Lidar sensor system with small form factor
A sensor system can comprise a light source generating a light pulse that is collimated, and a plurality of optical elements. Each of the plurality of optical elements is configured to rotate independently about an axis that is substantially common, and the plurality of optical elements operate to collectively direct the light pulse to one or more objects in an angle of view of the sensor system. Furthermore, the sensor system can comprise a detector configured to receive, via the plurality of optical elements, at least a portion of photon energy of the light pulse that is reflected back from the one or more objects in the angle of view of the sensor system, and convert the received photon energy into at least one electrical signal.
1. A sensor system, comprising:
an emitting structure that comprises:
a light source configured to generate a light pulse that is collimated in a first optical path, and
a reflective surface positioned to receive the light pulse from the light source and direct the light pulse in a second, different optical path;
a plurality of optical elements positioned in an optical aperture to allow the light pulse from the reflective surface to pass through the optical aperture via the plurality of optical elements, wherein individual optical elements are configured to rotate independently about a substantially common axis that corresponds to the second optical path, and wherein the plurality of optical elements is operable to collectively direct the light pulse to one or more objects in an angle of view of a sensor system; and
a detector configured to
receive, via the plurality of optical elements, at least a portion of photon energy of the light pulse that is reflected back from the one or more objects in the angle of view of the sensor system, wherein the reflective surface is positioned at a distance from a center of the optical aperture to reduce blocking the light pulse that is reflected back from the one or more objects; and
convert the received photon energy into at least one electrical signal.
2. The sensor system of claim 1 , wherein at least one of said plurality of optical elements is a prism, a grating, a mirror or an optical phased array.
3. The sensor system of claim 2 , wherein the plurality of optical elements is configured to direct the light pulse to at least two different directions via rotating.
4. The sensor system of claim 3 , wherein at least two optical elements of the plurality of optical elements are configured to rotate at different angular speeds.
5. The sensor system of claim 3 , wherein at least two optical elements of the plurality of optical elements are configured to start rotation from different initial positions.
6. The sensor system of claim 1 , further comprising:
a beam splitter arranged between the light source and the plurality of optical elements, wherein the beam splitter is configured to direct the light pulse toward the plurality of optical elements; and
direct the photon energy of the light pulse that is reflected back from the one or more objects toward the detector.
7. The sensor system of claim 6 , further comprising:
a baffle tube that is configured to extend a light exit on the beam splitter to prevent scattered light of the light source from interfering with the detector.
8. The sensor system of claim 6 , wherein at least one optical element of the plurality of optical elements is tilted to reduce reflection of incoming light from the light source into the detector.
9. The sensor system of claim 1 ,
wherein the reflective surface comprises a mirror.
10. The sensor system of claim 1 , wherein the emitting structure is configured to have a narrow profile that matches a beam profile of the light pulse.
11. The sensor system of claim 1 , wherein each said optical element is applied with a coating that reduces reflection.
12. The sensor system of claim 1 , further comprising a band-pass filter that matches a wavelength of the light pulse.
13. The sensor system of claim 1 , wherein a receiving device for the detector is configured with a profile that matches a beam profile of the light pulse.
14. The sensor system of claim 1 , further comprising a spatial filtering apparatus that prevents scattered or reflected light from reaching the detector, wherein the spatial filtering apparatus comprises at least one pinhole or slit that matches a beam profile of the light pulse.
15. The sensor system of claim 13 , further comprising a field stop aperture that is arranged in front of the detector.
16. The sensor system of claim 1 , wherein the light pulse is emitted with an instantaneous intensity at least comparable with sunlight intensity.
17. The sensor system of claim 1 , wherein the sensor system is enclosed in a housing with an emission window.
18. A method for sensing objects in an angle of view, comprising:
generating, by a light source, a light pulse that is collimated in a first optical path;
directing, by a reflective surface, the light pulse in the first optical path to a second optical path toward a plurality of optical elements positioned in an optical aperture such that the light pulse passes through the optical aperture via the plurality of optical elements, wherein individual optical elements are independently rotatable about a substantially common axis that corresponds to the second optical path, and wherein the plurality of optical elements is operable to collectively direct the light pulse to one or more objects in the angle of view;
receiving, via the plurality of optical elements, at least a portion of photon energy of the light pulse that is reflected back from the one or more objects in the angle of view, wherein the reflective surface is positioned at a distance from a center of the optical aperture to reduce blocking the light pulse that is reflected back from the one or more objects; and
converting the received photon energy into at least one electrical signal.
19. A sensor system, comprising:
an emitting structure that comprises a light source configured to generate a light pulse that is collimated in a first optical path, and
a mirror positioned to receive the light pulse from the light source and direct the light pulse in a second, different optical path;
one or more prisms positioned in an optical aperture to allow the light pulse from the mirror to pass through the optical aperture via the one or more prisms, wherein individual prisms are configured to rotate independently about a substantially common axis that corresponds to the second optical path, and wherein the one or more prisms are operable to collectively direct the light pulse to one or more objects in an angle of view of the sensor system; and
a detector configured to:
receive, via the one or more prisms, at least a portion of photon energy of the light pulse that is reflected back from the one or more objects in the angle of view of the sensor system, wherein the mirror is positioned at a distance from a center of the optical aperture to reduce blocking the light pulse that is reflected back from the one or more objects; and
convert the received photon energy into at least one electrical signal.
20. The method of claim 18 , wherein the plurality of optical elements includes a first optical element and a second optical element, and wherein the method further comprises rotating the first and second optical elements at different rates.
21. The method of claim 18 , wherein the plurality of optical elements includes a first prism and a second prism.
22. The method of claim 18 , wherein the plurality of optical elements includes a first optical element and a second optical element, and wherein the method further comprises rotating the first and second optical elements to produce a spiral pulse distribution in the angle of view.
23. The method of claim 18 , wherein the plurality of optical elements includes a first optical element and a second optical element, and wherein the method further comprises rotating the first and second optical elements to produce a spiral pulse distribution in a form of a Lissajous figure.
24. The method of claim 18 , further comprising filtering a portion of photon energy.
25. The method of claim 18 , further comprising forming a light beam from multiple light pulses, the light beam having a non-circular cross-section.
26. The sensor system of claim 19 , further comprising a land vehicle, and wherein the land vehicle carries the emitting structure, the one or more prisms, and the detector.
27. The sensor system of claim 19 , further comprising a beam splitter between the light source and the detector.
28. The sensor system of claim 19 , wherein no beam splitter is positioned between the light source and the detector.
29. The sensor system of claim 19 , wherein the light source, the one or more prisms, and the detector form a first unit, and wherein the sensor system further comprises at least a second unit, the second unit including a second light source and additional one or more prisms configured to rotate independently about a second common axis, and a second detector, the first and second units facing in different directions.
30. The sensor system of claim 1 , further comprising a vehicle, and wherein the vehicle carries the emitting structure, the plurality of optical elements, and the detector.