# US 10,768,346 B2 · Optical beam steering devices having polygonal reflectors therein > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,768,346 B2 - Document ID: US10768346B2 - Status: Granted - Kind: B2 - Application number: 16/191,984 - Filed: 2018-11-15 - Published: 2019-04-04 - Granted: 2020-09-08 - Earliest claimed: 2017-02-24 - Assignees: Mirada Technologies Inc. - Applicants: Mirada Technologies Inc. - Inventors: Andrew Carl Miner; Jonathan King Mapel - Web page: https://patentgrep.com/patent/US10768346B2 ## CPC - G02B 5/09: Multifaceted or polygonal mirrors {, e.g. polygonal scanning mirrors; Fresnel mirrors} - F16C 17/00: Sliding-contact bearings for exclusively rotary movement (F16C32/06 takes precedence; adjustable bearings F16C23/00, F16C25/00) - G02B 1/06: made of fluids in transparent cells - G02B 26/121: {Mechanical drive devices for polygonal mirrors} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS ## Abstract An optical beam steering device includes an at least partially optically transparent container having a polygonal reflector therein that is at least partially surrounded within the container by an optically transparent liquid. The polygonal reflector may be configured to have a center of mass, which is equivalent to its geometric center. In addition, the polygonal reflector may be configured so that a difference between an effective density of the polygonal reflector and a density of the optically transparent liquid is preferably less than about 2.1 grams per cubic centimeter. More preferably, the polygonal reflector and the optically transparent liquid may be collectively configured to be neutrally buoyant relative to each other within the container. ## Claims ### Claim 1 An optical beam steering device, comprising: an at least partially optically transparent container having a polygonal reflector therein that is surrounded on all sides thereof by an optically transparent liquid; and wherein the polygonal reflector and the optically transparent liquid are collectively configured to be neutrally buoyant relative to each other within the container. ### Claim 2 (depends on 1) The device of claim 1, wherein a center of mass of the polygonal reflector is located at the geometric center of the polygonal reflector. ### Claim 3 (depends on 1) The device of claim 1, wherein the polygonal reflector is annular-shaped; and wherein the container comprises a hub extending through an opening in the annular-shaped polygonal reflector, which is filled with the optically transparent liquid. ### Claim 4 (depends on 3) The device of claim 3, wherein the optically transparent liquid within the opening operates as a liquid bearing when said annular-shaped polygonal reflector rotated about the hub. ### Claim 5 (depends on 1) The device of claim 1, further comprising a motor in the container, which is mechanically coupled to the polygonal reflector. ### Claim 6 (depends on 5) The device of claim 5, wherein the motor is mechanically coupled to the polygonal reflector by a shaft. ### Claim 7 (depends on 5) The device of claim 5, wherein the container is partially filled by the optically transparent liquid and partially filled by a gas; and wherein the container is configured as a pressure-compensated structure having a gas containing region therein that is remote relative to the polygonal reflector and the motor, which are fully submerged within the optically transparent liquid. ### Claim 8 (depends on 1) The device of claim 1, wherein a difference between an effective density of the polygonal reflector and a density of the optically transparent liquid is less than about 2.1 grams per cubic centimeter. ### Claim 9 (depends on 1) The device of claim 1, wherein the optically transparent liquid is a Fluorinert liquid. ### Claim 10 (depends on 8) The device of claim 8, wherein the difference between the effective density of the polygonal reflector and the density of the optically transparent liquid is less than about 1 gram per cubic centimeter. ### Claim 11 (depends on 8) The device of claim 8, wherein the difference between the effective density of the polygonal reflector and the density of the optically transparent liquid is less than about 0.5 grams per cubic centimeter. ### Claim 12 An optical beam steering device, comprising: an at least partially optically transparent container having a polygonal reflector therein that is at least partially surrounded within the container by an optically transparent liquid; and wherein the polygonal reflector and the optically transparent liquid are collectively configured to yield a substantially neutrally buoyant condition within the container. ### Claim 13 (depends on 12) The device of claim 12, wherein the polygonal reflector is configured to have an effective density within ±30% of an effective density of the optically transparent liquid. ### Claim 14 (depends on 12) The device of claim 12, wherein the polygonal reflector is configured to have an effective density within ±20% of an effective density of the optically transparent liquid. ### Claim 15 (depends on 1) The device of claim 1, wherein the polygonal reflector is configured to have an effective density within ±10% of an effective density of the optically transparent liquid. ### Claim 16 (depends on 1) The device of claim 1, further comprising: a motor in the container; and a shaft that mechanically couples the polygonal reflector to the electric motor so that optically reflective surfaces on an exterior of the polygonal reflector are rotated in front of at least one optically transparent window within the container, in response to motor-controlled rotation of the shaft within the optically transparent liquid. ### Claim 17 (depends on 16) The device of claim 16, wherein the shaft and polygonal reflector have an average density matched to a density of the optically transparent liquid. ### Claim 18 An optical beam steering device for light detection and ranging (LiDAR), comprising: a sealed container having at least one optically transparent window therein; a motor in the container; an optically transparent fluid at least partially filling the container; and a polygonal reflector surrounded on all sides thereof by the optically transparent fluid and mechanically coupled by a shaft to the motor, said motor, shaft and polygonal reflector collectively configured so that optically reflective surfaces on an exterior of the polygonal reflector are rotated in front of the at least one optically transparent window, in response to motor-controlled rotation of the shaft within the optically transparent fluid; and wherein the polygonal reflector, shaft and optically transparent fluid are collectively configured to yield a substantially neutrally buoyant condition within the container. ### Claim 19 (depends on 18) The device of claim 18, wherein the polygonal reflector is configured to have an effective density within ±30% of an effective density of the optically transparent fluid. ### Claim 20 (depends on 18) The device of claim 18, wherein a difference between an effective density of the polygonal reflector and a density of the optically transparent fluid is less than about 1 gram per cubic centimeter. ### Claim 21 (depends on 3) The device of claim 3, wherein the hub comprises a non-magnetic material. ### Claim 22 (depends on 3) The device of claim 3, wherein the hub comprises an optically transparent plastic. ### Claim 23 (depends on 3) The device of claim 3, wherein the opening in the annular-shaped polygonal reflector is a circular-shaped opening. ### Claim 24 (depends on 23) The device of claim 23, wherein the hub has a circular-shaped outer perimeter. ### Claim 25 (depends on 1) The device of claim 1, wherein the container is partially filled by the optically transparent liquid and partially filled by a gas; and wherein the container is configured as a pressure-compensated structure having a gas containing region therein that is remote relative to the polygonal reflector, which is fully submerged within the optically transparent liquid. ### Claim 26 (depends on 2) The device of claim 2, wherein the container is partially filled by the optically transparent liquid and partially filled by a gas; and wherein the container is configured as a pressure-compensated structure having a gas containing region therein that is remote relative to the polygonal reflector, which is fully submerged within the optically transparent liquid. ### Claim 27 An optical beam steering device for light detection and ranging (LiDAR), comprising: an at least partially optically transparent container having a polygonal reflector therein that is surrounded on all sides thereof by an optically transparent liquid having an effective density within ±30% of an effective density of the polygonal reflector so that a substantially neutrally buoyant condition is present between the polygonal reflector and the optically transparent liquid within the container. ### Claim 28 (depends on 27) The device of claim 27, wherein the optically transparent liquid is a Fluorinert liquid. ### Claim 29 (depends on 12) The device of claim 12, wherein the optically transparent liquid is a Fluorinert liquid. ### Claim 30 (depends on 18) The device of claim 18, wherein the optically transparent fluid comprises Fluorinert.