# US 12,217,108 B2 · Laser marking of machine-readable codes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,217,108 B2 - Document ID: US12217108B2 - Status: Granted - Kind: B2 - Application number: 18/077,914 - Filed: 2022-12-08 - Published: 2023-06-08 - Granted: 2025-02-04 - Earliest claimed: 2020-06-12 - Assignees: Digimarc Corporation - Applicants: Digimarc Corporation - Inventors: Tomas Filler; Vojtech Holub; Hugh L. Brunk; Adnan M. Alattar - Web page: https://patentgrep.com/patent/US12217108B2 ## CPC - B41J 2/442: {using lasers} - G06K 19/06037: {multi-dimensional coding} - B23K 26/0823: {Devices involving rotation of the workpiece} - B23K 26/355: {Texturing} - B23K 26/361: for deburring or mechanical trimming (B23K26/351 takes precedence) - B23K 26/362: Laser etching - B41J 3/40733: {Printing on cylindrical or rotationally symmetrical objects, e. g. on bottles} - G06K 1/126: {by photographic or thermographic registration (recording apparatus for measuring instruments G01D15/00)} - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS - G06K: GRAPHICAL DATA READING (image or video recognition or understanding G06V); PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS - B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM ## Abstract A surface is laser-etched to convey a 2D machine-readable code pattern. Various strategies are detailed to minimize the etching time. Some strategies include modifying the code pattern to reduce a path length traveled by the laser. Some strategies include modifying the code pattern to make it sub-optimal, i.e., making the code pattern a less-faithful approximation of an ideal code pattern. In some embodiments the etched surface is the surface of a plastic container, and the code pattern conveys information indicating the type of plastic of which the container is manufactured. A variety of other features and arrangements are also detailed. ## Claims ### Claim 1 A system for marking a workpiece, the system comprising first and second laser emitters and a controller, the controller being configured by control instructions to direct laser illumination from said laser emitters to locations on the workpiece at which marks are to be formed, wherein said control instructions configure the laser emitters to turn on and off independently of each other, yet the marks formed by the first and second laser emitters cooperate to form an area of 2D machine-readable coding from which a plural symbol payload is extractable by a compliant decoder. ### Claim 2 (depends on 1) The system of claim 1 including a rotary turntable for receiving a generally-cylindrical workpiece, and a drive arrangement that moves the laser emitters in a first direction parallel to an axis of the turntable, said controller being configured to jointly operate said turntable and said drive arrangement to direct the laser illumination from said laser emitters to locations on the cylindrical workpiece at which said marks are to be formed. ### Claim 3 (depends on 1) The system of claim 1 including a drive arrangement that moves the emitters in one direction, and a mirror arrangement that effects redirection of the laser illumination in a second, orthogonal direction. ### Claim 4 (depends on 3) The system of claim 3 in which there are two mirror arrangements, one for each laser emitter, that are configured by said instructions for independent redirection. ### Claim 5 (depends on 4) The system of claim 4 in which said instructions configure the mirror arrangement for each laser emitter to direct a laser beam to a sequence of locations based on proximity of marks, and not based on a raster pattern. ### Claim 6 (depends on 3) The system of claim 3 in which the drive arrangement moves the emitters in a vertical direction, and the mirror arrangement effects a raster redirection of the laser illumination in a horizontal direction. ### Claim 7 (depends on 1) The system of claim 1 in which the controller is configured to cause the first and second laser emitters to simultaneously mark spaced-apart first and second locations on the workpiece at a first time, and to cause the first but not the second laser emitter to mark a third location on the workpiece at a second time, and to cause the second but not the first laser emitter to mark a fourth location on the workpiece at a third time. ### Claim 8 (depends on 1) The system of claim 1 in which the first laser emitter is nominally directed in a first direction, and the second laser emitter is nominally directed in a second direction, wherein the first and second directions are non-parallel. ### Claim 9 A process of marking a plastic container with 2D code information, the process including the acts: generating two or more laser beams, the beams being identically modulated in intensity over time; and steering the beams simultaneously to sequences of different locations on the container, to thereby laser-etch identical spaced-apart patterns on the container, said patterns comprising said 2D code information; wherein the container is marked with redundant 2D code information patterns. ### Claim 10 (depends on 9) The process of claim 9 that includes rotating the plastic container continuously during said marking. ### Claim 11 (depends on 9) The process of claim 9 that includes rotating the plastic container step-wise during said marking. ### Claim 12 (depends on 9) The process of claim 9 in which the 2D code information includes plural identical 2D blocks of marks, disposed edge-to-edge. ### Claim 13 (depends on 9) The process of claim 9 in which the plastic container is a cylindrical bottle, and the process includes marking a majority of a cylindrical surface of the bottle with the 2D code information. ### Claim 14 (depends on 9) The process of claim 9 in which the plastic container is a cylindrical bottle having a circumference, and the 2D code information comprises a signal block sized to be an integral fraction of the bottle circumference, so that an integer number of signal blocks spans the bottle circumference. ### Claim 15 An apparatus for marking a plastic container with 2D code information, the apparatus comprising: means for generating two or more laser beams, the beams being identically modulated in intensity over time; and means for steering the beams simultaneously to sequences of different locations on the container, to thereby laser-etch identical spaced-apart patterns on the container, said patterns comprising said 2D code information; whereby the container is marked with redundant 2D code information patterns. ### Claim 16 (depends on 15) The apparatus of claim 15 that includes means for rotating the plastic container continuously during marking with redundant 2D code information patterns. ### Claim 17 (depends on 15) The apparatus of claim 15 that includes means for rotating the plastic container step-wise during marking with redundant 2D code information patterns. ### Claim 18 (depends on 15) The apparatus of claim 15 in which the 2D code information includes plural identical 2D blocks of marks, disposed edge-to-edge. ### Claim 19 (depends on 15) The apparatus of claim 15 in which the plastic container is a cylindrical bottle, and in which said means for steering steers the beams to mark a majority of a cylindrical surface of the bottle with the 2D code information. ### Claim 20 (depends on 15) The apparatus of claim 15 in which the plastic container is a cylindrical bottle having a circumference, and the 2D code information comprises a signal block sized to be an integral fraction of the bottle circumference, so that an integer number of signal blocks spans the bottle circumference.