# US 5,353,299 A · Gas laser > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,353,299 A - Document ID: US5353299A - Status: Granted - Kind: A - Application number: 07/948,023 - Filed: 1992-09-21 - Granted: 1994-10-04 - Earliest claimed: 1990-03-21 - Assignees: Rofin-Sinar Laser GmbH - Inventors: Hinrich Martinen; Hermann Hage - Web page: https://patentgrep.com/patent/US5353299A ## CPC - H01S 3/0818: {Unstable resonators} - H01S 3/0315: {Waveguide lasers} - H01S 3/038: Electrodes, e.g. special shape, configuration or composition - H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL ## Abstract An electrically excited gas laser includes coaxial hollow-cylindrical electrodes defining a discharge space between the electrodes. A resonator mirror is disposed at each respective end of the discharge space. At least one of the resonator mirrors forms an intersection line with a cylindrical surface being coaxial with the electrodes and the intersection line extends obliquely relative to the circumferential direction. The resonator mirrors form intersection lines with an axial plane of the electrodes and the intersection lines extend substantially at right angles to the axis. At least one of the resonator mirrors extends over only a portion of the circumference of the discharge space. ## Claims ### Claim 1 An electrically excited gas laser, comprising: a) coaxial hollow-cylindrical electrodes defining a discharge space between said electrodes and ends of said discharge space; b) two resonator mirrors each being disposed at a respective one of said ends of said discharge space; c) at least one of said resonator mirrors forming an intersection line with a cylindrical surface defined coaxially between said electrodes, said intersection line extending obliquely offset from the circumferential direction; d) said resonator mirrors forming intersection lines with an axial plane of said electrodes, said intersection lines extending substantially at right angles to the axis; and e) at least one of said resonator mirrors extending over only a portion of the circumference of said discharge space. ### Claim 2 (depends on 1) The gas laser according to claim 1, wherein said intersection lines formed by one of said resonator mirrors with the cylindrical surfaces have a step and extend generally obliquely relative to the circumferential direction on both sides of said step. ### Claim 3 (depends on 2) The gas laser according to claim 2, wherein said intersection lines formed by one of said resonator mirrors with the cylindrical surfaces extend on both sides of the step with a curvature oriented toward said discharge space and center points of the curvature being offset in the circumferential direction. ### Claim 4 (depends on 2) The gas laser according to claim 2, wherein said intersection lines formed by one of said resonator mirrors with the cylindrical surfaces on both sides of the step extend with a curvature oriented away from said discharge space and center points of the curvature being offset in the circumferential direction. ### Claim 5 (depends on 1) The gas laser according to claim 1, wherein said intersection lines formed by one of said resonator mirrors with the cylindrical surfaces have a curvature oriented away from said discharge space and center points of the curvature being offset in the circumferential direction. ### Claim 6 (depends on 1) The gas laser according to claim 1, wherein said intersection lines formed by one of said resonator mirrors with the cylindrical surfaces have a curvature oriented toward said discharge space and center points of the curvature being offset in the circumferential direction. ### Claim 7 (depends on 1) The gas laser according to claim 1, wherein said electrodes have axial planes, and at least one of said resonator mirrors forms intersection lines being straight and at right angles to the axis. ### Claim 8 (depends on 1) The gas laser according to claim 1, wherein said electrodes have axial planes, and one of said resonator mirrors forms intersection lines with a curvature oriented toward said discharge space and center points of the curvature being disposed in the middle of said discharge space between said electrodes facing one another. ### Claim 9 (depends on 8) The gas laser according to claim 8, wherein the other of said resonator mirrors forms intersection lines with a curvature oriented toward said discharge space and center points of the curvature being disposed in the middle of said discharge space between said electrodes facing one another. ### Claim 10 (depends on 1) The gas laser according to claim 1, wherein said discharge space has a thickness of less than 1 cm. ### Claim 11 (depends on 1) The gas laser according to claim 1, wherein said outer electrode has an inside diameter of at least 3 cm. ### Claim 12 (depends on 1) The gas laser according to claim 1, wherein said electrodes have a length of at least 10 cm. ### Claim 13 (depends on 1) The gas laser according to claim 1, wherein said electrodes have surfaces facing toward said discharge space and reflective dielectric coatings on said surfaces. ### Claim 14 (depends on 1) The gas laser according to claim 1, wherein said electrodes have conduits for a coolant. ### Claim 15 (depends on 1) The gas laser according to claim 1, including an exit location for a laser beam, and an axial optical system at said exit location. ### Claim 16 An electrically excited gas laser, comprising: a) coaxial hollow-cylindrical electrodes defining a discharge space between said electrodes and ends of said discharge space; b) two resonator mirrors each disposed at a respective one of said ends of said discharge space; c) at least one of said resonator mirrors forming an intersection line with a cylindrical surface defined coaxially between said electrodes, said intersection line defining a plane, and a normal of said plane extending non-parallel with respect to a cylinder axis of said cylindrical surface; d) said resonator mirrors forming intersection lines with an axial plane of said electrodes, said intersection lines extending substantially at right angles to the axis; and e) at least one of said resonator mirrors extending over only a portion of the circumference of said discharge space.