# US 7,613,099 B2 · Solid immersion lens, condensing lens, optical pickup device, optical recording and reproducing apparatus and method of forming solid immersion lens > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,613,099 B2 - Document ID: US7613099B2 - Status: Granted - Kind: B2 - Application number: 11/073,608 - Filed: 2005-03-08 - Published: 2005-10-20 - Granted: 2009-11-03 - Earliest claimed: 2004-03-15 - Assignees: Sony Corporation - Inventors: Masataka Shinoda - Web page: https://patentgrep.com/patent/US7613099B2 ## CPC - G11B 7/1374: Objective lenses {(optical objectives per se G02B9/00)} - G02B 19/0014: {at least one surface having optical power} - G02B 19/0047: {for use with a light source (G02B19/009, G02B19/0095 take precedence; details of lighting devices in general F21V; non-semiconductor lasers having optical devices external to the laser cavity H01S3/005)} - G02B 19/0085: {for use with both a detector and a source (, e.g. in a transceiver, G02B19/009, G02B19/0095 take precedence)} - G02B 21/33: Immersion oils {, or microscope systems or objectives for use with immersion fluids} - G11B 7/1378: Separate aberration correction lenses; Cylindrical lenses to generate astigmatism; Beam expanders - G11B 7/1387: using the near-field effect - G11B 7/22: Apparatus or processes for the manufacture of optical heads, e.g. assembly - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract A solid immersion lens has an inclined portion formed on at least a part thereof from the tip end portion of the objective side to a spherical portion and an inclination angle θ is expressed as θ≧θi where θi represents the angle of incidence of light incident on the solid immersion lens. There are provided a solid immersion lens capable of increasing a tilt margin between a lens and an optical recording medium and so on and which can decrease a diameter of a lens and a method for forming a solid immersion lens. ## Claims ### Claim 1 A solid immersion lens, comprising: an inclined portion formed on at least a part of a tip end portion of the objective side, and having a convex portion formed on its tip end portion so as to protrude toward the objective side, wherein an inclination angle θ from the optical axis of said inclined portion is expressed as: θ≧θi where θi represents an angle of incidence of incident light; and said convex portion is shaped so as to satisfy the following relationships expressed as: tan−1(h/y)<90°−θi tan−1((d+h)/z))≧0.10° tan−1(d/y)≧0.10° where h represents the height protruding toward the objective side, y represents the length from said optical axis to the edge portion of said convex-like portion, z represents the length from said optical axis to the edge portion of the objective side of said inclined portion and d represents a space between said solid immersion lens and the objective. ### Claim 2 (depends on 1) A solid immersion lens according to claim 1, wherein said solid immersion lens has a spherical portion shaped like a hemisphere on the opposite side of the objective side and the tip end face of said convex portion is shaped so as to approximately circumscribe a sphere having a diameter of nearly r where r represents the radius of curvature of said spherical portion. ### Claim 3 (depends on 1) A solid immersion lens according to claim 1, wherein said solid immersion lens has a spherical portion shaped like a hemisphere on the opposite side of the objective side and the tip end face of said convex portion is shaped so as to approximately circumscribe a sphere having a diameter of nearly r where r represents the radius of curvature of said spherical portion. ### Claim 4 (depends on 1) A solid immersion lens according to claim 1, wherein said solid immersion lens has a spherical portion shaped like a hemisphere on the opposite side of the objective side and the tip end face of said convex portion is shaped so as to approximately circumscribe a sphere having a diameter of nearly r where r represents the radius of curvature of said spherical portion. ### Claim 5 (depends on 1) A solid immersion lens according to claim 1, wherein said solid immersion lens has a spherical portion shaped like a hyper-hemisphere on the opposite side of the objective side and the tip end face of said tip end portion is shaped so as to approximately circumscribe a sphere having a radius of nearly r/n where r represents the radius of curvature of said spherical portion and n represents the refractive index. ### Claim 6 (depends on 1) A solid immersion lens according to claim 1, wherein said solid immersion lens has a spherical portion shaped like a hyper-hemisphere on the opposite side of the objective side and the tip end face of said tip end portion is shaped so as to approximately circumscribe a sphere having a radius of nearly r/n where r represents the radius of curvature of said spherical portion and n represents the refractive index. ### Claim 7 (depends on 1) A solid immersion lens according to claim 1, wherein said solid immersion lens has a spherical portion shaped like a hyper-hemisphere on the opposite side of the objective side and the tip end face of said tip end portion is shaped so as to approximately circumscribe a sphere having a radius of nearly r/n where r represents the radius of curvature of said spherical portion and n represents the refractive index. ### Claim 8 A condensing lens, comprising: a solid immersion lens; and an optical lens with its optical axis coincident with that of said solid immersion lens and which is located on the opposite of an objective side, wherein said solid immersion lens has an inclined portion formed on at least a part of a tip end portion of its objective side and an inclination angle θ from the optical axis of said inclined portion is expressed as: θ≧θi where θi represents the angle of incidence of light incident on said solid immersion lens; and said inclined portion has a convex portion formed on its tip end portion so as to protrude toward the objective side, and said convex portion is shaped so as to satisfy the following relationships expressed as: tan−1(h/y)<90°−θi tan−1((d+h)/z))≧0.10° tan−1(d/y)≧0.10° where h represents the height protruding toward the objective side, y represents the length from said optical axis to the edge portion of said convex-like portion, z represents the length from said optical axis to the edge portion of the objective side of said inclined portion and d represents a space between said solid immersion lens and the objective. ### Claim 9 (depends on 8) A condensing lens according to claim 8, wherein said inclined portion of said solid immersion lens has a convex portion formed on its tip end portion so as protrude toward the objective side. ### Claim 10 An optical pickup device, comprising: at least a solid immersion lens; an optical lens with its optical axis coincident with that of said solid immersion lens and which is located on the opposite side of the objective side; a light source; and a condensing lens composed of said solid immersion lens and said optical lens, said condensing lens converging light emitted from said light source to form a light spot, wherein said solid immersion lens has an inclined portion formed at least on a part of a tip end portion of the objective side and an inclination angle θ from the optical axis of said inclined portion is expressed as: θ≧θi where θi represents the angle of incidence of light incident on said solid immersion lens, and said inclined portion has a convex portion formed on its tip end portion so as to protrude toward the objective side, and said convex portion is shaped so as to satisfy the following relationships expressed as: tan−1(h/y)<90°−θi tan−1((d+h)/z))≧0.10° tan−1(d/y)≧0.10° where h represents the height protruding toward the objective side, y represents the length from said optical axis to the edge portion of said convex-like portion, z represents the length from said optical axis to the edge portion of the objective side of said inclined portion and d represents a space between said solid immersion lens and the objective. ### Claim 11 (depends on 10) An optical pickup device according to claim 10, wherein said inclined portion of said solid immersion lens has a convex portion formed at its tip end portion so as to protrude toward the objective side. ### Claim 12 An optical recording and reproducing apparatus, comprising: an optical pickup device including at least a solid immersion lens, an optical lens with its optical axis coincident with that of said solid immersion lens and which is located on the opposite side of the objective side and a condensing lens composed of said solid immersion lens and said optical lens, said converging lens converging light emitted from said light source to form a light spot; and control drive means for moving said condensing lens in the focusing direction and/or tracking direction of an optical recording medium, wherein said solid immersion lens has an inclined portion formed at least on a part of its tip end portion of the objective side and an inclination angle θ from the optical axis of said inclined portion is expressed as: θ≧θi where θi represents the angle of incidence of light incident on said solid immersion lens, and said inclined portion has a convex portion formed on its tip end portion so as to protrude toward the objective side, and said convex portion is shaped so as to satisfy the following relationships expressed as: tan−1(h/y)<90°−θi tan−1((d+h)/z))≧0.10° tan−1(d/y)≧0.10° where h represents the height protruding toward the objective side, y represents the length from said optical axis to the edge portion of said convex-like portion, z represents the length from said optical axis to the edge portion of the objective side of said inclined portion and d represents a space between said solid immersion lens and the objective. ### Claim 13 (depends on 12) An optical recording and reproducing apparatus according to claim 12, wherein said inclined portion of said solid immersion lens has a convex portion formed at its tip end portion so as to protrude toward the objective side. ### Claim 14 A method for forming a solid immersion lens, comprising: at least a process for forming an inclined portion on a lens material; a process for forming a convex portion on the objective side of said lens material; and a process for forming an objective surface of said convex portion, and wherein said convex portion is processed like a shape which can satisfy the following relationships expressed as: tan−1(h/y)<90°−θi tan−1((d+h)/z))≧0.10° tan−1(d/y)≧0.10° where h represents the height protruding toward the objective side, y represents the length from said optical axis to the edge portion of said convex-like portion, z represents the length from said optical axis to the edge portion of the objective side of said inclined portion and d represents a space between said solid immersion lens and the objective. ### Claim 15 (depends on 14) A method for forming a solid immersion lens according to claim 14, wherein said solid immersion lens has a spherical portion shaped as a hemispherical portion on the opposite side of the objective side and said convex portion has a tip end face processed as a shape which nearly circumscribes a sphere having a diameter of nearly r where r represents the radius of curvature of said spherical portion. ### Claim 16 (depends on 14) A method for forming a solid immersion lens according to claim 14, wherein said solid immersion lens has a spherical portion shaped as a hemispherical portion on the opposite side of the objective side and said convex portion has a tip end face processed as a shape which nearly circumscribes a sphere having a diameter of nearly r where r represents the radius of curvature of said spherical portion. ### Claim 17 (depends on 14) A method for forming a solid immersion lens according to claim 14, wherein said solid immersion lens has a spherical portion shaped as a hyper-sphere on the opposite side of the objective side and said convex portion has a tip end portion processed as a shape which nearly circumscribes a sphere having a radius of nearly r/n where r represents the radius of curvature of said spherical portion and n represents the refractive index. ### Claim 18 (depends on 14) A method for forming a solid immersion lens according to claim 14, wherein said solid immersion lens has a spherical portion shaped as a hyper-sphere on the opposite side of the objective side and said convex portion has a tip end portion processed as a shape which nearly circumscribes a sphere having a radius of nearly r/n where r represents the radius of curvature of said spherical portion and n represents the refractive index. ### Claim 19 (depends on 14) A method for forming a solid immersion lens according to claim 14, wherein said tip end portion of said convex portion is processed by a focus ion beam processing method. ### Claim 20 (depends on 14) A method for forming a solid immersion lens according to claim 14, wherein said tip end portion of said convex portion is processed by a focus ion beam processing method. ### Claim 21 (depends on 15) A method for forming a solid immersion lens according to claim 15, wherein said tip end portion of said convex portion is processed by a focus ion beam processing method. ### Claim 22 (depends on 16) A method for forming a solid immersion lens according to claim 16, wherein said tip end portion of said convex portion is processed by a focus ion beam processing method. ### Claim 23 (depends on 17) A method for forming a solid immersion lens according to claim 17, wherein said tip end portion of said convex portion is processed by a focus ion beam processing method. ### Claim 24 (depends on 18) A method for forming a solid immersion lens according to claim 18, wherein said tip end portion of said convex portion is processed by a focus ion beam processing method.