LIDAR system
A light detection and ranging (LIDAR) system includes a laser source and a polygon scanner. The laser source is configured to generate a first beam. The polygon scanner includes a frame and a plurality of mirrors coupled to the frame, each mirror comprising a glass material.
1. A light detection and ranging (LIDAR) system, comprising:
a laser source configured to generate a beam; and
a polygon scanner, comprising:
a frame having a first flat frame surface and a second flat frame surface around an axis, and at least one frame portion between the first frame surface and the second frame surface; and
a plurality of mirrors coupled to the frame, each mirror comprising a glass material, a central portion of an inner surface of a first mirror of the plurality of mirrors coupled to the first frame surface and a central portion of an inner surface of a second mirror of the plurality of mirrors coupled to the second frame surface, the at least one frame portion is spaced from the inner surface of the first mirror and curves from the first frame surface, the central portion of the first mirror is coupled to the first frame surface by an adhesive, the adhesive having a coefficient of thermal expansion about equal to a coefficient of thermal expansion of the first mirror, the first mirror extending further than the first frame surface in a direction along the axis, wherein the first mirror has a first edge adjacent to a second edge of the second mirror and a gap is between the first edge and the second edge.
2. The LIDAR system of claim 1 , wherein each mirror comprises a polished glass material.
3. The LIDAR system of claim 1 , further comprising a modulator configured to receive the beam and modulate at least one of a phase or a frequency of the beam to output a modulated beam to the polygon scanner.
4. The LIDAR system of claim 1 , wherein a distortion of at least one mirror of the plurality of mirrors relative to a plane of the at least one mirror is from 0 nanometers (nm) to less than about 200 nm over a temperature range from about negative 20 degrees Celsius to about 50 degrees Celsius.
5. The LIDAR system of claim 1 , wherein the frame is to rotate about the axis, and the direction is parallel with the axis.
6. The LIDAR system of claim 1 , wherein the first edge is at a distance from the frame.
7. The LIDAR system of claim 1 , wherein the first edge and the second edge are angled such that the gap decreases in size in a direction away from the axis.
8. An autonomous vehicle control system, comprising:
a laser source configured to generate a first beam;
a polygon scanner comprising a frame and a plurality of mirrors coupled to the frame, the frame having a first flat frame surface and a second flat frame surface around an axis, the frame comprising at least one frame portion between the first frame surface and the second frame surface, each mirror comprising a glass material, a central portion of an inner surface of a first mirror of the plurality of mirrors coupled to the first frame surface and a central portion of an inner surface of a second mirror of the plurality of mirrors coupled to the second frame surface, the at least one frame portion is spaced from the inner surface of the first mirror and curves from the first frame surface, the central portion of the first mirror is coupled to the first frame surface by an adhesive, the adhesive having a coefficient of thermal expansion about equal to a coefficient of thermal expansion of the first mirror, the first mirror extending further than the first frame surface in a direction along the axis, the polygon scanner configured to reflect the first beam as a second beam, wherein the first mirror has a first edge adjacent to a second edge of the second mirror and a gap is between the first edge and the second edge; and
one or more processors configured to:
determine at least one of a range to an object or a velocity of the object using a third beam received from at least one of reflection or scattering of the second beam by the object; and
control operation of an autonomous vehicle responsive to the at least one of the range or the velocity.
9. The autonomous vehicle control system of claim 8 , further comprising a motor configured to rotate the polygon scanner.
10. The autonomous vehicle control system of claim 8 , wherein the one or more processors are configured to determine the range to the object based on a time of flight associated with the second beam and the third beam.
11. The autonomous vehicle control system of claim 8 , wherein each mirror comprises a polished glass material.
12. The autonomous vehicle control system of claim 8 , further comprising a modulator configured to receive the beam and modulate at least one of a phase or a frequency of the beam to output a modulated beam to the polygon scanner.
13. The autonomous vehicle control system of claim 8 , wherein the first mirror is made from a material such that a distortion of the first mirror relative to a plane of the first mirror is from 0 nanometers (nm) to less than about 200 nm over a temperature range from about negative twenty degrees Celsius to about 50 degrees Celsius.
14. The autonomous vehicle control system of claim 8 , wherein the frame surface is a first frame surface, and the frame comprises a second frame surface and at least one portion between the first frame surface and the second frame surface, the at least one portion spaced from the inner surface.
15. An autonomous vehicle, comprising: a LIDAR system, comprising: a laser source configured to generate a first beam; and a polygon scanner comprising a frame and a plurality of mirrors coupled to the frame, the frame having a first flat frame surface around an axis and a second flat frame surface around the axis, the frame comprising at least one frame portion between the first frame surface and the second frame surface, each mirror comprising a glass material, a central portion of an inner surface of a first mirror of the plurality of mirrors coupled to the first frame surface and a central portion of a second mirror of the plurality of mirrors coupled to the second frame surface, the at least one frame portion is spaced from the inner surface of the first mirror and curves from the first frame surface, the central portion of the first mirror is coupled to the first frame surface by an adhesive, the adhesive having a coefficient of thermal expansion about equal to a coefficient of thermal expansion of the first mirror, the first mirror extending further than the first frame surface in a direction along the axis, the polygon scanner configured to reflect the first beam to output a second beam, wherein the first mirror has a first edge adjacent to a second edge of the second mirror and a gap is between the first edge and the second edge; a steering system; a braking system; and a vehicle controller comprising one or more processors configured to: determine at least one of a range to an object or a velocity of the object using a third beam received from at least one of reflection or scattering of the second beam by the object; and control operation of the at least one of the steering system and the braking system responsive to the at least one of the range or the velocity.