# US 6,297,923 B1 · Disk-cartridge detection system incorporating an angled light emitter/detector > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,297,923 B1 - Document ID: US6297923B1 - Status: Granted - Kind: B1 - Application number: 09/191,877 - Filed: 1998-11-13 - Granted: 2001-10-02 - Earliest claimed: 1998-11-13 - Assignees: Iomega Corporation - Inventors: Michael C. Burnside; Dale E. Lee - Web page: https://patentgrep.com/patent/US6297923B1 ## CPC - G11B 23/30: with provision for auxiliary signals - G11B 23/0302: {Auxiliary features} - G11B 23/031: {Indicating means, e.g. sticker, bar code} - G11B 23/0313: {Container cases} - G11B 23/042: {Auxiliary features (sensing such features G11B15/06)} - G11B 23/046: {Indicating means, e.g. quantity of tape} - 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) ## Abstract A disk drive has an improved ability to detect the presence of a disk cartridge inserted into the drive. The improved disk drive comprises a source of irradiance and a detector of irradiance. When a disk cartridge is inserted into the drive, the detector is optically connected to the source of irradiance by a reflective marker on the cartridge. The emitting surface of the source is oriented such that the irradiance strikes the reflective marker at an angle substantially less than 90 degrees. The detector surface which receives the reflected irradiance is oriented in a manner similar to the emitting surface. This detection system exploits the relatively unique characteristic of certain reflective markers to reflect light in a direction opposite the incident path when the angle of incidence with the reflecting surface is substantially less than 90 degrees. ## Claims ### Claim 1 A data-storage system comprising: (a) a disk drive of the type that receives a removable data-storage cartridge, comprising: (1) a source of irradiance disposed within said disk drive, said source of irradiance comprising an emitting surface, said emitting surface being disposed in a first plane within said disk drive; and (2) a detector of irradiance disposed within said disk drive, said detector of irradiance comprising a receiving surface, said receiving surface being disposed in a second plane within said disk drive; and (b) said removable data-storage cartridge, said cartridge comprising an exterior surface and a retro-reflective marker comprising a plurality of reflective panels said reflective panels being disposed in planes that form a pitch angle with a back surface of said marker, said reflective marker being disposed along said exterior surface of said cartridge, said exterior surface of said cartridge being disposed in a third plane within said disk drive when said cartridge is inserted in said disk drive, said third plane being disposed at acute angles with said first plane and said second plane and said angle between said first plane and said third plane being about equal to said pitch angle of said reflective panels, said reflective marker being in optical communication with said source of irradiance and said detector when said cartridge is inserted in said disk drive. ### Claim 2 (depends on 1) The data-storage system of claim 1, wherein said angle between said second plane and said third plane is about equal to said pitch angle of said reflective panels. ### Claim 3 (depends on 2) The data-storage system of claim 2, wherein said pitch angle is about 30 degrees. ### Claim 4 (depends on 1) The data-storage system of claim 1, wherein said pitch angle is about 30 degrees. ### Claim 5 (depends on 1) The data-storage system of claim 1, wherein a distance between said reflective marker and said emitting surface is about 10 mm. ### Claim 6 (depends on 1) The data-storage system of claim 1, wherein a distance between said reflective marker and said receiving surface is about 10 mm. ### Claim 7 (depends on 1) The data-storage system of claim 1, wherein said disk drive farther comprises a circuit board on which said source of irradiance and said detector are disposed. ### Claim 8 (depends on 1) The data-storage system of claim 1, wherein said disk drive further comprises a housing that encloses said source of irradiance and said detector. ### Claim 9 (depends on 1) The data-storage system of claim 1, wherein said source of irradiance further comprises a light-emitting diode. ### Claim 10 (depends on 1) The data-storage system of claim 1, wherein said disk drive further comprises read/write heads for interfacing with said data-storage cartridge. ### Claim 11 (depends on 10) The data-storage system of claim 10, wherein said disk drive further comprises an electrical circuit that controls the operation of said read/write heads. ### Claim 12 (depends on 1) The data-storage system of claim 1, wherein said source of irradiance further comprises a light-emitting diode. ### Claim 13 (depends on 1) The data-storage system of claim 1, wherein said disk drive further comprises an actuator. ### Claim 14 (depends on 13) The data-storage system of claim 13, wherein said disk drive further comprises an electrical circuit, said electrical circuit being responsive to said detector to enable said actuator when said detector senses light reflected from said reflective marker above a predetermined level. ### Claim 15 A disk drive of the type that receives a removable data-storage cartridge, said data-storage cartridge comprising an external surface and a retro-reflective marker, said external surface being disposed in a first plane within said disk drive when said cartridge is inserted in said disk drive, said marker comprising a plurality of reflective panels being disposed at a pitch angle in relation to a back surface of said marker, said disk drive comprising: a source of irradiance comprising an emitting surface, said emitting surface being disposed in a second plane within said disk drive, said second plane forming an angle with said first plane that is about equal to said pitch angle; and a detector of irradiance being in selective optical communication with said source of irradiance and comprising a receiving surface, said receiving surface being disposed in a third plane within said disk drive, said third plane forming an angle with said first plane that is about equal to said pitch angle. ### Claim 16 A data-storage system comprising: (a) a disk drive of the type that receives a removable data-storage cartridge, comprising: (1) a source of irradiance disposed within said disk drive, said source of irradiance comprising an emitting surface, said emitting surface being disposed in a first plane within said disk drive; and (2) a detector of irradiance disposed within said disk drive, said detector of irradiance comprising a receiving surface, said receiving surface being disposed in a second plane within said disk drive; and (b) said removable data-storage cartridge, said cartridge comprising an exterior surface and a retro-reflective marker comprising a plurality of reflective panels, said reflective panels being disposed in planes that form a pitch angle with a back surface of said marker, said reflective marker being disposed along said exterior surface of said cartridge, said exterior surface of said cartridge being disposed in a third plane within said disk drive when said cartridge is inserted in said disk drive, said third plane being disposed at acute angles with said first plane and said second plane and said angle between said second plane and said third plane being about equal to said pitch angle of said reflective panels, said reflective marker being in optical communication with said source of irradiance and said detector when said cartridge is inserted in said disk drive.