# US 5,705,799 A · Miniature optical scanning assembly for barcode readers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,705,799 A - Document ID: US5705799A - Status: Granted - Kind: A - Application number: 08/415,337 - Filed: 1996-04-03 - Granted: 1998-01-06 - Earliest claimed: 1990-05-08 - Assignees: Symbol Technologies, Inc. - Inventors: Yajun Li - Web page: https://patentgrep.com/patent/US5705799A ## CPC - G06K 7/10871: {randomly oriented data-fields, code-marks therefore, e.g. concentric circles-code} - G06K 7/10564: {Light sources} - G06K 7/10584: {Source control} - G06K 7/10633: {by oscillation} - G06K 7/10643: {Activating means} - G06K 7/10653: {using flexible or piezoelectric means} - G06K 7/10673: {Parallel lines} - G06K 7/10693: {for omnidirectional scanning} - G06K 7/10811: {Focalisation} - G06K 7/10851: {Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device (basic electronic circuitry H03)} - G06K 7/10881: {constructional details of hand-held scanners} - G06K 7/10891: {the scanner to be worn on a finger or on a wrist} - G06K 7/109: {adaptations to make the hand-held scanner useable as a fixed scanner} - G06K 7/1098: {the scanning arrangement having a modular construction} - G06K 7/1478: {adapting the threshold for pixels in a CMOS or CCD pixel sensor for black and white recognition} - G06K 2007/10534: {Scanner to be worn on a finger or on a wrist} - G06K 2207/1011: Aiming - G06K 2207/1013: Multi-focal - G06K 2207/1016: Motor control or optical moving unit control - G06K 2207/1018: Source control - G06K: GRAPHICAL DATA READING (image or video recognition or understanding G06V); PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS ## Abstract An optical scanning assembly turns an optical element in opposite circumferential directions about a longitudinal axis along which a light beam from a light source is emitted. The optical element and the light source are mounted on individual supports between which torsion elements are connected. An electrical coil arrangement interacts with a permanent magnet to effect the turning movement. ## Claims ### Claim 1 An optical scanning assembly, comprising: a housing; a source within said housing for emitting a light beam along a longitudinal axis to be reflected from a symbol to be scanned; a photodetector positioned within said housing for receiving light reflected from said symbol and responsively producing an electrical signal; an optical element positioned within the housing in a path of said light beam; a permanent magnet mounted to a support member and producing a magnetic field; an electric coil mounted with said optical element and axially displaced from said support member; and a plurality of semi-rigid electrically conducting wires interconnecting said coil and said support member such that AC drive current applied to said coil through said wires causes said coil to generate an electromagnetic field for interaction with the magnetic field of said permanent magnet to produce oscillatory motions of said optical element in opposite circumferential directions about said longitudinal axis. ### Claim 2 (depends on 1) The assembly of claim 1, wherein said semi-rigid wires are made of a phosphor-bronze alloy. ### Claim 3 (depends on 1) The assembly of claim 1, wherein said light source is mounted to said support member on an optical axis of said optical element. ### Claim 4 (depends on 3) The assembly of claim 3, wherein said permanent magnet is in the form of a ring having a central opening aligned with said light source, and serves as an aperture stop for said beam. ### Claim 5 (depends on 4) The assembly of claim 4, wherein said permanent magnet is poled longitudinally. ### Claim 6 (depends on 1) The assembly of claim 1, wherein said optical element comprises a lens. ### Claim 7 (depends on 6) The assembly of claim 6, wherein said permanent magnet is multiply poled circumferentially, and wherein rotation of said ring about said poles controls focus of the beam passing through said lens. ### Claim 8 (depends on 7) The assembly of claim 7, wherein said coil is wired such that current passing therethrough oscillates said lens to describe a prescribed scan pattern and selectively rotates said lens so as to adjust the axial position, and hence, focussing, of said lens. ### Claim 9 An optical scanning assembly, comprising: a) a pair of supports spaced apart along a longitudinal axis; b) a light source on one of the supports for emitting a light beam along the longitudinal axis; c) a permanent magnet on said one support for generating a permanent magnetic field between the supports; d) an optical element on the other of the supports in the path of the light beam, for optically modifying the light beam; and e) a drive for turning at least one of the optical element and the light source in opposite circumferential directions about the longitudinal axis, including an energizeable electrical coil arrangement on said other support for generating an electromagnetic field between the supports for interaction with said permanent magnetic field. ### Claim 10 (depends on 9) The assembly of claim 9, wherein the drive includes a set of semi-rigid, resilient wires extending between the supports along the longitudinal axis, said wires having opposite ends stationarily connected to the supports. ### Claim 11 (depends on 10) The assembly of claim 10, wherein the drive turns the other support and the optical element thereon in a circumferential direction about the longitudinal axis, and twists the wires, to a limited angular extent upon energization of the electrical coil arrangement. ### Claim 12 (depends on 10) The assembly of claim 10, wherein the wires are constituted of an electrically conductive material, and are electrically connected to the electrical coil arrangement for supplying an energizing drive signal thereto. ### Claim 13 (depends on 10) The assembly of claim 10, wherein the electrical coil means includes four coils spaced equi-angularly apart of one another about the longitudinal axis, and wherein the set of wires includes four wires also spaced equi-angularly apart of one another about the longitudinal axis. ### Claim 14 (depends on 10) The assembly of claim 10, wherein the permanent magnet is annular and has a central opening through which the light beam passes. ### Claim 15 (depends on 14) The assembly of claim 14, wherein the central opening is sized to serve as an aperture stop for the light beam. ### Claim 16 (depends on 10) The assembly of claim 10, where the optical element is a focusing lens. ### Claim 17 (depends on 9) The assembly of claim 9, wherein at least one of the supports is a printed circuit board. ### Claim 18 (depends on 9) The assembly of claim 9, wherein said one support has an elongated passage, and wherein said light source is mounted at one end of the passage, and wherein said permanent magnet is mounted at an opposite end of the passage. ### Claim 19 (depends on 18) The assembly of claim 18, wherein said magnet has a central opening in optical alignment with said light source and said permanent magnet. ### Claim 20 (depends on 19) The assembly of claim 19, wherein the drive includes a set of torsion elements extending between the supports in mutual parallelism with one another.