Multi-pulse lidar system and method for detecting objects in an observation region

Abstract

The invention relates to a multi-pulse lidar system (100) for detecting at least one object (400), comprising a transmitting device (110) with at least one laser source (111), a receiving device (140) with a detection surface (141) comprising a line or matrix arrangement of sub-detectors (143) for receiving a transmitted laser beam (210) reflected and / or scattered on an object (400) in an observation region (300), wherein the receiving device (140) is configured to image a detection region (310n) detected by the transmitted laser beam (210) in the form of an image point (230n) on the detection surface (141), a scanning device (120) for generating a scanning movement (122) of the transmitted laser beam (210) and the received laser beam (220), and a control device (130) for determining distance information of the detection region (310n), wherein the control device (130) is configured to select an angular range (307) of the observation region (300) and to group the sub-detectors (142i,j) into a first macro-pixel (160n) for analysis for at least one first single laser pulse with which a first detection region (310n) can be illuminated, and to group the sub-detectors (142i,j) into at least one second macro-pixel (160n) for analysis for at least one second single laser pulse with which at least a second detection region (310n) can be illuminated, wherein the sub-detectors (142i,j) of the first macro-pixel and of the at least one second macro-pixel (160n) can image the selected angular range (307) respectively, and wherein the sub-detectors (142i,j) are each detected by one image point (230n) currently imaged on the detection surface (141).

Description

TECHNICAL FIELD

[0001] The present application relates to a multi-pulse lidar system for detecting at least one object in an observation region and a method for detecting at least one object in an observation region by means of a multi-pulse lidar system. BACKGROUND

[0002] DE 10 2017 223 102 A1 discloses a multi-pulse lidar system for detecting objects in an observation region, comprising a transmitting device with at least one laser source for generating a transmitting laser beam from a temporal sequence of individual laser pulses, which respectively illuminate a spatial angle confined to a part of the observation region and are sampled in at least one sampling point, a receiving device with a detection surface comprising a line-wise or matrix-wise arrangement of sub-detector groups consisting of a plurality of sub-detectors arranged side by side in a first extension direction, for receiving the transmitting laser beam reflected and / or scattered in the form of a receiving laser beam on objects in the observation region of the multi-pulse lidar system, wherein the receiving device is configured for imaging the sampling points detected by the transmitting laser beam in the form of image points on the detection surface, a scanning device for generating a scanning movement of the transmitting laser beam in a scanning direction for stepwise sampling the entire observation region along a plurality of sampling points successive to each other in the scanning direction, wherein the scanning movement of the transmitting laser beam is configured for imaging the image points offset along the line-wise or matrix-wise arrangement of sub-detectors on the detection surface, respectively, in the case of individual laser pulses successive in time, and a control device for determining distance information of the sampling points from the propagation times of the individual laser pulses, wherein the control device is configured for jointly evaluating the sub-detectors detected by the image points currently imaged on the detection surface in the form of macro-pixels individually assigned to the corresponding image points. SUMMARY

[0003] This invention relates to a multi-pulse lidar system for detecting at least one object within an observation area. The multi-pulse lidar system includes a transmitting device having at least one laser source for generating a transmitted laser beam from a time sequence of at least two individual laser pulses, each individual laser pulse illuminating a detection area confined to a portion of the observation area; a receiving device having a detection surface comprising a row or matrix arrangement of sub-detectors, the sub-detector arrangement consisting of a plurality of sub-detectors arranged side-by-side in a first extending direction; the receiving device for receiving the transmitted laser beam reflected and / or scattered by the object within the observation area of ​​the multi-pulse lidar system in the form of a received laser beam, wherein the receiving device is configured to image the detection area detected by the transmitted laser beam onto the detection surface as image points. The multi-pulse lidar system further includes a scanning device for generating scanning motion of the transmitted and received laser beams in a scanning direction for progressively sampling the entire observation area along a plurality of successive detection areas in the scanning direction; and a control device for determining distance information of the detection area based on the propagation time of the corresponding individual laser pulses. The control device is configured to: select an angular range of the observation area; divide the sub-detectors into first macropixels for analysis processing by at least one first single laser pulse, which illuminates a first detection area; and divide the sub-detectors into at least one second macropixel for analysis processing by at least one second single laser pulse, which illuminates at least a second detection area. Here, the sub-detectors, using the first macropixel and at least one second macropixel, can respectively image the selected angular range, and each sub-detector is detected by an image point currently imaged on the detection surface.

[0004] A multi-pulse lidar system is a lidar system that illuminates the detection area using multiple short, consecutive, low-power laser pulses. A suitable detector signal with a sufficient signal-to-noise ratio can be obtained by accumulating the individual measurements. In contrast, a single-pulse lidar system samples each detection area individually using a single laser pulse. However, this requires single laser pulses with relatively high power, thus necessitating a correspondingly high-power laser source. Conversely, multi-pulse lidar systems have significantly lower laser power.

[0005] Multi-pulse lidar systems are primarily used to detect objects in the environment surrounding a vehicle. During scanning, the transmitted laser beam moves progressively along the scanning direction, allowing objects within the observation area to be detected. The relative position of the detected object with respect to the vehicle can be determined using the corresponding angle of the transmitted laser beam and the distance information obtained by measuring the propagation time of a single laser pulse.

[0006] The receiving device with a detection surface is particularly constructed as a SPAD detector. Here, SPAD stands for Single Photon Avalanche Photodiode. A SPAD detector can have so-called SPAD cells as sub-detectors. A row-type sub-detector arrangement includes multiple sub-detectors arranged side-by-side in a first extending direction. A matrix-type sub-detector arrangement includes multiple sub-detectors arranged side-by-side in a first extending direction and multiple sub-detectors arranged sequentially in a second extending direction.

[0007] The advantages of this invention are that, although multiple pulses are used for a single measurement, the same lateral resolution as in a single-pulse lidar system can be achieved, with improved object separability. In particular, better object separability in the horizontal direction can be achieved. Smaller objects, such as lost goods, can be detected more effectively over a larger range—i.e., at a greater distance from the multi-pulse lidar system. Furthermore, it prevents the negative impact of severely interfering background light on the measurement. Moreover, the components of the multi-pulse lidar system can be implemented simply. The overhead for analyzing and processing measurement data—such as determining distance information—can be kept low. The required storage space and computational overhead can be minimized.

[0008] In an advantageous configuration of the invention, the control device is further configured to group at least one second macropixel independently of the first macropixel. In particular, distance information can be determined based on the second macropixel independently of the first macropixel. The control device is specifically configured to create and analyze a first histogram for the first macropixel and to create and analyze a second histogram for the second macropixel, wherein the second histogram can be created and analyzed independently of the first histogram. The second histogram can be created and analyzed without considering the first histogram. In other words, the first histogram is not cached, but rather remains unconsidered. The advantage of this configuration is that it keeps the overhead for analyzing and processing measurement data low. It requires minimal storage space and computational overhead.

[0009] In another embodiment, the transmitting device includes multiple laser sources, the detection areas of which are arranged orthogonally to each other with respect to the scanning direction. Here, the detection surface includes a separate sub-detector assigned to each laser source, wherein the sub-detectors are arranged orthogonally to each other with respect to the scanning direction. This improves the vertical resolution of the lidar system.

[0010] The present invention also relates to a method for detecting at least one object within an observation area using a multi-pulse lidar system. The method includes the steps of: generating a transmitted laser beam in the form of a time sequence of at least two individual laser pulses, wherein the transmitted laser beam illuminates a detection area limited to a portion of the observation area with each individual laser pulse; generating a scanning motion of the transmitted and received laser beams in a scanning direction, the scanning motion causing progressive sampling of the entire observation area in a plurality of successive detection areas in the scanning direction; and receiving the received laser beam, generated by reflection and / or scattering of the transmitted laser beam on an object within the observation area, on a detection surface having a row or matrix arrangement of a plurality of sub-detectors arranged side-by-side in a first extending direction, wherein the object currently detected by the transmitted laser beam... The region is imaged on the detection surface in the form of image points; an angular range of the observation region is selected; a sub-detector is divided into a first macro-pixel by at least one first single laser pulse, the first single laser pulse illuminating a first detection region, and a sub-detector is divided into at least one second macro-pixel by at least one second single laser pulse, the second single laser pulse illuminating at least one second detection region, wherein the sub-detectors of the first macro-pixel and at least one second macro-pixel respectively image the selected angular range and are respectively detected by an image point currently imaged on the detection surface; and the first macro-pixel and at least one second macro-pixel are analyzed and processed to determine the distance information of the selected angular range based on the propagation time of the corresponding single laser pulse.

[0011] In an advantageous configuration of the invention, the sub-detectors are divided into at least one second macro-pixel independently of dividing them into first macro-pixels. In particular, distance information is determined based on the second macro-pixels independently of the first macro-pixels. Specifically, a first histogram is created and analyzed for the first macro-pixels, and a second histogram is created and analyzed for the second macro-pixels independently of the first histogram. The second histogram can be created and analyzed without considering the first histogram. In other words, the first histogram is not cached; instead, it remains unconsidered. The advantage of this configuration is that it keeps the overhead for analyzing and processing measurement data low. It requires minimal storage space and computational overhead.

[0012] The present invention also relates to a computer program configured to implement all the steps of the described method.

[0013] The present invention also relates to a machine-readable storage medium on which the described computer program is stored. Attached Figure Description

[0014] Embodiments of the invention are described in more detail below with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or functionally equivalent elements. The drawings show:

[0015] Figure 1 A schematic perspective view of an embodiment of a multi-pulse lidar system;

[0016] Figure 2 : A schematic diagram of a rotating lidar system scanning vehicles positioned in its observation area;

[0017] Figure 3 : A description of the grouping of the first macropixel and subsequent macropixels;

[0018] Figures 4-6 A schematic diagram of a lidar system according to the present invention is used to illustrate the sampling process of an object using three consecutive single laser pulses.

[0019] Figures 7-9 A schematic diagram of the sampling process performed on the object;

[0020] Figure 10 An embodiment of a method for detecting at least one object within an observation region. Detailed Implementation

[0021] Figure 1 An exemplary macro lidar system 100 with a rotating sensor head 101 is shown, the sensor head having multiple transmitting and receiving units arranged at different angles, wherein only the transmitting unit 110 is shown in this example. Here, the sensor head 101 performs a rotating scanning motion 122, wherein, in this example, the rotation axis 102 extends parallel to the Z-axis. With this arrangement, the horizontal image resolution of the lidar system is determined by the rotational motion and the measurement rate. Conversely, the vertical image resolution is limited by the number of receiving units and the corresponding angular distance. In this embodiment, the sensor head 101 performs a complete 360° rotation. However, for each embodiment, the scanning motion can be limited to a defined angular range.

[0022] Figure 2 Show Figure 1This is a schematic diagram of a macro lidar system 100 during a scanning process, in which an object 400 (in this case, a vehicle) arranged in an observation area 300 of the lidar system 100 is sampled by means of laser radiation 200. The lidar system 100 has a rotating sensor head 101, which includes a transmitting device 110 having at least one laser source 111 and a receiving device 140 having a detection surface 141. The detection surface 141 includes a row or matrix arrangement of sub-detectors 143 for each laser source, the sub-detector arrangement consisting of a plurality of sub-detectors 142 arranged side-by-side in a first extending direction 144. n Composition. For clarity, in Figure 2 The image only shows 142 with only three sub-detectors. n The row-shaped sub-detectors are arranged in 143.

[0023] In this embodiment, the sensor head 101 also includes an optical imaging device 150. This may be, for example, one or more optical lens elements by which the laser beams 210, 220 are shaped in a desired manner. Furthermore, as in this embodiment, the sensor head 101 may have a beam splitter 121 for superimposing or separating the transmitted and received laser beams 210, 220. This optical beam splitter 121 may, for example, be constructed in the form of a semi-transparent mirror.

[0024] like Figure 2 As further shown, the lidar system 100 typically also includes a control device 130 for controlling the transmitting and receiving devices 110, 140. In this example, the control device 130 also includes a measuring device for determining the propagation time of a single transmitted and received laser pulse, and an analysis and evaluation device for determining distance information of the sampling point using the measured propagation time. Depending on the implementation, the control device 130 or individual components of the control device may be arranged outside the sensor head 101 and connected to corresponding devices in the sensor head 101 via corresponding signal and data lines. Alternatively, the control device 130 or individual components of the control device may be housed inside the sensor head 101.

[0025] During operation of the lidar system 100, each laser source of the transmitting device 110 generates its own transmitted laser beam 210 in the form of a time sequence of short, single laser pulses. Here, the transmitted laser beam 210 illuminates a solid angle of a detection area 310 defining a corresponding single laser pulse, typically only a relatively small segment of the entire observation area 300 of the lidar system 100. Sampling of the entire observation area 300 is achieved through a rotating scanning motion 122 and the accompanying gradual shifting of the detection area 310 of successive single laser pulses. Figure 2An exemplary measurement sequence is shown, which has three individual laser pulses emitted sequentially in time and their corresponding detection regions 310-1 to 310-3. Here, detection regions 310-1 to 310-3 are marked with dashed lines. In this embodiment, the detection regions 310-1 to 310-3 of the transmitted laser beam 210 are shown as circles. However, depending on the application, the cross-section of the transmitted laser beam 210 defining the shape of the detection region 310 may also have other configurations, such as elliptical or approximately square or rectangular. Due to the scanning motion 122 of the sensor head 101, the individual laser pulses are emitted at different angles, such that the transmitted laser beam 210 always moves over the separately sampled object 400 with its current detection region 310 in predetermined angular steps.

[0026] As in Figure 2 As shown, the transmitted laser beam 210, reflected from or scattered back from object 400, is received in sensor head 101 as a received laser beam 220 and imaged onto detector surface 141. Due to scanning motion 122, the current detection area 310 is imaged on detector surface 141 by a defined distance as laser pulses follow one another.

[0027] Figure 3 A timing diagram is shown, illustrating the grouping of the first macropixel and subsequent macropixels. Figure 2 Unlike other embodiments, in this one, the detection surface 141 has a matrix arrangement of sub-detectors 143, comprising a total of 21 sub-detectors 142i,j arranged side-by-side in the first extending direction 144 and a total of eight sub-detectors 142i,j arranged sequentially in the second extending direction 145. To detect distance information from a specific angular range 307 of the observation area 300, this angular range 307 is first selected. This angular range 307—or in other words, the spatial angle—can be defined, for example. Figure 2 The detection area 310-1 is shown in the current example. In this example, the middle sub-detector 142i,j of the sub-detector arrangement 143 is configured to image the selected angular range 307, which is exemplarily shown between two vertical lines marked by brackets 307.

[0028] Now, the first detection area 310 is illuminated by the first single laser pulse. n The transmitted laser beam reflected from or scattered back from the object is received at time point 301 as a received laser beam and serves as image point 230. nThe image is projected onto the detector surface 141. The lowermost sub-detector arrangement 143 indicates which sub-detectors 142i,j are configured to image the angle range 307 at time point 301, respectively, by an image point 230 currently imaged on the detector surface 141. n Detected. These sub-detectors are shown in dark shades as sub-detectors 142i,jA. Sub-detector 142i,jB, located to the right of sub-detector 142i,jA, is also configured to image the angle range 307, but at time point 301, it is not currently imaged on the detector surface 141 at image point 230. n Detected. At time point 301, the sub-detector 142i,jC, shown in light shade to the left of sub-detector 142i,jA, is currently imaged on detector surface 141 by image point 230. n Detected, but not constructed for imaging the 307 angular range. Sub-detectors 142i,jA are grouped into the first macropixel 160. n The signals from the grouped sub-detectors 142i,jA are collectively assigned to the histogram belonging to the first macropixel 160-1.

[0029] The second detection area 310 was then illuminated by a second single laser pulse. n The transmitted laser beam reflected from or scattered back from the object is received at time point 302 as a received laser beam and serves as image point 230. n The image is projected onto the detector surface 141. The second sub-detector arrangement 143 from the bottom indicates which sub-detectors 142i,j are configured to image the angular range 307 at time point 302, respectively, by an image point 230 currently imaged on the detector surface 141. n Detected. These sub-detectors are sub-detectors 142i,jA, shown in dark shading. As described for time point 301, the sub-detectors shown in dark shading are now grouped into second macropixels 160-2 for time point 302. Here, the second macropixels 160-2 are grouped independently of the first macropixels 160-1. The signals of the sub-detectors 142i,jA grouped for time point 302 are collectively assigned to the histogram associated with the second macropixels 160-2. Here, the second histogram is created and analyzed independently of the histogram of the first macropixels 160-1. This keeps the overhead for analyzing and processing measurement data low. This also applies to time points 303 to 306. For clarity, only for time point 306, except for time point 301, are sub-detectors 142i,jA, 142i,jB, and 142i,jC, and image point 230 marked. n And the sixth macro pixel 106-6.

[0030] Figure 3 This demonstrates how image point 230 is generated by scanning motion in scanning direction 123. n The impression of movement on the sub-detector arrangement 143 allows for the realization of multiple detection regions 310 sequentially along the scanning direction 123 through this scanning motion. n Stepwise sampling of the entire observation area also produces the following impression: 160 macropixels. n Moving on the sub-detector arrangement 143, wherein the macropixels simultaneously change their size. This can be used to group individual macropixels 160. n The number of sub-detectors 142i,jA varies depending on time points 301 to 306. Therefore, this number increases from time point 301 to time point 303. For example, at time point 303, all sub-detectors 142i,j configured to image the angular range 307 are currently imaged on the detector surface 141 at image point 230. n Detected. At this time, the detection area is 310. n Equivalent to an angle range of 307°. Detection area 310°. n It is precisely located within the angle range 307. In this example, at this time point, all sub-detectors 142i,j configured to image the angle range 307 are able to form the third macropixel 160-3. From time point 303 to time point 306, the number of sub-detectors 142i,jA decreases again.

[0031] Figures 4 to 6 A schematic diagram of a lidar system according to the present invention is shown to illustrate the sampling process of an object using three consecutive single laser pulses. For this purpose, Figures 4 to 6 It has been shown that Figure 2 The short scan sequence shown in the image includes sampling of vehicle 400 using three single laser pulses. Figure 4 This illustrates a first single measurement in which vehicle 400 is illuminated by a first single laser pulse. Here, the first single laser pulse illuminates a first detection area 310-1, which is confined to a portion of the observation area 300. For in Figures 4 to 6 The exemplary scan sequence shown in the diagram indicates that the detection region 310-1 corresponds to the selected angular range 307. Figure 4 The first detection area 310-1 detected by the transmitted laser beam 210 is represented by image point 230. n The image is formed on the detector surface 141 in the form of image point 230. n This illuminates the sub-detectors 142i,j in the matrix-style sub-detector arrangement 143. Figure 4A total of 64 sub-detectors, labeled as sub-detectors 142i,jA shown in dark shading, are included. For the first single measurement, the first detection area 310-1 lies entirely within the selected angular range 307 of the observation area 300. Therefore, the selected angular range 307 can be imaged using all the sub-detectors 142i,jA illuminated by the image point. The sub-detectors 142i,jA are grouped into first macropixels 160. n Used for analysis and processing. Therefore, the first macropixel 160 n Includes sub-detectors 142i,jA, which are imaged by point 230 on the detector surface 141. n Detected. The signals from the grouped sub-detectors 142i,jA are collectively assigned to the first macropixel 160. n Histogram 170 n .

[0032] exist Figure 5 In the method state shown, the transmitted laser beam 210 moves further in the scanning direction 123 due to the scanning motion 122. Therefore, the currently emitted second single laser pulse has a detection area 310-2 offset by a specific angular amount in the scanning direction 123. Therefore, the first image point 230... n The position on the detection surface 141 is also offset by a defined amount. Here, image point 230 n The offset is directly related to the imaging characteristics of the optical components and the corresponding angular difference between individual measurements, and therefore to the scanning speed and measurement rate. In this embodiment, these parameters are coordinated with each other such that image point 230 n In subsequent individual measurements, the image is imaged onto the detector surface at an offset distance, which corresponds as precisely as possible to the lateral width of sub-detectors 142i,j. This ensures that sub-detectors 142i,jA are always explicitly assigned to macropixel 160. n One macro pixel. This also applies to the following implementation: in which image point 230 is measured in a subsequent single measurement. n The offset step size when imaging on the detection surface is an integer multiple of the lateral width of the sub-detector 142i,j. However, depending on the application, the corresponding parameters of the lidar system can also be such that the offset step size when the image point is imaged on the detection surface in a subsequent single measurement is a fraction of the lateral width of the sub-detector. Alternatively, a lidar system can be implemented where, in the lidar system, image point 230... n The offset on the detection surface is not in a reasonable proportion to the lateral width of the sub-detectors 142i,j.

[0033] exist Figure 5The first detection area 310-2 detected by the transmitted laser beam 210 is represented by image point 230. n The image is formed on the detector surface 141 in the form of image point 230. n This illuminates a total of 64 sub-detectors in the matrix arrangement 143 of sub-detectors 142i,j. However, for the second single measurement, the second detection region 310-2 is no longer entirely within the selected angular range 307 of the observation region 300. Only 56 sub-detectors 142i,jA configured to image the angular range 307 remain as image points 230 currently imaged on the detection surface 141. n Detected. Figure 5 The sub-detector 142i,jC, which is arranged to the right of sub-detector 142i,jA and is shown in light shade, is imaged by point 230 on the detector surface 141. n The sub-detectors 142i,jB, located to the left of sub-detectors 142i,jA, are configured to image the angle range 307, but are not currently imaged on the detector surface 141 at image point 230. n Detected. Sub-detector 142i,jA is grouped into the second macropixel 160. n Accordingly, the second macropixel is 160. n It also includes information from a portion of region 308 within the selected angle range 307. The signals from the grouped sub-detectors 142i,jA are collectively assigned to the second macropixel 160. n The second histogram 170 n A second histogram (170) is created and analyzed independently of the histogram of the first macropixel. n .

[0034] Figure 6 This shows the method status during the third single measurement, which follows... Figure 5 Following the second single measurement shown, the transmitted laser beam is moved to the right by a further angular amount due to the scanning motion, so that the corresponding detection area 310-3 is now relative to... Figure 4 The first single measurement shown moves by a further amount. Therefore, the current image point 230... n The position on the probe surface 141 is also offset by a defined amount. This offset is related to... Figure 5 The width of the image is twice that of sub-detector 142i,j. Current image point 230 nThis illuminates a total of 64 sub-detectors in the matrix-style sub-detector arrangement 143, comprising sub-detectors 142i,j. However, for the third single measurement, the third detection region 310-3 is even less located within the selected angular range 307 of the observation region 300. Only 40 sub-detectors 142i,jA configured to image the angular range 307 are still imaged at image point 230 on the detector surface 141. n Detected. Figure 6 The sub-detector 142i,jC, which is arranged to the right of sub-detector 142i,jA and is shown in light shade, is imaged by point 230 on the detector surface 141. n The sub-detectors 142i,jB, located to the left of sub-detectors 142i,jA, are configured to image the angle range 307, but are not currently imaged on the detector surface 141 at image point 230. n Detected. Sub-detector 142i,jA was grouped into the third macropixel 160. n Accordingly, the third macropixel is 160. n It also includes information from a portion of region 309 within the selected angle range 307. The signals from the grouped sub-detectors 142i,jA are collectively assigned to the third macropixel 160. n Histogram 170 n A third histogram (170) is created and analyzed independently of the histograms of the first and second macropixels. n .

[0035] Figures 7 to 9 This diagram illustrates the sampling process of object 400 located within the selected angle range 307. It shows the rotational scanning motion and the macropixel 160. n The correlation between the offsets on the detection surface 141 of the sub-detector arrangement 143 and the macropixel 160 n The dimensions change simultaneously. Therefore, Figures 7 to 9 The scanning process is illustrated by a sequence of three individual measurements. A simplified embodiment of sensor head 101 is shown, wherein laser beam 235 is directly imaged onto detector surface 141 by means of optical imaging device 150 without deflection caused by beam splitter. The emitted transmit laser beam 210 detects object 400 located within a selected angle range 307. The transmitted laser beam 210 is reflected back from object 400 and is received again by sensor head 101 of lidar system 100 as a received laser beam. Image point 230 nThe image is formed on the detector surface 141. For better illustration, the detector surface 141 is shown not only in a side view but also in a top view. In this embodiment, the detector surface is constructed as a two-dimensional sub-detector arrangement 143 in a 12×8 matrix form. In the current example, image point 230... n exist Figures 7 to 9 In each of the individual measurements shown, the image is imaged on the central region of the sub-detector arrangement 143. This region is marked by a thick border. For example, it is only arranged at this image point 230. n Sub-detectors 142i,j in the array are active.

[0036] For the first single measurement, Figure 7 This shows which sub-detectors in sub-detectors 142i,j are configured to image the angular range 307 and are currently imaged on the detector surface 141 at image point 230. n Detected. These sub-detectors are eight sub-detectors 142i,jA. The eight sub-detectors 142i,jB arranged to the left of sub-detectors 142i,jA, although also configured to image the angular range 307, were not currently imaged on the detector surface 141 at image point 230 during the first single measurement. n Detected. For example, sub-detector 142i,jB is currently inactive. The eight sub-detectors 142i,jC arranged to the right of sub-detector 142i,jA are currently imaged on detector surface 141 at image point 230. n Detected, but not constructed for imaging the 307 angular range. Eight sub-detectors 142i,jA are grouped into the first macropixel 160. n The signals from the grouped sub-detectors 142i,jA are collectively assigned to the first macropixel 160. n The histogram.

[0037] Figure 8 Shown in the next second single measurement Figure 7 The arrangement is as follows. Here, the transmitting laser beam 210 moves further in the scanning direction 123 due to the scanning motion 122. Figure 8 In the middle, 16 sub-detectors 142i,jA are configured to image an angle range of 307 and are currently imaged on the detector surface 141 at image point 230. n Detected. 16 sub-detectors 142i,jA were grouped into the second macropixel 160. n Independent of the first macropixel, the second macropixel is 160. n The signals from the grouped sub-detectors 142i,jA are collectively assigned to the second macropixel 160. n Histogram. Second macropixel 160 nTherefore, it is offset in the scanning direction 123 and is 160 degrees from the first macropixel. n Larger, meaning it includes a higher number of sub-detectors 142i,jA. A second histogram is created and analyzed independently of the histogram of the first macropixel.

[0038] Figure 9 Shown in the next third single measurement Figure 7 and Figure 8 The arrangement is as follows. Here, the transmitting laser beam 210 moves further in the scanning direction 123 due to the scanning motion 122. Figure 9 In the middle, eight sub-detectors 142i,jA are configured to image an angle range of 307 and are currently imaged on the detector surface 141 at image point 230. n Detected. The eight sub-detectors 142i,jB arranged to the right of sub-detector 142i,jA, although also configured to image the angular range 307, were not currently imaged on the detector surface 141 at image point 230 during the third single measurement. n Detected. For example, sub-detector 142i,jB is currently inactive. The eight sub-detectors 142i,jC arranged to the left of sub-detector 142i,jA are currently imaged on detector surface 141 at image point 230. n Detected, but not constructed for imaging an angle range of 307. Eight sub-detectors 142i,jA are grouped into a third macropixel 160. n Independent of the first macropixel and independently of the second macropixel, the third macropixel is 160. n The signals from the grouped sub-detectors 142i,jA are collectively assigned to the third macropixel 160. n Histogram. Third macropixel 160 n Therefore, it is offset in the scanning direction 123 and is 160 degrees from the second macropixel. n Smaller, meaning it includes a lower number of sub-detectors 142i,jA. A third histogram is created and analyzed independently of the histogram of the first macropixel and independently of the histogram of the second macropixel.

[0039] Figure 10An embodiment of method 1000 is shown again in summary for detecting at least one object within an observation area using a multi-pulse lidar system. Method 1000 begins at step 1001. The method includes the following additional steps: generating 1002 a transmitted laser beam in the form of a time sequence of single laser pulses, wherein the transmitted laser beam illuminates a detection area limited to a portion of the observation area with each single laser pulse; generating 1003 a scanning motion of the transmitted laser beam in a scanning direction, the scanning motion causing progressive sampling of the entire observation area in a plurality of detection areas successive to each other in the scanning direction; receiving 1004 a received laser beam generated by reflection and / or scattering of the transmitted laser beam on an object within the observation area at a detection surface, the detection surface having a row or matrix arrangement of a plurality of sub-detectors arranged side-by-side in a first extending direction, wherein the detection area currently detected by the transmitted laser beam is... Image points are formed on the detection surface; an angular range of the observation area is selected (1005); sub-detectors are grouped (1006) into first macropixels for at least one first single laser pulse, which illuminates the first detection area; and sub-detectors are grouped (1007) into at least one second macropixel for at least one second single laser pulse, which illuminates at least one second detection area, wherein the sub-detectors of the first macropixel and at least one second macropixel respectively image the selected angular range and are respectively detected by an image point currently imaged on the detection surface; the first macropixel and at least one second macropixel are analyzed (1008) to determine the distance information of the selected angular range based on the propagation time of the corresponding single laser pulse. The method ends at step 1009.

Claims

1. A multi-pulse lidar system (100) for detecting at least one object (400) in an observation area (300), the multi-pulse lidar system comprising: • A transmitting device (110) having at least one laser source (111) for generating a transmitted laser beam (210) from a time sequence of at least two individual laser pulses, each individual laser pulse illuminating a detection area (310) confined to a portion of the observation area (300). n ), • A receiving device (140) having a detection surface (141), the detection surface comprising a row or matrix arrangement of sub-detectors (143), the sub-detector arrangement consisting of a plurality of sub-detectors (142) arranged side by side in a first extending direction (144). i,j The receiving device is configured to receive a transmitted laser beam (210) reflected and / or scattered on the object (400) in the observation area (300) of the multi-pulse lidar system (100) in the form of a receiving laser beam (220). The receiving device (140) is configured to receive the detection area (310) detected by the transmitted laser beam (210). n ) with image point (230 n The image is formed on the detection surface (141) in the form of an image. • A scanning device (120) for generating scanning motion (122) of the transmitted laser beam (210) and the received laser beam (220) in a scanning direction (123), for scanning multiple detection areas (310) that are sequentially connected along the scanning direction (123). n Sampling was performed gradually across the entire observation area (300), and • Control device (130), the control device being used to determine the detection area (310) based on the propagation time of the corresponding single laser pulse. n Distance information, The control device (130) is characterized in that it is configured to: select a specific angular range (307) of the observation area (300), wherein the angular range (307) is capable of defining the detection area (310). n ),and • For at least one first single laser pulse, the sub-detector (142) i,j-A The first macro-pixel (160-1) is divided into two parts for analysis and processing. The first single laser pulse can illuminate the first detection area (310). n The sub-detector is able to image the selected angular range (307) and the sub-detector is imaged by the image point (230) on the detection surface (141) at the current first time point (301). n ) detected that, among them, the grouped sub-detectors (142) i,j-A The signals are collectively assigned to the histogram belonging to the first macropixel (160-1); and • For at least one second single laser pulse, the sub-detector (142) i,j-A ) is composed of at least one second macro pixel (160) n ) is used for analysis and processing, and the second single laser pulse can illuminate at least the second detection area (310). n The sub-detector is capable of imaging the selected angular range (307) and the sub-detector is formed by an image point (230) on the detection surface (141) currently imaged for at least one second time point (302 to 306). n ) detected that, among them, the grouped sub-detectors (142) i,j-A The signal is jointly assigned to the at least one second macropixel (160). n The second histogram of ) and • In the analysis and processing of the first macro pixel (160-1) and the at least one second macro pixel (160) n In the case of ), the distance information of the selected angle range (307) is determined based on the propagation time of the corresponding single laser pulse. • Among them, the sub-detector (142) used to assemble the first macropixel (160-1) at the first time point (301) i,j-A The number of pixels used to compose the at least one second macropixel (160) for the at least one second time point (302 to 306) is the same as the number used to compose the at least one second macropixel (160) for the at least one second time point (302 to 306). n ) sub-detectors (142 i,j-A The quantities are different. • The control device (130) is further configured to control the at least one second macropixel (160) independently of the first macropixel (160-1). n Grouping allows for the creation and analysis of histograms associated with the at least one second macropixel (160-1) independently of the histogram associated with the first macropixel (160-1). n Histogram of ).

2. A method for detecting at least one object in an observation area using a multi-pulse lidar system, the method comprising the steps of: • Generate (1002) a transmitted laser beam in the form of a time sequence of at least two individual laser pulses, wherein the transmitted laser beam illuminates a detection area limited to a portion of the observation area with each individual laser pulse. • Generate (1003) a scanning motion of the transmitted and received laser beams in the scanning direction, the scanning motion causing progressive sampling of the entire observation area in multiple successive detection regions in the scanning direction. • A received laser beam generated by reflection and / or scattering of the transmitted laser beam on an object in the observation area is received (1004) on a detection surface, the detection surface having a row or matrix arrangement of multiple sub-detectors arranged side-by-side in a first extending direction, wherein the detection area currently detected by the transmitted laser beam is imaged on the detection surface as image points. The method is characterized by comprising the following additional steps: • Select a specific angular range of the observation area (1005), wherein the angular range (307) is capable of defining the detection area (310). n ), • A first single laser pulse groups (1006) sub-detectors into a first macropixel, the first single laser pulse illuminating a first detection region, wherein the grouped sub-detectors of the first macropixel image a selected angular range and are detected by an image point currently imaged on the detection surface at a first time point; and wherein the signals of the grouped sub-detectors are collectively assigned to a histogram belonging to the first macropixel; and • For at least one second single laser pulse, sub-detectors are grouped (1007) into at least one second macropixel, the second single laser pulse illuminating at least one second detection region, wherein the grouped sub-detectors of the at least one second macropixel image a selected angular range and are detected by an image point currently imaged on the detection surface at at least one second time point, and wherein the signals of the grouped sub-detectors are collectively assigned to a second histogram belonging to the at least one second macropixel; and • Analysis and processing (1008) of the first macropixel and the at least one second macropixel, used to determine distance information of the selected angle range based on the propagation time of the corresponding single laser pulse. The number of sub-detectors used to group the first macropixel at the first time point is different from the number of sub-detectors used to group the at least one second macropixel at the at least one second time point. • In this way, the sub-detectors are divided into at least one second macro-pixel independently of the first macro-pixel, so that the histograms associated with the at least one second macro-pixel (160-1) are created and analyzed independently of the histograms associated with the first macro-pixel (160-1). n Histogram of ).

3. A computer program product configured to perform all the steps of the method (1000) according to claim 2.

4. A machine-readable storage medium on which a computer program product according to claim 3 is stored.

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