Optical receiving sensor, optical detection system and method for operating an optical receiving sensor

Abstract

The invention relates to an optical receiving device (10) having an optical receiving sensor (12) and a reading device (14), wherein the receiving sensor (12) has a plurality of receiving pixels (16), each of which is designed to convert an optical signal (L) into an electrical receiving signal (18), the receiving pixels (16) are arranged in at least two regions (22), and the respective receiving pixels (16) within each region (22) are contiguous and are electrically connected to one another. The receiving pixels (16) can be activated in groups, and the reading device (14) activates the respective receiving pixels (16) by reading the respective electrical receiving signal (18), each group (20) of activated receiving pixels (16) having receiving pixels (16) which consist of at least two different regions (22). The invention further relates to an optical detection system (24), to a vehicle (30) having an optical detection system (24), and to a method for operating an optical receiving sensor (12).

Description

[0001] OPTICAL RECEIVING SENSOR, OPTICAL DETECTION SYSTEM AND METHOD FOR OPERATING AN OPTICAL RECEIVING SENSOR

[0002] Technical area

[0003] The application relates to an optical receiving sensor, an optical detection system, a vehicle with an optical detection system and a method for operating an optical receiving sensor.

[0004] background

[0005] Modern vehicles (cars, vans, trucks, motorcycles, etc.) are equipped with a multitude of sensor systems whose data is used to inform drivers and / or provide them to driver assistance systems. These sensor systems record the vehicle's surroundings and other road users. Based on the recorded data, a model of the vehicle's environment can be created, and changes in this environment can be responded to.

[0006] Sensor systems are constantly being developed for various functions, e.g., as systems for detecting environmental information in the near and far range of vehicles, such as passenger cars or commercial vehicles. Detection systems can also be used for driver assistance systems, especially assistance systems for autonomous or semi-autonomous vehicle control. They can be used, in particular, to detect obstacles and / or other road users in the front, rear, or blind spot area of ​​a vehicle. Detection systems can be based on various sensor principles, such as radar, ultrasound, and optics.

[0007] In optical detection systems, an important optical sensor principle for environmental detection, e.g. of vehicles, is Lidar technology (Lidar, English: Light Detection and Ranging). A Lidar system has an optical transmitter and an optical receiver. The transmitter can emit an optical signal in the form of light, which can be continuous or pulsed. The optical signal can also be modulated. In a Lidar system, light in the form of laser beams in the ultraviolet, visible, or infrared range can be used. The receiver can receive the light after reflection at a reflection point in the vicinity of the Lidar system. The received optical signal can be evaluated using the transmitted optical signal, e.g. using a time-of-flight method, and the spatial position and distance of the reflection point can be determined. The reflection can, for example,on objects in the environment. The evaluation can be performed in a computing unit of the lidar system. Reflection or reflected light is understood here to mean any light that is returned and should, in particular, also include light that is returned by scattering or absorption / emission.

[0008] An optical receiving sensor of an optical detection system can have multiple receiving elements, called pixels. A pixel of the optical receiving sensor generates an electrical signal in response to receiving an optical signal. The pixels can be configured to receive light from different solid angles.

[0009] A lidar system is an example of an active optical sensor system that emits and receives light. Passive optical sensor systems detect data based on ambient or background light. Cameras are examples of passive optical sensor systems.

[0010] DE102019212615A1 describes a detector for a lidar device with parallax compensation. The detection position of beams on the detector depends on the distance from an object in the scanning area at which the generated beams are reflected or backscattered. To compensate for the displacement, the detector pixels can be activated using selectable patterns.

[0011] Overview

[0012] An optical receiving device comprises an optical receiving sensor and a readout device. The receiving sensor comprises a plurality of receiving pixels, each configured to convert an optical signal into an electrical receiving signal. The receiving pixels are arranged in at least two regions, wherein the receiving pixels within a respective region are contiguous and have an electrical connection to one another. The receiving pixels can be activated in groups, wherein the readout device activates the respective receiving pixels by reading out the respective electrical receiving signal, wherein the respective groups of activated receiving pixels comprise receiving pixels from at least two different regions.

[0013] The receiving pixels of the optical receiving sensor contain light-sensitive components that capture light and convert it into an electrical received signal, which can be read out by the readout device and made available for further processing. The light-sensitive components can be photodiodes, charge-coupled devices (CCDs), CMOS sensors, photomultiplier tubes, SPADs, or similar devices.

[0014] Optical signals received by the optical receiving device are often concentrated on a subset of receiving pixels of the optical receiving sensor. The receiving pixels can be activated in groups, whereby the group of activated receiving pixels can form a pattern on the optical receiving sensor. The group of activated receiving pixels is characterized by the fact that the receiving pixels belonging to the group are activated simultaneously, i.e., are read out simultaneously by the readout device.

[0015] The receiving pixels of the optical receiving sensor are divided into regions. The receiving pixels within a respective region are interconnected and electrically connected to one another. The electrical connection can be provided between the receiving pixels, for example, for charge transport when the receiving pixels are read out by the readout device. The electrical connection can, in particular, comprise wiring and / or another physically provided connection. The shape of the region can depend on the arrangement of the receiving pixels on the receiving sensor. The receiving pixels belonging to the group of simultaneously read out receiving pixels are selected such that they belong to at least two different regions of receiving pixels. This also means that at least two of the receiving pixels that are activated simultaneously have no electrical connection to one another.The pattern formed by the simultaneously activatable receiving pixels of a group on the receiving sensor therefore differs from the shape of the areas.

[0016] In one embodiment of the optical receiving device, when a receiving pixel is saturated, electrical charge is transferred via the electrical connection to at least one neighboring receiving pixel within the area. Such saturation can occur, for example, when the amount of light received with the optical signal exceeds the absorption capacity of the corresponding receiving pixel. This pixel then enters saturation, i.e. it reaches its maximum absorption capacity. Such a large amount of light can occur, for example, when reflected off a highly reflective or retroreflective object in the environment. The electrical charge, which corresponds to the excess amount of light that cannot be absorbed by the corresponding receiving pixel, is then transferred via the electrical connection to neighboring receiving pixels in the area.This process can continue across multiple receiving pixels, each of which reaches saturation due to the amount of light received and / or the charge received from neighboring receiving pixels. This effect is also known as blooming.

[0017] The charge transfer due to saturation continues via the electrical connection of the receiving pixels within the respective area. The resulting overexposure can then take on the shape of the area.

[0018] If the group of activated receive pixels is specifically selected so that receive pixels outside the area are also activated, i.e. read out, it can be achieved that receive pixels that are not affected by glare are also read out. This can improve the overall reception quality. In one embodiment of the optical receiving device, the areas are disjoint. They therefore do not overlap. A respective receive pixel belongs to exactly one area. At the same time, it is preferably provided that each receive pixel of the receive sensor belongs to exactly one area. The receive pixels of the receive sensor are preferably divided into areas such that each of the receive pixels belongs to exactly one area, wherein each area is contiguous.

[0019] In the case of receiving pixels arranged in rows and columns on the receiving sensor, the shape of the region can correspond, for example, to a row or a column. In one embodiment of the optical receiving device, a respective region has, in particular, a column of receiving pixels. The column results from the orientation of the receiving sensor during operation relative to the earth's surface. If the receiving device is operated in a vehicle, for example, the column extends in a direction transverse to the earth's surface and transverse to the direction of movement of the vehicle. The row extends in a direction longitudinal to the earth's surface and transverse to the direction of movement of the vehicle.

[0020] In embodiments of the optical receiving device, the respective group of activated receiving pixels has exactly one receiving pixel per row. The pattern of the group can thus be distributed across the receiving sensor such that the receiving pixels of exactly one column are activated per row. The respective group of activated receiving pixels can therefore have as many receiving pixels as the region in a direction longitudinal to the shape of the region. In a direction transverse to the shape of the region, the group can also have as many receiving pixels as the region.

[0021] In embodiments of the optical receiving device, the respective group of activated receiving pixels in certain rows, in particular in rows located in the central region of the receiving sensor, has those receiving pixels of the row for which the highest intensity of the optical signal is expected. In regions that have the form of columns of receiving pixels, those receiving pixels in the middle of the column are therefore activated for which the greatest intensity of the optical signal is expected. When the receiving device is operated in the vehicle, this is the region in which, for example, the detection of relevant objects, e.g., other road users, is expected. In this region, high accuracy is to be achieved by activating receiving pixels with a high expected intensity.

[0022] During operation in a vehicle, nearby objects are expected or the ground is imaged for lines below the center. These objects or the ground are both closer to the receive sensor than objects imaged in the center of the receive sensor. Due to the shift in the receive signal on the receive sensor for closer objects, e.g. due to a parallax effect, receive pixels for which the shifted receive signal is expected can be activated. The group of receive pixels can therefore have a pattern in the lower area that replicates the shift in the received optical signal in the near field. Here, too, those receive pixels for which the highest intensity is expected are activated.

[0023] When operating the receiver in the vehicle, fewer relevant objects are expected for lines above the center than in the center or lower area. The area of ​​the surroundings imaged above the center refers to higher areas above the traffic. Here, the group of activated receiver pixels can be selected so that the full intensity is not expected. Given the monitored area above the traffic, sufficient relevant information can still be extracted from this adjusted group. In addition, receiver pixels that may be overexposed can be avoided during readout.

[0024] In embodiments of the optical receiving device, at least one receiving pixel is configured as a superpixel, which has multiple individual pixels. When a superpixel is activated, the individual pixels of the superpixel are read out together. Preferably, several or all receiving pixels of the receiving sensor are configured as superpixels. The superpixels can each have the same number of individual pixels or a different number of individual pixels.

[0025] In embodiments of the optical receiving device, at least one receiving pixel has at least one SPAD. A SPAD (single photon avalanche diode) is a highly sensitive light sensor capable of detecting individual photons. This type of detector utilizes the avalanche breakdown mechanism in a semiconductor material to generate a measurable electrical charge in response to the reception of a single photon. This enables SPADs to detect a very small amount of light.

[0026] At the same time, the described receiving device is particularly advantageous in conjunction with receiving sensors that have SPADs, since SPADs can easily saturate due to their high optical sensitivity. The described receiving device can advantageously counteract this sensitivity with regard to saturation. This is particularly the case when the optical receiving device is used in active optical detection systems, where saturation can occur due to the emitted optical signal during operation, especially in the presence of highly reflective objects in the environment.

[0027] In embodiments, the receiving pixels of the optical receiving sensor are formed as respective superpixels, each having a plurality of SPADs.

[0028] An optical detection system for a vehicle comprises the described optical receiving device. The optical detection system further comprises an optical transmitting device configured to transmit the optical signal. The optical detection system may, in particular, comprise a lidar system or be designed as a lidar system. The described receiving device can be advantageously used in active optical detection systems, such as lidar systems, where saturation effects of the receiving pixels can occur during operation due to the transmitted optical signal, particularly in the presence of highly reflective objects in the environment.

[0029] In embodiments of the optical detection system, in certain rows, particularly in rows located in the lower or upper region of the optical receiving sensor, the affiliation of the receiving pixels to the respective group of activated receiving pixels depends on the distance of a reflection point of the optical signal from the optical detection system. In particular, this allows for compensation of parallax shifts in the lower region. In the upper region, it can be taken into account that the objects are located at a greater altitude above the Earth's surface and may be less relevant for ground vehicles.

[0030] A vehicle may have the described optical detection system. The environmental data acquired by the detection system can be further processed in the vehicle, for example, for the purposes of autonomous or semi-autonomous driving.

[0031] The receiving sensor has a plurality of receiving pixels, each configured to convert an optical signal into an electrical receiving signal. The receiving pixels are arranged in at least two regions, with the receiving pixels within a region being contiguous and having an electrical connection to one another. A method for operating such an optical receiving sensor comprises:

[0032] Activating the receiving pixels in groups, wherein the respective receiving pixels are activated by reading out the respective electrical receiving signal, wherein the respective groups of activated receiving pixels comprise receiving pixels from at least two different areas.

[0033] The optical receiving sensor operated in this way can, for example, be part of an optical receiving device. The optical receiving device can be part of an optical detection system for a vehicle.

[0034] The electrical connection between the receiving pixels of the respective area can be provided, for example, for charge transport during readout of the receiving pixels. The reading of the receiving pixels can be performed, for example, by a readout device of the optical receiving device. The electrical connection can, in particular, comprise wiring and / or another physically provided connection. The shape of the area can depend on the arrangement of the receiving pixels on the receiving sensor.

[0035] The group of simultaneously read-out receive pixels to be activated is selected such that the group includes receive pixels that belong to at least two different regions of receive pixels. This also means that at least two of the receive pixels that are activated simultaneously have no electrical connection to each other. The pattern formed on the receive sensor by the simultaneously activatable receive pixels of a group therefore differs from the shape of the regions.

[0036] In one embodiment of the method, when a receiving pixel is saturated, electrical charge is transferred via the electrical connection to at least one neighboring receiving pixel within the region. Saturation results in electrical charge that cannot be absorbed by the corresponding receiving pixel. This charge is then transferred via the electrical connection to neighboring receiving pixels in the region. This process can continue across multiple receiving pixels. This effect is also referred to as blooming. The shape of the perceivable effect can typically have the shape of the region.

[0037] If the group of activated receive pixels is specifically selected so that receive pixels outside the range are also activated, i.e., read, it can be achieved that receive pixels that are not affected by overexposure are also read. This can improve the overall reception quality.

[0038] If the receiving sensor has receiving pixels arranged in rows and columns, the shape of the respective area can correspond, for example, to a respective row or a respective column. In one embodiment of the method, a respective area has, in particular, a column of receiving pixels. The column results from the orientation of the receiving sensor during operation relative to the earth's surface.

[0039] In one embodiment of the method, exactly one receiving pixel per line is activated during group-wise activation.

[0040] By activating the sensors in groups, especially in the central area of ​​the receiving sensor, those receiving pixels where the highest optical signal intensity is expected can be activated. This allows the highest accuracy in ambient detection to be achieved in this area.

[0041] In one embodiment of the method, during group activation in specific rows, particularly in rows located in the lower or upper area of ​​the receiving sensor, the receiving pixels are activated depending on the distance of a reflection point of the optical signal. This allows, for example, a shift in the reception range for close distances to be taken into account. For this purpose, the dependence on the distance of the reflection point also allows those receiving pixels for which the highest intensity is expected to be activated. It can also be taken into account that a lower accuracy of the environmental detection may be sufficient for objects above the road level.

[0042] The described method is advantageous for the operation of receiving sensors that have SPADs, since SPADs can easily saturate due to their high optical sensitivity. The described method can advantageously counteract this sensitivity to saturation. This is particularly the case when operating the receiving sensor in active optical detection systems, where saturation can occur during operation due to the emitted optical signal, especially in the presence of highly reflective objects in the environment.

[0043] Fiourenliste

[0044] In the following, embodiments of this application are further explained and described with reference to the figures.

[0045] Fig. 1 schematically shows an embodiment of an optical receiving device with an optical receiving sensor,

[0046] Fig. 2 schematically shows an embodiment of the optical receiving sensor with receiving pixels,

[0047] Fig. 3 schematically shows a vehicle with optical signals of an optical detection system,

[0048] Fig. 4 schematically shows the vehicle with the optical detection system.

[0049] The same reference numerals are used in the figures for identical or similar elements. Representations in the figures may not be to scale. Figure description

[0050] Figure 1 schematically shows an embodiment of an optical receiving device 10 with an optical receiving sensor 12 and a readout device 14.

[0051] The optical receiving sensor 12 has receiving pixels 16 arranged in rows and columns. The receiving pixels 16 have photosensitive elements that convert a received optical signal L into an electrical received signal 18. The received signal 18 is read out by the readout device 14 and made available for further processing. Reading out a respective receiving pixel 16 is also referred to as activating the respective receiving pixel 16.

[0052] Each receiving pixel 16 is configured as a so-called superpixel and comprises several individual pixels that are read out jointly by the readout device. Each individual pixel comprises a photosensitive element, e.g., a SPAD. Each superpixel thus comprises several photosensitive elements, e.g., SPADs. The individual pixels of the superpixel are read out jointly by the readout device 14.

[0053] The optical receiving device 10 can, in particular, be part of an active optical detection system 24, e.g., a lidar system. Especially with active optical detection systems 24 such as lidar systems, optical effects can occur that lead to overexposure in several receiving pixels 16. These effects occur particularly with highly reflective objects and the use of highly sensitive light sensors, such as SPADs, in the receiving pixels 16. These effects can lead to false detections and the obscuring of less reflective objects in the vicinity of the highly reflective objects.

[0054] Figure 2 schematically shows an embodiment of the optical receiving sensor 12 with a pixel field having the receiving pixels 16.

[0055] The receiving pixels 16 of the optical receiving sensor 12 are arranged in rows and columns. The columns of receiving pixels 16 form regions 22 within which the respective receiving pixels 16 have an electrical connection. An exemplary region 22 is shown hatched in Figure 2. The receiving pixels 16 within a region thus have an electrical connection to one another.

[0056] The receiving sensor 12 has a plurality of regions 22, wherein the receiving pixels 16 within a respective region 22 are contiguous and electrically connected to one another. The regions 22 of the receiving sensor 12 are also disjoint from one another.

[0057] In the case of a blooming effect, triggered, for example, by the reception of a reflection from a highly reflective object in an environment 32, a receiving pixel 16 of the area 22 can become saturated. This saturation can spread vertically along the column within the same area 22 due to blooming.

[0058] In Figure 2, an exemplary group 20 is shown in black. Each group 20 of activated receiving pixels 16 follows a pattern so that the area 22 affected by the overexposure effect is affected as little as possible.

[0059] In the example shown, for example, an optical transmitting device 26 emits a vertical line that successively scans the surroundings 32 in the horizontal direction. If the receiving sensor 12 shown in Figure 2 receives reflections from an object with very high reflectivity in the center of the receiving sensor 12 (black receiving pixel in the hatched area 22), a blooming effect is generated in the area 22. Therefore, the receiving pixels 16, e.g., SPAD superpixels, are not activated along the column of the area 22, but in a pattern that also includes receiving pixels 16 outside the area 22 affected by the blooming effect. The group 20 of activated receiving pixels 16 therefore does not coincide with the area 22 that contains the electrically interconnected receiving pixels 16, which are susceptible to blooming due to the electrical connection.

[0060] In particular, the activated receiving pixels 16 can be adjusted to the expected distances of the received reflections. For example, shorter distances can be expected in the lower area of ​​the measurement field, as these often measure ground points near the vehicle. The activated receiving pixels 16 are thus adjusted to the expected shift in the location of the reception of reflections from a short distance. This corresponds, for example, to the shift of the activated receiving pixels 16 as shown in Figure 2.

[0061] Other patterns can also be selected for the activated group 20, such as a zigzag pattern running left and right of the column of area 22. In particular, the selected pattern for the activated group 20 can also be used to reduce other undesirable effects in the system, such as lens flare or ghosting. Lens flare and ghosting are undesirable optical effects that occur when direct light is incident and are caused by scattering inside the lens.

[0062] Figure 3 schematically shows a vehicle 30 with optical signals L from an optical detection system 24. The distances between the reflections of the optical signals L depend on the solid angle from which the reflection is received. Different solid angles are in turn mapped to different heights of the receiving sensor 12. For example, the rows of receiving pixels 16 can correspond to different expected distances of reflections. The pattern of the group 20 can, on the one hand, be selected such that it only partially overlaps a respective area 22 and, on the other hand, can be selected such that it is adapted to the expected distances of the received reflections.

[0063] The pattern of Group 20 can be adjusted, for example, through calibration. Depending on the installation position in the vehicle and the associated distance from the track, Group 20 can then be calibrated accordingly.

[0064] In particular, the expected distances of the received reflections result from the installation position of the optical detection system 24 on the vehicle 30. From height and inclination, it can result, for example, that an area is located at the lower edge of the pixel field, where usually only the distance to the road is measured. The area with maximum intensity is therefore shifted due to the greater proximity compared to the column where the greatest intensity is expected in the center of the pixel field. In the center of the pixel field, the receiving pixel 16 for which the highest intensity is expected is activated. The highest intensity can be important in order to achieve the greatest range of environmental detection. If, for example, electrical blooming occurs on the receiving sensor 12 due to highly reflective objects, the light saturation appears in the area 22. In the embodiment shown in Figure 2, this is a vertical line, i.e. a column, of the pixel field.Due to the selected pattern of group 20, some receive pixels 16 may be less affected by the overexposure and therefore provide better detection results.

[0065] Figure 4 schematically shows the vehicle 30, e.g., a passenger car, with the active optical detection system 24, e.g., a lidar system.

[0066] The optical detection system 24 is arranged in the front region of the vehicle 30. The surroundings 32 detected by the optical detection system 24 are located in front of the vehicle 30 in the direction of travel. An object O is schematically depicted in the surroundings 32.

[0067] The optical detection system 24 has the optical transmission device 26, which transmits the optical signal L. The transmission device 26 can, in particular, have a light source for emitting laser light. The emitted optical signal L can, for example, be emitted in the form of vertical lines that successively scan the surroundings in a horizontal direction.

[0068] The optical detection system 24 further comprises the optical receiving device 10 for receiving the reflected optical signal L. The receiving device 10 comprises the receiving sensor 12 with the receiving pixels 16 for receiving the optical signal L. Each receiving pixel 16 can, for example, have several SPADs.

[0069] The transmitted and received reflected optical signal L can be evaluated in a computing device 28, e.g., to detect the object O and / or to determine the distance to the object O. The computing device 28 can also monitor and control the transmission process in the transmission device 26 and the reception process in the reception device 10. The computing device 28 can control the optical reception sensor 12 such that it is operated such that the reception pixels 16 are activated in groups, wherein the respective groups 20 of activated reception pixels 16 comprise reception pixels 16 from at least two different areas 22. In the example shown, the environment 32 in front of the vehicle 30 in the direction of travel can be monitored. It is also possible to arrange the detection system 24 in other areas of the vehicle 30, for example, in the rear area and / or in side areas.It is also possible to arrange several detection systems 24 on the vehicle 30, in particular in corner areas of the vehicle 30.

[0070] With the active optical detection system 24, stationary or moving objects 0, in particular vehicles, persons, animals, plants, obstacles, road surface irregularities, in particular potholes or stones, road markings, traffic signs, open spaces, in particular parking spaces, precipitation or the like, can be detected in the environment 32.

Claims

CLAIMS 1. An optical receiving device (10) comprising an optical receiving sensor (12) and a readout device (14), wherein the receiving sensor (12) has a plurality of receiving pixels (16), each of which is configured to convert an optical signal (L) into an electrical receiving signal (18), wherein the receiving pixels (16) are arranged in at least two regions (22), wherein the receiving pixels (16) are contiguous within a respective region (22) and have an electrical connection to one another, wherein the receiving pixels (16) can be activated in groups, wherein the readout device (14) activates the respective receiving pixels (16) by reading out the respective electrical receiving signal (18), wherein the respective groups (20) of activated receiving pixels (16) comprise receiving pixels (16) from at least two different regions (22).

2. Optical receiving device according to claim 1, wherein when a receiving pixel (16) is saturated, electrical charge is transferred via the electrical connection to at least one adjacent receiving pixel (16) within the area (22).

3. Optical receiving device according to claim 1 or 2, wherein the regions (22) are disjoint.

4. Optical receiving device according to one of the preceding claims, wherein the plurality of receiving pixels (16) are arranged in rows and columns on the receiving sensor (12) and wherein a respective region (22) has a column of receiving pixels (16).

5. Optical receiving device according to claim 4, wherein the respective group (20) of activated receiving pixels (16) has exactly one receiving pixel (16) per line.

6. Optical receiving device according to claim 5, wherein the respective group (20) of activated receiving pixels (16) comprises, in certain rows, in particular in rows located in the central region of the receiving sensor (12), those receiving pixels (16) of the row in which the highest intensity of the optical signal (L) is expected.

7. Optical receiving device according to one of the preceding claims, wherein at least one receiving pixel (16) is designed as a superpixel which has a plurality of individual pixels, wherein when an activated superpixel the individual pixels of the superpixel are read out together.

8. Optical receiving device according to one of the preceding claims, wherein at least one receiving pixel (16) has at least one SPAD.

9. Optical detection system (24) for a vehicle (30), comprising an optical receiving device (10) according to one of the preceding claims, further comprising an optical transmitting device (26) which is configured to transmit the optical signal (L), wherein the optical detection system (24) in particular comprises a lidar system.

10. Optical detection system according to claim 9, wherein in certain lines, in particular in lines located in the lower or upper region of the optical receiving sensor (12), the affiliation of the receiving pixels (16) to the respective group (20) of activated receiving pixels (16) depends on a distance of a reflection point of the optical signal (L) from the optical detection system (24).

11. Vehicle (30) with an optical detection system (24) according to one of claims 9 or 10.

12. A method for operating an optical receiving sensor (12), wherein the receiving sensor (12) has a plurality of receiving pixels (16), each of which is configured to convert an optical signal (L) into an electrical receiving signal (18), wherein the receiving pixels (16) are arranged in at least two regions (22), wherein the receiving pixels (16) are contiguous within a region (22) and have an electrical connection to one another, the method comprising: activating the receiving pixels (16) in groups, wherein the respective receiving pixels (16) are activated by reading out the respective electrical receiving signal (18), wherein the respective groups (20) of activated receiving pixels (16) have receiving pixels (16) from at least two different areas (22).

13. The method according to claim 12, wherein when a receiving pixel (16) is saturated, electrical charge is transferred via the electrical connection to at least one adjacent receiving pixel (16) within the area (22).

14. Method according to one of claims 12 or 13, wherein in the group-wise activation exactly one receiving pixel (16) per line is activated.

15. Method according to one of claims 12 to 14, wherein in the group-wise activation in certain rows, in particular in rows located in the central region of the receiving sensor (12), those receiving pixels (16) are activated in which the highest intensity of the optical signal (L) is expected.

16. Method according to one of claims 12 to 15, wherein in the group-wise activation in certain rows, in particular in rows located in the lower or upper region of the receiving sensor (12), the receiving pixels (16) are activated as a function of the distance of a reflection point of the optical signal (L).

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