Multiple pixel scanning LIDAR
Methods and systems for performing three-dimensional (3-D) LIDAR measurements with multiple illumination beams scanned over a 3-D environment are described herein. In one aspect, illumination light from each LIDAR measurement channel is emitted to the surrounding environment in a different direction by a beam scanning device. The beam scanning device also directs each amount of return measurement light onto a corresponding photodetector. In some embodiments, a beam scanning device includes a scanning mirror rotated in an oscillatory manner about an axis of rotation by an actuator in accordance with command signals generated by a master controller. In some embodiments, the light source and photodetector associated with each LIDAR measurement channel are moved in two dimensions relative to beam shaping optics employed to collimate light emitted from the light source. The relative motion causes the illumination beams to sweep over a range of the 3-D environment under measurement.
1. A method for manufacturing a light detection and ranging (LIDAR) device, the method comprising:
mounting a plurality of illumination sources on a substrate, each of the plurality of illumination sources configured to emit illumination light;
mounting a plurality of photosensitive detectors on the substrate, each of the plurality of photosensitive detectors configured to detect an amount of return light;
mounting an overmold lens over a photosensitive detector of the plurality of photosensitive detectors, the overmold lens including a conical cavity that corresponds with a ray acceptance cone of the return light; and
arranging a beam scanning device in an optical path of the plurality of illumination sources, the beam scanning device configured to redirect the illumination light with respect to each of the plurality of illumination sources, when in use.
2. The method of claim 1 , further comprising:
arranging a beam shaping optical element in an optical path between the plurality of illumination sources and the beam scanning device.
3. The method of claim 1 , further comprising:
communicatively coupling the plurality of illumination sources to a computing system, the computing system configured to generate signals that cause the plurality of illumination sources to emit the illumination light.
4. The method of claim 1 , further comprising:
communicatively coupling the plurality of photosensitive detectors to a computing system, the computing system configured to receive signals indicative of the amount of return light from the plurality of photosensitive detectors.
5. The method of claim 4 , further comprising:
configuring the computing system to determine a distance between the LIDAR device and an object in a three-dimensional environment based on the received signals.
6. The method of claim 1 , further comprising:
coupling an actuator to an optical element of the beam scanning device.
7. The method of claim 6 , further comprising:
communicatively coupling the actuator to a computing system, the computing system configured to generate signals that cause the actuator to move the optical element of the beam scanning device.
8. The method of claim 6 , wherein the optical element is a mirror.
9. The method of claim 8 , wherein the actuator is configured to rotate the mirror about an axis of rotation.
10. The method of claim 9 , wherein the actuator is configured to rotate the mirror about the axis of rotation with an oscillatory angular velocity.
11. The method of claim 9 , wherein the plurality of illumination sources are disposed in a plane substantially parallel to the axis of rotation.
12. The method of claim 9 , wherein the plurality of illumination sources are disposed in a plane substantially perpendicular to the axis of rotation.
13. The method of claim 1 , further comprising:
coupling a first actuator to a beam shaping optical element of the beam scanning device, the first actuator configured to translate the beam shaping optical element in a first direction substantially parallel to an optical plane of the beam shaping optical element;
coupling a second actuator to the substrate, the second actuator configured to translate the substrate in a second direction substantially parallel to the optical plane of the beam shaping optical element, the first direction different than the second direction.
14. The method of claim 1 , wherein the substrate is a printed circuit board that provides mechanical support and electrical connectivity for the plurality of illumination sources and the plurality of photosensitive detectors.
15. A method of claim 1 , wherein the plurality of illumination sources are arranged as a two-dimensional array of illumination sources.
16. A method for manufacturing a light detection and ranging (LIDAR) device, the method comprising:
arranging a plurality of integrated LIDAR measurement devices in an array, each of the plurality of integrated LIDAR measurement devices including an illumination source configured to emit illumination light and a photosensitive detector configured to detect an amount of return light;
arranging a beam scanning device in an optical path of the plurality of integrated LIDAR measurement devices, the beam scanning device configured to redirect the illumination light and return light with respect to the plurality of integrated LIDAR measurement devices;
mounting an overmold lens over the photosensitive detector, the overmold lens including a conical cavity that corresponds with a ray acceptance cone of the return light; and
communicatively coupling the plurality of integrated LIDAR measurement devices and the beam scanning device to a computing system.
17. The method of claim 16 , further comprising:
arranging a beam shaping optical element in an optical path between the plurality of integrated LIDAR measurement devices and the beam scanning device.
18. The method of claim 16 , further comprising:
manufacturing each of the plurality of integrated LIDAR measurement devices, wherein manufacturing each of the plurality integrated LIDAR measurement devices includes:
mounting the illumination source to a substrate; and
mounting the photosensitive detector to the substrate.
19. The method of claim 18 , wherein the substrate is a printed circuit board that provides mechanical support and electrical connectivity for the illumination source and the photosensitive detector.
20. The method of claim 18 , wherein manufacturing each of the plurality integrated LIDAR measurement devices further includes:
mounting an illumination driver integrated circuit to the substrate;
mounting a return signal receiver integrated circuit to the substrate;
communicatively coupling the illumination driver integrated circuit to the illumination source and to the return signal receiver integrated circuit; and
communicatively coupling the return signal receiver integrated circuit to the photosensitive detector.
21. The method of claim 16 , wherein manufacturing each of the plurality integrated LIDAR measurement devices further includes:
mounting a waveguide to the substrate; and
optically coupling the illumination source to the waveguide such that the illumination light is injected into the ray acceptance cone of the return light, when in use.
22. The method of claim 16 , further comprising:
configuring the computing system to:
transmit a first set of signals to each of the plurality of integrated LIDAR measurement devices, the first set of signals configured to cause the illumination sources of each of the plurality of integrated LIDAR measurement devices to emit the illumination light;
receive a second set of signals from each of the plurality of integrated LIDAR measurement devices, the second set of signals indicative of the amount of return light detected at the photosensitive detectors of each of the plurality of integrated LIDAR measurement devices; and
determine a distance between the LIDAR device and an object in a three-dimensional environment based on the second set of signals.
23. The method of claim 16 , further comprising:
manufacturing the beam scanning device by dynamically coupling an actuator to an optical element;
wherein communicatively coupling the beam scanning device to the computing system includes communicatively coupling the actuator to the computing system.
24. The method of claim 23 , further comprising:
configuring the computing system to output a signal configured to cause the actuator to move the optical element of the beam scanning device.
25. The method of claim 23 , wherein the optical element is a mirror.
26. The method of claim 25 , wherein the actuator is configured to rotate the mirror about an axis of rotation.
27. The method of claim 26 , wherein the actuator is configured to rotate the mirror about the axis of rotation with an oscillatory angular velocity.
28. The method of claim 26 , wherein the plurality of integrated LIDAR measurement devices are disposed in a plane substantially parallel to the axis of rotation.
29. The method of claim 26 , wherein the plurality of integrated LIDAR measurement devices are disposed in a plane substantially perpendicular to the axis of rotation.
30. The method of claim 16 , further comprising:
manufacturing the beam scanning device by dynamically coupling a first actuator to a beam shaping optical element, the first actuator configured to translate the beam shaping optical element in a first direction substantially parallel to an optical plane of the beam shaping optical element;
dynamically coupling a second actuator to the plurality of integrated LIDAR measurement devices, the second actuator configured to translate the plurality of integrated LIDAR measurement devices in a second direction substantially parallel to the optical plane of the beam shaping optical element, the first direction different than the second direction.
31. The method of claim 16 , wherein the plurality of integrated LIDAR measurement devices are arranged as a two-dimensional array.