wherein the first photodetector array and the first analog readout IC are each arranged in a different one of the plurality of receiving areas of the first detector module.The LIDAR receiver further comprises a second lens system adjacent to the first lens system and a second detector module that is optically coupled to the second lens system.

[0005] A device for creating images based on ultrasound pulses is known from US patent 2018 / 0168549 A1. Disclosure of the invention

[0006] The present invention relates to a LiDAR sensor for the optical detection of a field of view. The LiDAR sensor comprises a transmitter unit with at least one emitter unit configured to emit primary light in the form of a line; a receiver unit configured to receive secondary light reflected and / or scattered by an object in the field of view and to detect it by means of at least one detector unit; and a rotatably configured deflection unit configured to deflect emitted primary light into the field of view according to a two-dimensional scanning pattern and to deflect received secondary light in the direction of the detector unit.

[0007] According to the invention, the deflection unit is designed as a pyramid-shaped deflection mirror. Furthermore, the transmitting unit is designed such that the primary light strikes a side surface of the pyramid-shaped deflection mirror parallel to a rotational axis of the deflection unit.

[0008] The transmitter unit may include optical components such as lenses, filters, mirrors, and the like, in addition to the emitter unit. The emitter unit is specifically configured as a laser unit. This laser unit may be designed to emit laser light in the form of a line. Furthermore, the emitter unit may be configured to emit the primary light directly in the form of a line. In other words, the emitter unit may be configured as a line light source. Alternatively, an emitter unit configured to emit primary light in the form of a line can also be understood as an emitter unit that emits the primary light as a point-like beam. In this case, at least one optical element, such as a lens, is arranged within the emitter unit's beam path, configured to focus the point-like beam into a line.The emitter unit is arranged in the LIDAR sensor in such a way that the emitted primary light first hits the deflection unit and is deflected by it into the field of view.

[0009] The fact that the primary light strikes a side face of the pyramidal deflection mirror parallel to a rotation axis of the deflection unit can be understood to mean that the primary light is an extended beam and that a central beam of the emitted primary light strikes a side face of the pyramidal deflection mirror parallel to the rotation axis. This does not necessarily mean that the emitted line also strikes a side face of the pyramidal deflection mirror parallel to the rotation axis of the deflection unit. The precise position and orientation of the emitted line in the beam path and on the side face of the pyramidal deflection mirror can depend, for example, on the geometric arrangement of the emitter unit, a deflection mirror in the beam path, the deflection unit itself, and the rotation angle of the deflection unit.

[0010] The receiving unit may include optical components such as lenses, filters, mirrors, etc., in addition to the detector unit. The detector unit is specifically designed as a SPAD detector (single-photon avalanche diode).

[0011] The rotatable deflection unit can be designed to rotate around an axis of rotation. A pyramidal deflection mirror can be understood as a deflection unit having a flat, polygonal base and an apex, with the vertices of the polygon connected to the apex. The pyramidal deflection mirror has, in particular, triangular faces. Specifically, the faces of the pyramidal deflection mirror are reflective. The faces may have a reflective surface. The base of the pyramidal deflection mirror can be a triangle, quadrilateral, or pentagon. This allows the maximum field of view to be expanded or limited.

[0012] Due to the rotatable deflection unit, the field of view of the LiDAR sensor can be scanned. Because of the pyramid-shaped deflection mirror and the way the primary light strikes one of its faces during rotation, the two-dimensional scanning pattern is fan-shaped. The field of view of the LiDAR sensor can be scanned in a fan shape. This field of view has a first, for example, vertical, and a second, for example, horizontal, dimension. A fan-shaped scanning pattern can be configured, for example, such that the center of the field of view is illuminated by a line parallel to one dimension of the field of view, such as the vertical dimension. Towards the edges of the field of view, the illumination can be achieved with increasingly oblique lines.The lines can be tilted to the right at one edge of the field of vision and to the left at the other. In other words, a so-called windshield wiper effect can occur in the field of vision.

[0013] The LiDAR sensor further comprises, in particular, at least one evaluation unit. This evaluation unit is configured to determine the time of flight of the emitted primary light and the received secondary light. The distance between the LiDAR sensor and an object in the field of view can be determined, for example, based on the time of flight (TOF). Time-of-flight methods include pulse methods, which determine the reception time of a reflected laser pulse, and phase-modulated methods, which emit an amplitude-modulated light signal and determine the phase shift relative to the received light signal.

[0014] The advantage of the invention lies in the fact that optical crosstalk on the detector unit can be significantly reduced or even eliminated. This is particularly advantageous when the detector unit is designed as a SPAD detector with very high sensitivity. This prevents the false detection of non-existent objects in the field of view of the LiDAR sensor. The so-called false positive rate (FPR) can be significantly reduced. This can be particularly advantageous when using a LiDAR sensor in a vehicle with at least partial autonomy, as it reduces the need for unnecessary braking or evasive maneuvers. Furthermore, objects located near highly reflective objects can be detected much more reliably.In particular, objects located above and / or below a highly reflective object can be detected much more reliably due to the fan-shaped scanning pattern. This is especially advantageous because many objects in the environment have vertical edges and / or boundaries. This improves the overall performance of the LiDAR sensor. The pyramid-shaped deflecting mirror, however, remains relatively simple and inexpensive to manufacture.

[0015] In an advantageous embodiment of the invention, the pyramid-shaped deflection mirror is designed as a truncated pyramid. The advantage of this embodiment is that the installation space of the LIDAR sensor can be made smaller. This is particularly advantageous if the LIDAR sensor is to be installed in the body of a vehicle.

[0016] In a further advantageous embodiment of the invention, it is provided that the pyramid-shaped deflecting mirror is designed as a double-pyramidal deflecting mirror; and wherein the transmitting unit is designed such that a first part of the primary light strikes a first side surface of a first pyramid of the double-pyramidal deflecting mirror, and wherein a second part of the primary light strikes a second side surface of a second pyramid of the double-pyramidal deflecting mirror, adjacent to the first side surface at a base edge of the double-pyramidal deflecting mirror.

[0017] Here, the first part of the primary light strikes the first side surface parallel to the rotation axis of the deflection unit. Here, the second part of the primary light strikes the second side surface parallel to the rotation axis of the deflection unit.

[0018] Due to the double-pyramidal deflection mirror and the way in which the first and second parts of the primary light strike each of its faces during rotation, the two-dimensional scanning pattern is formed as a double-fan scanning pattern. This double-fan scanning pattern can be understood as a combination of two fan-shaped scanning patterns as described above. The illumination can be achieved with lines that become increasingly oblique from the center of the field of view to the edges. The first line can be tilted at an opposite angle to the second line. Thus, if the first line is tilted to the left, the second line can be tilted to the right, and vice versa. In other words, two opposing windscreen wiper effects can occur within the field of view.

[0019] The advantage of this design is that it enables even more uniform and complete illumination of the field of view compared to scanning using the pyramid-shaped deflection mirror described above.

[0020] In a further advantageous embodiment of the invention, the lidar sensor further comprises a beam splitter which divides primary light emitted by an emitter unit into the first part and the second part, and wherein the beam splitter is configured to divide the primary light in a division ratio x:y, wherein the division ratio is in particular between 50:50 and 90:10.

[0021] If the emitter unit is configured to emit the primary light as a point-like beam, and this point-like beam is shaped into a line by at least one optical element, the beam splitter can be located at various points in the beam path. Firstly, the beam splitter can be positioned downstream of the optical element and divide the shaped line into a first and a second line. Alternatively, the beam splitter can be positioned downstream of the emitter unit and initially divide the point-like beam into a first and a second point-like beam. The first and second point-like beams can then each be shaped into a first and a second line, respectively, by at least one optical element.

[0022] The advantage of this design is that, particularly with a 50:50 split ratio, it enables even more uniform and complete illumination of the field of view. A split ratio can advantageously reduce the power in one of the optical paths to such an extent that this optical path is even less susceptible to optical crosstalk. Furthermore, the design can be implemented cost-effectively using only one emitter unit.

[0023] In a further advantageous embodiment of the invention, the transmitter unit comprises at least two emitter units, wherein the first emitter unit is configured to emit the first part of the primary light, and wherein the second emitter unit is configured to emit the second part of the primary light. The two emitter units can, for example, emit primary light with different wavelengths. Alternatively or additionally, the two emitter units can be controlled such that they emit the first and second parts of the primary light asynchronously.

[0024] The advantage of this design is that it offers additional degrees of freedom in scanning, or rather capturing, the field of view. This allows objects within the field of view to be detected even more precisely.

[0025] According to the invention, the receiving unit is designed such that received secondary light hits the same side surface of the pyramidal deflecting mirror as the emitted primary light, or that received secondary light hits a side surface of the pyramidal deflecting mirror adjacent to a side edge of the side surface on which the emitted primary light hits.

[0026] If received secondary light strikes the same surface of the pyramidal deflecting mirror as the emitted primary light, it can be separated into transmitting and receiving beam paths, for example, by means of a beam splitter or a deflecting mirror with a hole. If, however, received secondary light does not strike the same surface of the pyramidal deflecting mirror as the emitted primary light, the separation is already spatially determined. This configuration is particularly advantageous in combination with a pyramidal deflecting mirror with a square base.

[0027] The invention further relates to a method for scanning a field of view using a LIDAR sensor, comprising the steps of: emission of primary light in the form of a line by means of at least one emitter unit of a transmitter unit of the LIDAR sensor; deflection of the emitted primary light by means of a rotatably designed deflection unit according to a two-dimensional scanning pattern into the field of view; reception of secondary light reflected and / or scattered in the field of view by an object by means of a receiver unit; deflection of the respective received secondary light by means of the deflection unit in the direction of at least one detector unit; and detection of the respective received and deflected secondary light by means of the at least one detector unit.

[0028] According to the invention, the deflection unit is designed as a pyramid-shaped deflection mirror. Furthermore, the emitted primary light strikes a side surface of the pyramid-shaped deflection mirror parallel to a rotational axis of the deflection unit.

[0029] The invention further relates to a computer program which is configured to execute the method described above.

[0030] The invention further assumes a machine-readable storage medium on which the computer program described above is stored.

[0031] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the present invention. Drawings

[0032] Exemplary embodiments of the present invention are explained in more detail below with reference to the accompanying drawings. Identical reference numerals in the figures denote identical or equivalently acting elements. The figures show: Fig. 1 Sampling pattern of a LIDAR sensor with line illumination according to the state of the art; Fig. 2 Optical crosstalk with a state-of-the-art LIDAR sensor in the case of small, highly (retro-)reflective objects; Fig. 3 Optical crosstalk in the case of a sign bridge with a state-of-the-art LIDAR sensor; Fig. 4 Optical crosstalk due to a highly reflective object with a state-of-the-art LIDAR sensor and the difficulty of detecting other nearby objects; Fig. 5 a line-illuminated field of view with a state-of-the-art LIDAR sensor and optical crosstalk due to a highly reflective object; Fig. 6 an embodiment of a LIDAR sensor with a pyramid-shaped deflection mirror; Fig. 7 scanning patterns of the LiDAR sensor from Fig. 6; Fig. 8 Optical crosstalk with a LiDAR sensor from Fig. 6 in the case of small, highly (retro-)reflective objects; Fig. 9 Optical crosstalk due to a highly reflective object with a LIDAR sensor Fig. 6 and the detection of a nearby object; Fig. 10 a first embodiment of a LIDAR sensor with a double pyramid-shaped deflection mirror; Fig. 11 scanning patterns of the LiDAR sensor from Fig. 10; Fig. 12 a second embodiment of a LIDAR sensor with a double pyramid-shaped deflection mirror; Fig. 13 scanning patterns of the LiDAR sensor from Fig. 13; Fig. 14 possibilities of the beam paths of the transmitting and receiving unit of the in the Fig. 6, Fig. 10 and Fig. 13 described LIDAR sensors; Fig. 15 Exemplary embodiment of a method for scanning a field of view using a LIDAR sensor.

[0033] Fig. Figure 1 shows an example of a scanning pattern of a state-of-the-art LiDAR sensor. This scanning pattern can be used to scan the field of view 201 shown here. The field of view 201 has a first extension 203 and a second extension 204. The first extension 203 can be a vertical extension of the field of view 201. The second extension 204 can be a horizontal extension of the field of view 201. The scanning pattern shown here can be implemented, for example, using a LiDAR sensor that emits primary light in line form into the field of view 201 via a deflecting mirror. The field of view 201 is illuminated by several lines 202. These lines 202 are emitted parallel to each other and at regular intervals.Especially when such a LiDAR sensor has a very sensitive SPAD sensor as its detector unit, problems can arise when detecting objects in the field of view, particularly if there are strongly (retro-)reflective objects in the field of view. This will be illustrated by the following. Fig. 2 to 5 explained in more detail.

[0034] Fig. Figure 2 illustrates the problem of optical crosstalk with a state-of-the-art line-illuminated LiDAR sensor in the case of small, highly (retro-)reflective objects. The upper part of the figure shows... Fig. 2. Vehicle 301, which is moving along a roadway 302 in a direction of travel 304. Vehicle 301 has a state-of-the-art LiDAR sensor with line illumination installed, by means of which a field of view in the direction of travel 304 in front of vehicle 301 can be detected. If the retroreflective road marking 303 is located on the roadway 302, the linear primary light emitted by the LiDAR sensor is reflected so strongly by the road marking 303 that this very small object is detected in a point cloud of the LiDAR sensor as a significantly larger, rod-like object. The area affected by this optical crosstalk is designated by area 305. The small retroreflective road marking 303 can therefore be mistakenly identified as a pylon 306 or a post 307.

[0035] Fig. Figure 3 illustrates the problem of optical crosstalk in the case of a sign bridge with a state-of-the-art LiDAR sensor and line illumination. As in Fig. Figure 2 shows a vehicle 301 moving along the roadway 302 in the direction of travel 304. The vehicle 301 is equipped with a state-of-the-art LIDAR sensor with line illumination, which allows it to detect a field of view in the direction of travel 304 in front of the vehicle 301. If a sign bridge 401 is located above the roadway 302, the state-of-the-art LIDAR sensor will not only detect the sign bridge 401 itself. Rather, due to optical crosstalk, the areas 305 below the sign bridge 401 will also be detected as false positives in the point cloud generated by the LIDAR sensor.

[0036] Fig. Figure 4 illustrates the problem of optical crosstalk due to a highly reflective object using a state-of-the-art line-illuminated LiDAR sensor and the difficulty of detecting other nearby objects. In the left part of the Fig. 4 A person 502 is walking under street sign 501. In the right part of the Fig. Figure 4 shows the point cloud of this situation, acquired using a state-of-the-art LiDAR sensor, with section 503 shown enlarged again. In this right-hand part of the Fig. Figure 4 shows that the highly retroreflective road sign 501 causes many measurement points in sub-area 305-1 of the entire marked area 305, but also many false-positive measurement points in area 305. The retroreflective road sign 501 can therefore also be described as a "Cross-Talk Causing Object" (CTCO). Humans 502 are very difficult to detect in sub-area 305-2 of area 305. This problem is also evident in Fig. 5 shown again.

[0037] Fig. Figure 5 shows a field of view 201 illuminated by lines 202, using a state-of-the-art LiDAR sensor with line illumination and optical crosstalk due to a highly reflective object. The field of view 201 has a vertical extent 203 and a horizontal extent 204. The lines 202 are parallel to the vertical extent 203. The road sign 501, acting as a CTCO (Transmissive Telescope Object), is a very strong reflector, resulting in optical crosstalk in area 305, and the person 502 under the road sign 501 is completely obscured by it.

[0038] To eliminate or at least significantly reduce the problem of optical crosstalk, the LIDAR sensors described below can be used.

[0039] Fig. Figure 6 shows an embodiment of a LiDAR sensor 700 with a deflection unit configured as a pyramidal deflection mirror 701. The LiDAR sensor 700 has a transmitter unit with an emitter unit 103. The emitter unit 103 is configured to emit primary light 104 in the form of a line. In this example, the LiDAR sensor 700 has a deflection mirror 705 configured to deflect the primary light 104 onto the pyramidal deflection mirror 701. The emitter unit 103 can be configured to emit the primary light 104 directly in the form of a line. Alternatively, the emitter unit can be configured to emit the primary light 104 as a point-like beam of light. In this case, the transmitter unit has, for example, optical lenses for beam shaping.These optical lenses can be arranged between the emitter unit 103 and the deflecting mirror 705 and / or between the deflecting mirror 705 and the pyramidal deflecting mirror 701. For simplicity, the primary light is in . Fig. 6, however, as a simple beam in Fig. Figure 6 shows the pyramid-shaped deflecting mirror 701, which is designed to deflect the primary light 104 into the field of view of the LIDAR sensor 700 according to a two-dimensional scanning pattern. The primary light 104 exits the LIDAR sensor 700 through a cover glass 102.

[0040] The pyramidal deflection mirror 701 is rotatable. The pyramidal deflection mirror 701 can rotate about the axis of rotation 702. In the example shown here, the pyramidal deflection mirror 701 has a square base 703. The corners of the square base 703 are connected to a point of the pyramidal deflection mirror 701. The pyramidal deflection mirror 701 has triangular side faces. The pyramidal deflection mirror 701 is designed to deflect emitted primary light 104 into the field of view of the LIDAR sensor 700 according to a two-dimensional scanning pattern and to deflect received secondary light towards the detector unit. The transmitter unit is designed such that the primary light 104 strikes a side face 704 of the pyramidal deflection mirror 701 parallel to an axis of rotation 702 of the pyramidal deflection mirror 701.

[0041] The LIDAR sensor 700 also includes a receiver unit (not shown here) configured to receive secondary light reflected and / or scattered by an object within its field of view and to detect it by means of at least one detector unit. The receiver unit can be configured such that the received secondary light strikes the same side surface 704 of the pyramidal deflecting mirror 701 as the emitted primary light 104. Alternatively, the receiver unit can be configured such that the received secondary light strikes a side surface 707 of the pyramidal deflecting mirror 701 adjacent to a side edge 706 of the side surface 704 upon which the primary light strikes. The pyramidal deflecting mirror 101 is configured to deflect the received secondary light in the direction of the detector unit.

[0042] Fig. Figure 7 shows a scanning pattern of the LIDAR sensor 700. Fig. 6. The two-dimensional scanning pattern is designed as a fan-shaped scanning pattern. The field of view 201 of the LIDAR sensor 700 also has a first, for example vertical, extension 203 and a second, for example horizontal, extension 204. In the center of the field of view 201, the field of view 201 is illuminated by a line 801 that is parallel to extension 203. Towards the edges of the field of view 201, marked here by the double arrow 802, the illuminating lines become increasingly oblique. Towards the left edge of the field of view 201, the lines are increasingly tilted to the right. Towards the right edge of the field of view 201, the lines are increasingly tilted to the left. Fig. 8 and Fig. Section 9 below explains the effect of such a fan-shaped scanning pattern, or the so-called windshield wiper effect, on optical crosstalk.

[0043] Fig. Figure 8 shows the effect achieved by means of the in Fig. 6 described LIDAR sensor and its in Fig. The scanning pattern described in section 7 can be used to generate optical crosstalk in the case of small, highly (retro-)reflective objects. Also in Fig. Figure 8 shows retroreflective road markings 303, a pylon 306, and a post 307 on a roadway 302. The entire scanning pattern of the LIDAR sensor 700 is not shown; only the diagonal lines 901 are shown as an example. The areas affected by optical crosstalk in this example are marked by the rectangles 902. It is evident that, due to the fan-shaped scanning pattern, more optical crosstalk is generated at a pylon 306 than at a road marking 303. Consequently, more false-positive measurement points are generated at the pylon 306 than at the road marking 303. Because of this difference, a road marking 303 can be distinguished much more easily from a pylon 306. A vehicle can recognize the road marking 303 as a small, drivable object. Unnecessary braking or evasive maneuvers can be avoided.

[0044] Fig. Figure 9 shows the effect achieved by means of the in Fig. 6 described LIDAR sensor and its in Fig. The scanning pattern described in section 7 can be used to detect optical crosstalk in the case of a highly reflective object and to identify a nearby object. Fig. 9 is similar to the Fig. 5, except that this time the field of view 201, in which the road sign 501 and the person 502 are located, is illuminated by means of a fan-shaped scanning pattern. The emitted, oblique lines 901 are shown, as well as the area 902, which is affected by optical crosstalk. The highly retroreflective road sign 501 is illuminated obliquely, so that the optical crosstalk is also detected obliquely by the detector unit of the LIDAR sensor 700. Due to the fan-shaped scanning pattern, the person 502 is virtually unaffected by the optical crosstalk. The person 502 can therefore be reliably detected.

[0045] The in Fig. The scanning pattern described in section 7 results in the field of view 201 not being illuminated evenly and completely everywhere. To improve this, the LIDAR sensor can be further modified in the manner described in the Fig. 10 and Fig. As shown in 11, it can be adjusted.

[0046] Fig. Figure 10 shows a first embodiment of a LIDAR sensor 1100 with a double-pyramidal deflection mirror 1101. In other words, the double-pyramidal deflection mirror 1101 is constructed from a first pyramid 1105-1 and a second pyramid 1105-5, which are connected to each other via the base 1103. The double-pyramidal deflection mirror 1101 is designed to rotate about the axis of rotation 1102. In this example, the transmitter unit has two emitter units 103-1 and 103-2. The two emitter units 103-1 and 103-2 can, for example, emit primary light of different wavelengths. The two emitter units 103-1 and 103-2 can, for example, emit primary light synchronously with each other. In the example shown here, the first emitter unit 103-1 is configured to emit a first part of the primary light 104-1. The LIDAR sensor 1100, in the example shown here, has a first deflecting mirror 705-1.The first part of the primary light 104-1 is deflected by the first deflecting mirror 705-1 such that it strikes a first side surface 1104-1 of the first pyramid 1105-1 of the double-pyramidal deflecting mirror 1101. In the example shown here, the second emitter unit 103-2 is configured to emit a second part of the primary light 104-2. The LIDAR sensor 1100 has a second deflecting mirror 705-2 in the example shown here. The second part of the primary light 104-2 is deflected by the second deflecting mirror 705-2 such that it strikes a second side surface 1104-2 of the second pyramid 1105-2 of the double-pyramidal deflecting mirror 1101. The second side surface 1104-2 borders the first side surface 1104-1 of the double pyramidal deflection mirror 1101 at a base edge 1103 of the double pyramidal deflection mirror 1101.

[0047] Fig. Figure 11 shows the scanning pattern of the LIDAR sensor 1100. Fig. 10. A field of view 201 with a first extension 203 and a second extension 204 is again discernible. The scanning pattern of the LIDAR sensor is designed here as a double-fan-shaped scanning pattern. It is a combination of a first fan-shaped scanning pattern 1201-1, caused by the first part of the primary light 104-1, and a second fan-shaped scanning pattern 1201-2, caused by the second part of the primary light 104-2. It can be seen that the lines of the first scanning pattern 1201-1 are at an opposite angle compared to the lines of the second scanning pattern 1201-2. The emitted lines of the first scanning pattern 1201-1 can, for example, have a different wavelength than the lines of the second scanning pattern 1201-2.

[0048] Fig. Figure 12 shows a second embodiment of a LIDAR sensor 1300 with a double-pyramidal deflection mirror 1101. Just as with the LIDAR sensor 1100, the transmitting unit of the LIDAR sensor 1300 is also configured such that a first part of the primary light 104-1 strikes a first side surface 1104-1 of a first pyramid 1105-1 of the double-pyramidal deflection mirror 1101, and that a second part of the primary light 104-2 strikes a second side surface 1104-2 of a second pyramid 1105-2 of the double-pyramidal deflection mirror 1111. The differences from the LIDAR sensor 1100 will now be discussed. The LIDAR sensor 1300 has a beam splitter 1301 which divides the primary light 104 emitted by the emitter unit 103 into the first part 104-1 and the second part 104-2. The beam splitter 1301 is configured to divide the primary light 104 in a predetermined division ratio x:y.The division ratio can be, for example, between 50:50 and 90:10. Furthermore, the LIDAR sensor 1300 has another deflecting mirror 1302 in the beam path of the second part of the primary light 104-2.

[0049] Fig. Figure 13 shows the scanning pattern of the LIDAR sensor 1300. Fig. 12. A field of view 201 with a first extension 203 and a second extension 204 is again discernible. The scanning pattern of the LIDAR sensor 1300 is also designed here as a double-fan-shaped scanning pattern. It is a combination of a first fan-shaped scanning pattern 1201-1, caused by the first part of the primary light 104-1, and a second fan-shaped scanning pattern 1301-2, caused by the second part of the primary light 104-2. It can also be seen that the lines of the first scanning pattern 1201-1 are at an opposite angle compared to the lines of the second scanning pattern 1201-2. The emitted lines of the first scanning pattern 1201-1 may, for example, have a different intensity than the lines of the second scanning pattern 1201-2.

[0050] Fig. Figure 14 shows possible beam paths of the transmitting and receiving units of the in the Fig. 6, Fig. 10 and Fig. 13 described LIDAR sensors. Both in the left and right part of the Fig. Figure 14 shows a top view of a corresponding LiDAR sensor. The LiDAR sensor components described above are arranged in a housing 101, which includes the cover glass 102. The pyramid-shaped deflection mirror 701, 1101, which is rotatable about the rotation axis 702, 1102, is shown only schematically here. A possible rotational movement of the deflection mirror 701, 1101 is indicated by arrow 109. In the left part of the Fig. Figure 14 shows an embodiment of a LIDAR sensor in which the emitted primary light 104 strikes the deflecting mirror via the same side surface as the received secondary light 106. In the right part of the Fig. Figure 14 shows an embodiment of a LIDAR sensor in which emitted primary light 104 hits a side surface of the deflection mirror 701, 1101 and in which received secondary light 106 hits an adjacent side surface of the deflection mirror 701, 1101.

[0051] Fig. Figure 15 shows an embodiment of a method 1500 for scanning a field of view using a LiDAR sensor. The method 1500 starts in step 1501. In step 1502, primary light in the form of a line is emitted by means of at least one emitter unit of a transmitter unit of the LiDAR sensor.

[0052] In step 1503, emitted primary light is deflected into the field of view by means of a rotatable deflection unit according to a two-dimensional scanning pattern. In step 1504, secondary light reflected and / or scattered by an object in the field of view is received by means of a receiver unit. In step 1505, the received secondary light is deflected by the deflection unit towards at least one detector unit. In step 1506, the received and deflected secondary light is detected by means of the at least one detector unit. Here, the deflection unit is designed as a pyramidal deflection mirror; and the emitted primary light strikes a side face of the pyramidal deflection mirror parallel to an axis of rotation of the deflection unit. The process 1500 ends in step 1508.

Claims

[1] LIDAR sensor (700, 1100, 1300) for optical detection of a field of view (201) • a transmitting unit with at least one emitter unit (103), • a receiving unit designed to receive secondary light (106) reflected and / or scattered by an object in the field of view (201) and to detect it by means of at least one detector unit (105); and • a rotatable deflection unit (701, 1101) which is designed to deflect emitted primary light (104) into the field of view (201) according to a two-dimensional scanning pattern and to deflect received secondary light (106) in the direction of the detector unit (105); • wherein the deflection unit (701, 1101) is designed as a pyramid-shaped deflection mirror (701, 1101); and wherein • the transmitting unit is designed such that the primary light (104) strikes a side surface (704, 1104) of the pyramidal deflecting mirror (701, 1101) parallel to a rotation axis (702, 1102) of the deflection unit (701, 1101); characterized by , that • the emitter unit (103) is designed to emit primary light (104) in the form of a line (801, 1201-1, 1201-2, 1301-1, 1301-2); • wherein the receiving unit is configured such that received secondary light (106) strikes the same side surface (704, 1104) of the pyramidal deflecting mirror (701, 1101) as the emitted primary light (104), or that received secondary light (106) strikes a side surface (707) of the pyramidal deflecting mirror (701, 1101) adjacent to a side edge (706) of the side surface (704, 1104) on which the emitted primary light (104) strikes. [2] LIDAR sensor (700, 1100, 1300) according to claim 1, wherein the pyramidal deflection mirror (701, 1101) is designed as a truncated pyramid. [3] LIDAR sensor (1100, 1300) according to claim 1 or 2, wherein the pyramidal deflection mirror is configured as a double pyramidal deflection mirror (1101); and wherein the transmitting unit is configured such that a first part of the primary light (104-1) strikes a first side surface (1104-1) of a first pyramid (1105-1) of the double pyramidal deflection mirror (1101), and wherein a second part of the primary light (104-2) strikes a second side surface (1104-2) of a second pyramid (1105-2) of the double pyramidal deflection mirror (1101), adjacent at a base edge (1103) of the double pyramidal deflection mirror (1101) to the first side surface (1104-1). [4] Lidar sensor (1300) according to claim 3, wherein the lidar sensor (1300) further comprises a beam splitter (1301) which divides primary light (104) emitted by an emitter unit (103) into the first part (104-1) and the second part (104-2), and wherein the beam splitter (1301) is configured to divide the primary light (104) in a division ratio x:y, wherein the division ratio is in particular between 50:50 and 90:

10. [5] LIDAR sensor (1100) according to claim 3, wherein the transmitting unit has at least two emitter units (103-1, 103-2), wherein the first emitter unit (103-1) is configured to emit the first part of the primary light (104-1), and wherein the second emitter unit (103-2) is configured to emit the second part of the primary light (104-2). [6] Method (1500) for scanning a field of view using a LIDAR sensor comprising the steps • Emission (1502) of primary light by means of at least one emitter unit of a transmitter unit of the LIDAR sensor; • Deflection (1503) of the emitted primary light by means of a rotatable deflection unit according to a two-dimensional scanning pattern into the field of view; • Receiving (1504) secondary light reflected and / or scattered in the field of view by an object by means of a receiving unit and; • Deflection (1505) of the received secondary light by means of the deflection unit in the direction of at least one detector unit; and • Detecting (1506) the received and deflected secondary light by means of at least one detector unit; • wherein the deflection unit is designed as a pyramid-shaped deflection mirror; and • wherein the primary light strikes a side surface of the pyramidal deflection mirror parallel to a rotation axis of the deflection unit; characterized by , that • the primary light is emitted in the form of a line; and • the receiving unit is designed such that received secondary light hits the same side surface of the pyramidal deflecting mirror as the emitted primary light, or that received secondary light hits a side surface of the pyramidal deflecting mirror adjacent to a side edge of the side surface on which the emitted primary light hits. [7] Computer program configured to perform the method according to claim 6. [8] Machine-readable storage medium on which the computer program according to claim 7 is stored.

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