[go: up one dir, main page]

AU7215791A - Optical scanning device - Google Patents

Optical scanning device

Info

Publication number
AU7215791A
AU7215791A AU72157/91A AU7215791A AU7215791A AU 7215791 A AU7215791 A AU 7215791A AU 72157/91 A AU72157/91 A AU 72157/91A AU 7215791 A AU7215791 A AU 7215791A AU 7215791 A AU7215791 A AU 7215791A
Authority
AU
Australia
Prior art keywords
objective lens
motion
lens
cylindrical lens
mutually perpendicular
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
AU72157/91A
Inventor
Christian Buchler
Yasuaki Morimoto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Deutsche Thomson Brandt GmbH
Original Assignee
Deutsche Thomson Brandt GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Deutsche Thomson Brandt GmbH filed Critical Deutsche Thomson Brandt GmbH
Publication of AU7215791A publication Critical patent/AU7215791A/en
Abandoned legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
    • G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
    • G11B7/0908—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for focusing only
    • G11B7/0909—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for focusing only by astigmatic methods
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
    • G11B7/135—Means for guiding the beam from the source to the record carrier or from the record carrier to the detector
    • G11B7/1365—Separate or integrated refractive elements, e.g. wave plates
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
    • G11B7/135—Means for guiding the beam from the source to the record carrier or from the record carrier to the detector
    • G11B7/1372—Lenses
    • G11B7/1378—Separate aberration correction lenses; Cylindrical lenses to generate astigmatism; Beam expanders

Landscapes

  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Optical Head (AREA)
  • Optical Recording Or Reproduction (AREA)
  • Vehicle Body Suspensions (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)
  • Optical Communication System (AREA)
  • Electrochromic Elements, Electrophoresis, Or Variable Reflection Or Absorption Elements (AREA)
  • Microscoopes, Condenser (AREA)
  • Holo Graphy (AREA)

Abstract

In an optical scanning device, a light beam (L) is focused astigmatically by an objective lens (O) on a record carrier, e.g. a disk (CD), which reflects it onto a four-quadrant photodetector (PD). The astigmatism is produced by an astigmatic element, e.g., a concave or convex cylindrical lens (ZX) or two mutually perpendicular transparent disks located in the beam path. The light beam (L) can be moved radially by a coarse drive. The objective lens (O) can also be moved radially by a fine drive in a direction (W) which makes an angle $g(a) to the normals (R) to the data tracks (S). However, the movement of the objective lens (O) controlled by the fine drive through the angle $g(a) causes imaging defects on the four-quadrant photodector (A, B, C, D), which lead to faulty focusing. To prevent faulty focusing due to imaging defects, a preferred axis of the astigmatic element, e.g., a cylindrical lens or two mutually perpendicular transparent disks, runs parallel to the direction of movement (W) of the objective lens. In the case of a convex cylindrical lens (ZX), the longitudinal axis (LA) is parallel to the direction of motion (W) of the objective lens. In the case of a concave cylindrical lens, the transverse axis is parallel to the direction of motion (W) of the objective lens. In the case of two mutually perpendicular transparent disks, the straight line SG which intersects the two disks is perpendicular to the direction of motion (W) of the objective lens. CD players, video disk players, DRAW disk players, and magneto-optical devices.
AU72157/91A 1990-02-16 1991-02-06 Optical scanning device Abandoned AU7215791A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4004858A DE4004858A1 (en) 1990-02-16 1990-02-16 OPTICAL SCANNER
DE4004858 1990-02-16

Publications (1)

Publication Number Publication Date
AU7215791A true AU7215791A (en) 1991-09-03

Family

ID=6400308

Family Applications (1)

Application Number Title Priority Date Filing Date
AU72157/91A Abandoned AU7215791A (en) 1990-02-16 1991-02-06 Optical scanning device

Country Status (11)

Country Link
EP (1) EP0515422B1 (en)
JP (1) JP2930137B2 (en)
CN (1) CN1023920C (en)
AT (1) ATE110875T1 (en)
AU (1) AU7215791A (en)
DE (2) DE4004858A1 (en)
ES (1) ES2063491T3 (en)
FI (1) FI923636A0 (en)
HK (1) HK113395A (en)
HU (1) HUT62419A (en)
WO (1) WO1991012609A1 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3191200B2 (en) * 1994-11-10 2001-07-23 コニカ株式会社 Recording / reproducing device for optical information recording medium
US5675686A (en) * 1995-07-05 1997-10-07 W. L. Gore & Associates, Inc. Buffer material for optical signal transmission media
JP2001034999A (en) * 1999-05-14 2001-02-09 Fujitsu Ltd Optical information storage device and optical element
CN101049720B (en) * 2006-04-05 2010-09-01 鸿富锦精密工业（深圳）有限公司 Sensor for alignment of mould core, sensing method, and mould composition of possessing the sensor for alignment
CN107064563B (en) * 2017-03-29 2020-06-23 中国科学院苏州纳米技术与纳米仿生研究所 Light path damping device and method based on scanning probe

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6038771B2 (en) * 1978-06-19 1985-09-03 パイオニア株式会社 Servo device for optical information reading device
JPS5971141A (en) * 1982-10-14 1984-04-21 Mitsubishi Electric Corp Optical signal readout device
JPH01130332A (en) * 1987-11-17 1989-05-23 Toshiba Corp Focal point control device

Also Published As

Publication number Publication date
DE59102748D1 (en) 1994-10-06
FI923636A (en) 1992-08-14
HUT62419A (en) 1993-04-28
CN1023920C (en) 1994-03-02
DE4004858A1 (en) 1991-08-22
CN1054848A (en) 1991-09-25
ATE110875T1 (en) 1994-09-15
HK113395A (en) 1995-07-21
ES2063491T3 (en) 1995-01-01
EP0515422B1 (en) 1994-08-31
EP0515422A1 (en) 1992-12-02
JP2930137B2 (en) 1999-08-03
JPH05504224A (en) 1993-07-01
FI923636A0 (en) 1992-08-14
WO1991012609A1 (en) 1991-08-22

Similar Documents

Publication Publication Date Title
KR100388515B1 (en) Optical pickup apparatus
EP0055646B1 (en) Device for optically accessing a track on a movable information carrier
US6114689A (en) Optical pickup device
EP0326354A3 (en) Apparatus for reading information out of an optical recording medium
JP2633535B2 (en) Optical pickup device
US5412634A (en) Optical scanning device for a disc player including improved focusing apparatus
KR19980064228A (en) Optical disc recording and reproducing apparatus and method
JPS5766533A (en) Optical information reader
AU7215791A (en) Optical scanning device
US6434104B2 (en) Objective lens, optical pickup device and optical disk device
JPH0434740A (en) Optical head
EP0400570A3 (en) Optical information processing system
KR910700520A (en) Optical pickup
EP0367465A3 (en) Optical pickup devices
JP3692729B2 (en) Optical disk device
US4868821A (en) Optical pickup which includes a single objective lens having magnification equal to or greater than 3 and equal to or smaller than 5
JPS63140426A (en) Optical pick-up device
JP3766524B2 (en) Optical system for optical information recording / reproducing head
JPH0261831A (en) Optical head
JPS58147821A (en) Optical head
JPS60187941A (en) Optical information detector
JPS573236A (en) Optical information reader
JPS6478442A (en) Optical pickup device
JPS60234242A (en) Optical head
JPH11142774A (en) Galvano-mirror