JPS5545122A - Focus controller of optical reader - Google Patents

Focus controller of optical reader

Info

Publication number
JPS5545122A
JPS5545122A JP11764078A JP11764078A JPS5545122A JP S5545122 A JPS5545122 A JP S5545122A JP 11764078 A JP11764078 A JP 11764078A JP 11764078 A JP11764078 A JP 11764078A JP S5545122 A JPS5545122 A JP S5545122A
Authority
JP
Japan
Prior art keywords
recording disk
slanting
photo
beam spot
movement
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.)
Granted
Application number
JP11764078A
Other languages
Japanese (ja)
Other versions
JPS5757770B2 (en
Inventor
Yoshiharu Tanaka
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.)
Mansei Kogyo KK
Original Assignee
Mansei Kogyo KK
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 Mansei Kogyo KK filed Critical Mansei Kogyo KK
Priority to JP11764078A priority Critical patent/JPS5545122A/en
Publication of JPS5545122A publication Critical patent/JPS5545122A/en
Publication of JPS5757770B2 publication Critical patent/JPS5757770B2/ja
Granted 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
    • G11B7/095—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 specially adapted for discs, e.g. for compensation of eccentricity or wobble
    • G11B7/0956—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 specially adapted for discs, e.g. for compensation of eccentricity or wobble to compensate for tilt, skew, warp or inclination of the disc, i.e. maintain the optical axis at right angles to the disc
    • 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

Landscapes

  • Automatic Focus Adjustment (AREA)
  • Optical Recording Or Reproduction (AREA)

Abstract

PURPOSE:To detect an accurate focus signal whose noise signal due to the slanting of a recording disk has been removed, by obtaining two different pieces of information by irradiating two photo detecting elements with a reflected beam from a condenser. CONSTITUTION:When recording disc 1 moves axially by dD without slanting, beam spot 11 on 2nd photo detecting element 10 stays on R1, but when recording disk 1 slants by dtheta, on the other hand, beam spot 11 moves to R2. In addition, when recording disk 1 moves in a direction of photo axis 2a by dD while stay slanting by dtheta, reflected beam 3 reaches R2. Namely, the movement of beam spot 11 on photo detecting element 10 is represented only when slanting angle theta of recording disk 1 changes. For the purpose, the movement of beam spot 11 is detected in the form of a difference output, by which correction circuit 12 corrects the output of 1st photo detecting elememt 6 to extract only the movement of recording disk 1 in the photo- axial direction, so that an accurate focus signal can be obtained.
JP11764078A 1978-09-25 1978-09-25 Focus controller of optical reader Granted JPS5545122A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11764078A JPS5545122A (en) 1978-09-25 1978-09-25 Focus controller of optical reader

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11764078A JPS5545122A (en) 1978-09-25 1978-09-25 Focus controller of optical reader

Publications (2)

Publication Number Publication Date
JPS5545122A true JPS5545122A (en) 1980-03-29
JPS5757770B2 JPS5757770B2 (en) 1982-12-06

Family

ID=14716691

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11764078A Granted JPS5545122A (en) 1978-09-25 1978-09-25 Focus controller of optical reader

Country Status (1)

Country Link
JP (1) JPS5545122A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5776507A (en) * 1980-09-02 1982-05-13 Philips Nv Optical focusing device
JPS57188027A (en) * 1981-04-16 1982-11-18 Euromask Projector with focusing mechanism
JPS62133702U (en) * 1986-02-13 1987-08-22

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5776507A (en) * 1980-09-02 1982-05-13 Philips Nv Optical focusing device
JPS57188027A (en) * 1981-04-16 1982-11-18 Euromask Projector with focusing mechanism
JPS62133702U (en) * 1986-02-13 1987-08-22

Also Published As

Publication number Publication date
JPS5757770B2 (en) 1982-12-06

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