Multiple beam generation from a single source beam for use with a lidar system
Embodiments discussed herein refer to generating multiple laser beams from a single beam source. Single source multi-beam splitters can produce multiple beams from a single source, precisely control the exit angle of each beam, and ensure that each beam has substantially the same intensity.
1. An optical splitter for use with a light detection and ranging (LiDAR) system, comprising:
a first portion of the optical splitter, wherein the first portion of the optical splitter includes a region in which an input light beam interacts with the optical splitter at an angle of incidence (AOI);
a first planar surface; and
a second planar surface that is unparallel to the first planar surface, the first planer surface and the second planar surface forming a wedge angle; and
one or more beam intensity equalizing portions disposed on one of the first planar surface or the second planar surface,
wherein the optical splitter emits a plurality of output beams that are derived from the input light beam via the first planar surface, the second planar surface, and the one or more beam intensity equalizing portions, wherein the wedge angle is configured such that each of the plurality of output beams is directed at a respective output angle and wherein one or more optical characteristics of the one or more beam intensity equalizing portions are configured such that at least two of the plurality of output beams have substantially similar beam intensities.
2. The optical splitter of claim 1 , wherein the wedge angle formed between the first planer surface and the second planar surface is configured based on one or more of the AOI, a diameter of the input light beam, an inter-beam angle requirement, and an inter-beam spacing requirement.
3. The optical splitter of claim 1 , further comprising optics configured to control divergence of the plurality output beams.
4. The optical splitter of claim 1 , wherein the first planar surface and the second planar surface are surfaces of an optical prism structure.
5. The optical splitter of claim 4 , wherein the optical prism structure is a trapezoidal prism.
6. The optical splitter of claim 1 , wherein the wedge angle is configured such that inter-beam angles of adjacent output beams of the plurality of output beams are the same.
7. The optical splitter of claim 1 , where the first portion of the optical splitter and the one or more beam intensity equalizing portions are disposed on the first planar surface.
8. The optical splitter of claim 1 , wherein the second planar surface comprises a completely reflective material.
9. The optical splitter of claim 1 , wherein at least some of the one or more beam intensity equalizing portions comprise a partially reflective material.
10. The optical splitter of claim 1 , wherein the one or more beam intensity equalizing portions comprise plurality of beam intensity equalizing portions having different reflectivity and transmissivity ratios.
11. The optical splitter of claim 1 , further comprising a chamfer edge.
12. The optical splitter of claim 1 , wherein the one or more beam intensity equalizing portions comprise a continuously variable medium that changes in thickness as a position along one of the first planar surface or the second planar surface.
13. The optical splitter of claim 1 , wherein the first portion of the optical is disposed on the first planar surface and wherein the one or more beam intensity equalizing portions are disposed on the second planar surface.
14. A light detection and ranging (LiDAR) system, comprising:
an optical scanner comprising on or more optics; and
a laser subsystem comprising a laser source and an optical splitter that produces a plurality of output beams that are steered by the optical scanner in accordance with a field of view (FOV), wherein the optical splitter comprises:
a first portion of the optical splitter, wherein the first portion of the optical splitter includes a region in which an input light beam intreacts with the optical splitter at an angle of incidence (AOI);
a first planar surface; and
a second planar surface that is unparallel to the first planar surface, the first planer surface and the second planar surface forming a wedge angle; and
one or more beam intensity equalizing portions disposed on one of the first planar surface or the second planar surface,
wherein the optical splitter emits a plurality of output beams that are derived from the input light beam via the first planar surface, the second planar surface, and the one or more beam intensity equalizing portions, wherein the wedge angle is configured such that each of the plurality of output beams is directed at a respective output angle and wherein one or more optical characteristics of the one or more beam intensity equalizing portions are configured such that at least two of the plurality of output beams have substantially similar beam intensities.
15. The LiDAR system of claim 14 , wherein the optical scanner comprises:
a polygon structure; and
a mirror optically coupled to the polygon structure.
16. The LiDAR system of claim 15 , wherein the mirror is configured to receive the plurality of output beams and direct the output beams to the polygon structure.
17. The LiDAR system of claim 14 , wherein the optical splitter comprises a prism structure.
18. The LiDAR system of claim 14 , further comprising optics configured to control divergence of one or more of the plurality output beams.
19. The LiDAR system of claim 14 , wherein the one or more beam intensity equalizing portions comprise plurality of beam intensity equalizing portions having different reflectivity and transmissivity ratios.