LIDAR WITH POLARIZED WAVEGUIDE
A light detection and ranging system can have a light source coupled to a reflector consisting of a waveguide. The waveguide may be tuned to a selected polarization by a controller to block retroreflected photons resulting from a light beam emitted from the reflector. The waveguide polarization can be altered over time by the controller to provide customized blocking of photons.
1 . An apparatus comprising a light source coupled to a reflector consisting of a waveguide, the waveguide tuned to a selected polarization by a controller to block retroreflected photons and produce a light beam outputted from the reflector.
2 . The apparatus of claim 1 , wherein the light source is positioned on a system on chip with the reflector.
3 . The apparatus of claim 1 , wherein a beam splitter is positioned in the reflector and acts to generate the light beam.
4 . The apparatus of claim 1 , wherein a wave plate is positioned in the reflector and acts to generate the light beam.
5 . The apparatus of claim 1 , wherein a polarizer is positioned in the reflector and acts to generate the light beam.
6 . The apparatus of claim 1 , wherein the waveguide is polarized to a single uniform polarization that corresponds with a selected wavelength of the light beam.
7 . The apparatus of claim 1 , wherein the reflector consists of multiple separate waveguides that are respectively polarized to different wavelengths.
8 . A method comprising:
coupling a light source to a reflector;
activating the light source to generate optical energy; and
selecting, with a controller connected to the reflector, a polarization for the reflector; and
passing the optical energy to the reflector to create a light beam.
9 . The method of claim 8 , wherein the light beam is sensed by the controller to detect a position of a target downrange of the reflector.
10 . The method of claim 8 , wherein the light beam is sensed by the controller to detect a size of a target downrange of the reflector.
11 . The method of claim 8 , wherein the light beam is sensed by the controller to detect a direction of movement of a target downrange of the reflector.
12 . The method of claim 8 , wherein the polarization is selected to balance blocking of retroreflected energy with a strength of the light beam.
13 . The method of claim 8 , wherein the polarization is selected by activating a first waveguide portion of the reflector.
14 . The method of claim 13 , wherein the controller changes to a different polarization for the reflector by activating a second waveguide portion of the reflector.
15 . The method of claim 8 , wherein the controller changes the polarization by applying a different bias voltage to a waveguide portion of the reflector.
16 . The method of claim 8 , wherein the controller selects the polarization of the reflector in response to at least one previously identified target positioned downrange from the reflector.