阅读说明：本技术 混合lidar接收器和lidar方法 (Hybrid LIDAR receiver and LIDAR method ) 是由 B·基里洛夫 于 2019-05-15 设计创作，主要内容包括：一种LIDAR系统,包括：接收器,包括光电检测器阵列,光电检测器阵列被配置为检测光并基于检测到的光生成电信号；以及空间光调制器,具有包括多个列的阵列反射元件。每个列包括被配置为可切换地引导光朝向光电检测器阵列的多个反射元件,其中空间光调制器被配置为接收来自视场中的对象的、与从该对象反射的环境光相对应的光。LIDAR系统包括：控制器,被配置为顺序地激活空间光调制器的多个列,使得被激活列的多个反射元件引导光朝向光电检测器阵列；以及至少一个处理器,被配置为接收来自光电检测器阵列的电信号,并且生成表示视场的环境光图片的二维图像。(A LIDAR system, comprising: a receiver comprising an array of photodetectors configured to detect light and generate an electrical signal based on the detected light; and a spatial light modulator having an array of reflective elements comprising a plurality of columns. Each column includes a plurality of reflective elements configured to switchably direct light toward a photodetector array, wherein the spatial light modulator is configured to receive light from an object in the field of view corresponding to ambient light reflected from the object. The LIDAR system includes: a controller configured to sequentially activate the plurality of columns of the spatial light modulator such that the plurality of reflective elements of the activated columns direct light towards the photodetector array; and at least one processor configured to receive the electrical signals from the photodetector array and generate a two-dimensional image representing an ambient light picture of the field of view.)

1. a light detection and ranging (LIDAR) system, comprising:

A receiver, the receiver comprising:

A photodetector array configured to detect light and generate an electrical signal based on the detected light; and

A spatial light modulator having an array of modulator elements comprising a plurality of columns and a plurality of rows, each of the modulator elements configured to switchably direct light toward and away from the photodetector array, wherein the spatial light modulator is configured to receive light from an object in a field of view corresponding to ambient light reflected from the object;

A controller configured to sequentially activate segments of the spatial light modulator such that activated modulator elements in the activated segments direct the light towards the photodetector array; and

At least one processor configured to receive the electrical signals from the photodetector array and generate a two-dimensional image representing an ambient light image of the field of view.

2. The LIDAR system of claim 1, further comprising:

A laser irradiation device configured to emit pulsed light,

wherein the controller is configured to control the laser irradiation apparatus to emit the pulsed light to the object in the field of view during a first scanning mode of operation, and the controller is configured to control the laser irradiation apparatus during a second mode of operation such that the pulsed light is not emitted to the object in the field of view,

wherein the controller is configured to sequentially activate the segments of the spatial light modulator during the second mode of operation, and

wherein the at least one processor is configured to receive the electrical signals from the photodetector array during the second mode of operation and generate the two-dimensional image representative of the ambient light image of the field of view.

3. the LIDAR system of claim 2, wherein the at least one processor is configured to receive the electrical signals from the photodetector array during the first scanning mode of operation, and to generate a three-dimensional image of the field of view, wherein the at least one processor is further configured to match pixel information of the two-dimensional image to pixel information of the three-dimensional image.

4. the LIDAR system of claim 1, wherein the photodetector array is an avalanche photodiode array.

5. The LIDAR system of claim 1, wherein the controller is configured to sequentially activate the plurality of columns of the spatial light modulator as activated portions on an individual basis such that remaining columns of the plurality of columns are deactivated.

6. the LIDAR system of claim 1, wherein:

The controller is configured to sequentially activate the plurality of columns of the spatial light modulator as activated portions on an individual basis from a first column of the spatial light modulator to a second column of the spatial light modulator.

7. The LIDAR system of claim 1, wherein:

Each column of the plurality of columns corresponds to a different receive direction from the field of view, an

the at least one processor is configured to separately record the environmental image data from each different receive direction based on the scanning of the plurality of columns and to generate the two-dimensional image based on the recorded environmental image data from each different receive direction.

8. the LIDAR system of claim 1, wherein:

The at least one processor is configured to: calibrating the spatial light modulator by determining a receive angle of light for each of the plurality of columns based on pixel values derived from the electrical signals and by mapping each column to a particular receive angle.

9. a method of scanning a field of view implemented by a light detection and ranging (LIDAR) system, the method comprising:

Receiving light beams from the field of view on a spatial light modulator comprising a two-dimensional array of modulator elements arranged in a plurality of rows and a plurality of columns, wherein each received light beam extends along one of the plurality of columns;

determining a first set of spatially separated columns of the plurality of columns, the first set of spatially separated columns of the plurality of columns corresponding to receive directions of a first set of receive light beams corresponding to a first scanning process; and

during the first scanning process, at least partially activating each column of the first set of spatially separated columns such that each received light beam of the first set of received light beams is directed toward a photodetector array while deactivating remaining columns of the plurality of columns during the first scanning process such that light is not received at the photodetector array.

10. The method of claim 9, further comprising:

A pattern that shifts activated columns of the spatial light modulator, comprising:

Determining a second set of spatially separated columns of the plurality of columns, the second set of spatially separated columns of the plurality of columns corresponding to receive directions of a second set of receive light beams corresponding to a second scanning process;

during the second scanning process, at least partially activating each column of the second set of spatially separated columns such that each received light beam of the second set of received light beams is directed toward the photodetector array while deactivating remaining columns of the plurality of columns during the second scanning process such that light is not received at the photodetector array, wherein the first set of spatially separated columns is different from the second set of spatially separated columns.

11. The method of claim 10, wherein the first set of spatially separated columns is offset from the second set of spatially separated columns by a fixed number of columns.

12. The method of claim 10, wherein each column of the first set of spatially separated columns is separated by a first number of deactivated columns during the first scanning process, and wherein each column of the second set of spatially separated columns is separated by a second number of deactivated columns during the second scanning process.

13. the method of claim 12, wherein the first and second numbers of deactivated columns are equal.

14. the method of claim 10, wherein each column in the second set of spatially-separated columns is a neighboring column with respect to one column in the first set of spatially-separated columns.

15. The method of claim 9, wherein activating the first set of spatially-separated columns comprises:

Simultaneously activating a first set of the spatially separated columns for the first scanning process.

16. The method of claim 9, wherein activating the first set of spatially-separated columns comprises:

Sequentially activating the first set of spatially separated columns during the first scanning process such that activating each column of the first set of spatially separated columns is synchronized with a reception time of a corresponding one of the first set of reception light beams.

17. The method of claim 9, wherein the modulator elements in each of the plurality of columns are arranged in groups, wherein modulator elements of one group are configured to direct light toward the same pixels of the photodetector array when activated, and the modulator elements of a different group in the same column are configured to direct light toward different pixels of the photodetector array when activated.

18. The method of claim 17, further comprising:

activating the modulator elements in each group of the first set of spatially separated columns in an interleaved manner for different scan periods of the first scanning process.

19. The method of claim 17, wherein the first scanning process comprises a first scan of the field of view and a second scan of the field of view, the method further comprising:

performing the first scan during which the first reflective elements in each group of the first set of spatially separated columns are activated and the second reflective elements in each group of the first set of spatially separated columns are deactivated; and is

Performing the second scan during which the second reflective elements in each group of the first set of spatially separated columns are activated and the first reflective elements in each group of the first set of spatially separated columns are deactivated.

20. the method of claim 9, further comprising:

Launching the light beam into the field of view from a transfer mirror oscillating about a single scan axis such that the light beam is projected into the field of view as a vertical scan line that moves horizontally across the field of view as the transfer mirror oscillates about the single scan axis.

21. A method of scanning a field of view implemented by a light detection and ranging (LIDAR) system, the method comprising:

Receiving light beams from the field of view on a spatial light modulator comprising a two-dimensional array of modulator elements arranged in a plurality of rows and a plurality of columns, wherein each light beam extends along one of the plurality of columns and different light beams received along different columns correspond to different directions of reception of the different light beams;

Wherein the modulator elements in each of the plurality of columns are arranged in groups such that the modulator elements of one group are configured to direct light toward the same pixels of a photodetector array when activated, and the modulator elements of a different group in the same column are configured to direct light toward different pixels of the photodetector array when activated;

The modulator elements in each group are activated in a staggered manner for different scan periods.

22. The method of claim 21, further comprising:

selecting a set of columns of the plurality of columns corresponding to the receive directions of the different beams; and

The modulator elements in each group of the selected set of columns are activated alternately for different scan periods, while the remaining reflective elements in columns not comprised by the selected set of columns of the spatial light modulator are deactivated during the different scan periods.

23. the method of claim 21, further comprising:

emitting the light beam into the field of view from a transfer mirror that oscillates about a single scan axis such that the light beam is projected into the field of view as a vertical scan line that moves horizontally across the field of view as the transfer mirror oscillates about the single scan axis,

Wherein during a first scan the respective first modulator element of each group in a first column of the plurality of columns is activated while the light beam is received from a first horizontal position, wherein the first horizontal position corresponds to the first column,

Wherein other modulator elements in each group of the first column are deactivated during the first scan,

Wherein during a second scan, a respective second modulator element in each group of the first column is activated while a light beam is received from the first horizontal position, an

Wherein during the second scan, other modulator elements in each group of the first column are deactivated.

Technical Field

The present disclosure relates generally to devices and methods for light detection and ranging (LIDAR).

background

Light detection and ranging (LIDAR) is a remote sensing method that uses light in the form of pulsed laser light to measure distance (variable distance) to one or more objects in the field of view. In particular, light is emitted towards the object. An array of photodetectors receives reflections from an object illuminated by light and determines the time required for the reflections to reach each sensor in the photodetector array. This is also known as measuring time of flight (TOF). LIDAR systems form and perform depth measurements by mapping distances to objects based on time-of-flight calculations. Thus, time-of-flight calculations can create distance and depth maps that can be used to generate images.

however, ambient light may also be received at the LIDAR receiver and may contribute to the light-generated signals used to generate the distance and depth maps. Such ambient light may have the undesirable effect of missing objects, detecting ghost objects, or creating noise in the distance and depth maps. It is therefore desirable to develop a LIDAR system that is robust to noise caused by ambient light.

furthermore, when using a one-dimensional (1D) photodetector array at the receiver, the vertical resolution of the image is limited by the number of pixels of the photodetector array that are aligned in the vertical direction. It is therefore desirable to develop a LIDAR system that increases the vertical resolution of the 1D photodetector array.

Disclosure of Invention

drawings

embodiments are described herein with reference to the accompanying drawings.

fig. 1A is a schematic diagram of a LIDAR scanning system in accordance with one or more embodiments;

Fig. 1B is another schematic diagram of a LIDAR scanning system in accordance with one or more embodiments;

fig. 1C is a schematic diagram illustrating components of a receiver of a LIDAR scanning system in accordance with one or more embodiments;

Fig. 2 is a schematic diagram illustrating components of a receiver of a LIDAR scanning system in accordance with one or more embodiments;

Fig. 3 is a cross-sectional view of a receiver of a LIDAR scanning system in accordance with one or more embodiments;

Fig. 4 is a cross-sectional view of a receiver of a LIDAR scanning system in accordance with one or more embodiments;

Fig. 5 is a schematic diagram illustrating components of a receiver of a LIDAR scanning system in accordance with one or more embodiments;

Fig. 6 is a schematic diagram of a LIDAR scanning system in one or more modes of operation in accordance with one or more embodiments;

Fig. 7 is a schematic diagram of a LIDAR scanning system in one or more modes of operation in accordance with one or more embodiments;

Fig. 8 is a schematic diagram of a LIDAR scanning system in one or more modes of operation in accordance with one or more embodiments; and

fig. 9 is a schematic diagram of a LIDAR scanning system in one or more modes of operation in accordance with one or more embodiments.

Embodiments provide a light detection and ranging (LIDAR) system and a LIDAR scanning method.

in accordance with one or more embodiments, a LIDAR system includes: a receiver comprising an array of photodetectors configured to detect light and generate an electrical signal based on the detected light; and a spatial light modulator having an array of reflective elements, the array comprising a plurality of columns, each column of the plurality of columns comprising a plurality of reflective elements configured to switchably direct light towards the photodetector array, wherein the spatial light modulator is configured to receive light from an object in the field of view corresponding to ambient light reflected from the object. The LIDAR system further comprises: a controller configured to sequentially activate the plurality of columns of the spatial light modulator such that the plurality of reflective elements of the activated columns direct light toward the photodetector array; and at least one processor configured to receive the electrical signals from the photodetector array and generate a two-dimensional image representing an ambient light image of the field of view. Each pixel of the ambient light image indicates a light intensity of ambient light corresponding to the pixel.

In accordance with one or more embodiments, a method of scanning a field of view implemented by a LIDAR system is provided. The method comprises the following steps: receiving light beams from a field of view on a spatial light modulator, the spatial light modulator comprising a two-dimensional array of reflective elements arranged in a plurality of rows and a plurality of columns, wherein each light beam extends along one of the plurality of columns; determining a first set of spatially separated columns of the plurality of columns, the first set of spatially separated columns of the plurality of columns corresponding to receive directions of a first set of receive light beams corresponding to a first scanning process; and activating the first set of spatially separated columns during a first scanning process such that each received light beam of the first set of received light beams is directed toward the photodetector array while deactivating remaining columns of the plurality of columns during the first scanning process such that light is directed away from the photodetector array.

In accordance with one or more embodiments, a method of scanning a field of view implemented by a LIDAR system is provided. The method comprises the following steps: receiving light beams from a field of view on a spatial light modulator, the spatial light modulator comprising a two-dimensional array of reflective elements arranged in a plurality of rows and a plurality of columns, wherein each light beam extends along one of the plurality of columns; arranging the reflective elements in each of the plurality of columns into a group, wherein the reflective elements of one group are configured to direct light toward the same pixels of the photodetector array when activated, and different groups of reflective elements in the same column are configured to direct light toward different pixels of the photodetector array when activated; selecting a set of columns of the plurality of columns corresponding to a direction of reception of the light beam; and for different scan periods, interleaving activation of reflective elements in each group of the selected set of columns while deactivating remaining reflective elements of the spatial light modulator during the different scan periods.