JPS5718033A - Reproducing device for optical information recording medium - Google Patents

Reproducing device for optical information recording medium

Info

Publication number
JPS5718033A
JPS5718033A JP9132980A JP9132980A JPS5718033A JP S5718033 A JPS5718033 A JP S5718033A JP 9132980 A JP9132980 A JP 9132980A JP 9132980 A JP9132980 A JP 9132980A JP S5718033 A JPS5718033 A JP S5718033A
Authority
JP
Japan
Prior art keywords
beams
divided
control signal
focus
detectors
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
JP9132980A
Other languages
Japanese (ja)
Other versions
JPS6152534B2 (en
Inventor
Osamu Tajima
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.)
Victor Company of Japan Ltd
Original Assignee
Victor Company of Japan Ltd
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 Victor Company of Japan Ltd filed Critical Victor Company of Japan Ltd
Priority to JP9132980A priority Critical patent/JPS5718033A/en
Publication of JPS5718033A publication Critical patent/JPS5718033A/en
Publication of JPS6152534B2 publication Critical patent/JPS6152534B2/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
    • G11B7/0908—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 increase the sensitivity of detection for a focus control signal, by projecting the control signal detecting beam only to a part of a lens aperture which is opposite to a recording medium. CONSTITUTION:The light given from a light source 1 is divided into three beams through a trapezoid prism 20, and the shape of the prism 20 is selected so as to project the beams from imaginary light sources 1R and 1L on only a partial region of a condenser lens 5. The beams from these light sources are reflected on a disk surface 6 and condensed at a detector 7 plus divided detectors 8 and 9 through a half-mirror 4. The cross-section of the condensed beam led to the divided detector is almost semicircular, and the right and left become adverse to each other before and after the focal point. Accordingly even a slight shift of focus increases the output of difference signal of component detectors 8o, 8i, 9o and 9i. Furthermore the shifting directions of beams caused by the shift of focus are reverse to each other on the divided detectors. Thus a large focus control signal is obtained at a terminal 30.
JP9132980A 1980-07-04 1980-07-04 Reproducing device for optical information recording medium Granted JPS5718033A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9132980A JPS5718033A (en) 1980-07-04 1980-07-04 Reproducing device for optical information recording medium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9132980A JPS5718033A (en) 1980-07-04 1980-07-04 Reproducing device for optical information recording medium

Publications (2)

Publication Number Publication Date
JPS5718033A true JPS5718033A (en) 1982-01-29
JPS6152534B2 JPS6152534B2 (en) 1986-11-13

Family

ID=14023402

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9132980A Granted JPS5718033A (en) 1980-07-04 1980-07-04 Reproducing device for optical information recording medium

Country Status (1)

Country Link
JP (1) JPS5718033A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1984004965A1 (en) * 1983-06-13 1984-12-20 Storage Technology Partners Amplitude modulated coarse position error signal generation in an optical disk storage system employing coarse servo tracks
JPS601632A (en) * 1983-06-18 1985-01-07 Mitsubishi Electric Corp Optical recording and reproducing device of information
US4531053A (en) * 1981-09-25 1985-07-23 Sig Societe Industrielle Suisse Railway work machine
US4538061A (en) * 1981-09-25 1985-08-27 Sig Societe Industrielle Suisse Railway work machine
US4720825A (en) * 1984-02-06 1988-01-19 Asahi Kogaku Kogyo Kabushiki Kaisha Optical data reproducing devices having improved trick play capability
US4817074A (en) * 1985-12-19 1989-03-28 Nec Corporation Method and apparatus for detecting the focusing state and positioning accuracy of a light beam directed onto an optical disk tracking guide in an optical recording system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63121154U (en) * 1987-01-31 1988-08-05

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4531053A (en) * 1981-09-25 1985-07-23 Sig Societe Industrielle Suisse Railway work machine
US4538061A (en) * 1981-09-25 1985-08-27 Sig Societe Industrielle Suisse Railway work machine
WO1984004965A1 (en) * 1983-06-13 1984-12-20 Storage Technology Partners Amplitude modulated coarse position error signal generation in an optical disk storage system employing coarse servo tracks
JPS601632A (en) * 1983-06-18 1985-01-07 Mitsubishi Electric Corp Optical recording and reproducing device of information
US4720825A (en) * 1984-02-06 1988-01-19 Asahi Kogaku Kogyo Kabushiki Kaisha Optical data reproducing devices having improved trick play capability
US4817074A (en) * 1985-12-19 1989-03-28 Nec Corporation Method and apparatus for detecting the focusing state and positioning accuracy of a light beam directed onto an optical disk tracking guide in an optical recording system

Also Published As

Publication number Publication date
JPS6152534B2 (en) 1986-11-13

Similar Documents

Publication Publication Date Title
US5016954A (en) Optical pickup and hologram therefor
JPS5752006A (en) Method and device for detecting focus
JPS5718033A (en) Reproducing device for optical information recording medium
JPS6155047B2 (en)
JPS57105831A (en) Detector for optical position
JPS57111837A (en) Signal detecting system of optical information reader
JPS54116904A (en) Optical information reader
JPH03157821A (en) Optical pickup
JPS5744236A (en) Optical information reproducer
JPH0241092B2 (en) KOGAKUTEKIICHIKENSHUTSUSOCHI
JPS5984352A (en) Device for detecting focal error
KR960005480A (en) Focus error detection device
JPS5753839A (en) Optical reproducer
JPS61230633A (en) Focus position detecting device
JPS6020322A (en) Optical disk pickup device
JPS5525853A (en) Tracking device for optical information track
SU1223029A1 (en) Versions of devices for measuring object vibrations
JP3455398B2 (en) Optical disk sensor system
JPS5774841A (en) Control signal detector of optical information reader
JPS6050638A (en) Optical signal detector
JPS57198547A (en) Optical information processor
JPS54104303A (en) Optical system signal reading system
JPS57212631A (en) Focus detector of optical information reproducing device
JPS5644127A (en) Optical pickup
JPS5920169B2 (en) Optical information reproducing device