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JPS573236A - Optical information reader - Google Patents

Optical information reader

Info

Publication number
JPS573236A
JPS573236A JP7708680A JP7708680A JPS573236A JP S573236 A JPS573236 A JP S573236A JP 7708680 A JP7708680 A JP 7708680A JP 7708680 A JP7708680 A JP 7708680A JP S573236 A JPS573236 A JP S573236A
Authority
JP
Japan
Prior art keywords
prism
reflected light
light
signal
inexpensive
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
JP7708680A
Other languages
Japanese (ja)
Other versions
JPH0146925B2 (en
Inventor
Kenichi Ito
Toru Musha
Kiichi Kato
Masaaki Yamamoto
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.)
Olympus Corp
Original Assignee
Olympus Optical Co 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 Olympus Optical Co Ltd filed Critical Olympus Optical Co Ltd
Priority to JP7708680A priority Critical patent/JPS573236A/en
Publication of JPS573236A publication Critical patent/JPS573236A/en
Publication of JPH0146925B2 publication Critical patent/JPH0146925B2/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
    • G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam

Landscapes

  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Automatic Focus Adjustment (AREA)
  • Optical Recording Or Reproduction (AREA)

Abstract

PURPOSE:To detect a required signal efficiently with high precision and to obtain an inexpensive, small-sized device by guiding the reflected light of light, condensed on a recording medium, to a four-split photodetecting element via a detection prism which has a reflective surface with a critical angle to the optical axis. CONSTITUTION:Light from a laser light source 51 is converged on a disk 57 with information tracks by way of lenses 52 and 53, a polarizing prism 54, a quarter- wavelength plate, and an objective lens 56. Its reflected light travels backward to pass through the poralizing prism 54, and then is made incident to a four-split photodetector 60, arranged in the far field of the information track, via a detection prism 58 having a reflective surface 59 set nearly at a critical angle to the optical axis of the reflected light. Its output is processed adequately to obtain an information signal and a tracking error signal at the same time. Consequently, a desired signal is detected effectively with high precision and an inexpensive, small-sized device is realized.
JP7708680A 1980-06-10 1980-06-10 Optical information reader Granted JPS573236A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7708680A JPS573236A (en) 1980-06-10 1980-06-10 Optical information reader

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7708680A JPS573236A (en) 1980-06-10 1980-06-10 Optical information reader

Publications (2)

Publication Number Publication Date
JPS573236A true JPS573236A (en) 1982-01-08
JPH0146925B2 JPH0146925B2 (en) 1989-10-11

Family

ID=13623964

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7708680A Granted JPS573236A (en) 1980-06-10 1980-06-10 Optical information reader

Country Status (1)

Country Link
JP (1) JPS573236A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58178905A (en) * 1982-04-13 1983-10-20 帝人株式会社 Aromatic polyamide film insulating electric member
JPH06913A (en) * 1982-09-08 1994-01-11 Toray Ind Inc Aromatic polyamide film composite

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50104539A (en) * 1974-01-15 1975-08-18
JPS5293222A (en) * 1976-01-28 1977-08-05 Philips Nv Recording medium reader
JPS5319806A (en) * 1976-08-09 1978-02-23 Hitachi Ltd Information reproducer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50104539A (en) * 1974-01-15 1975-08-18
JPS5293222A (en) * 1976-01-28 1977-08-05 Philips Nv Recording medium reader
JPS5319806A (en) * 1976-08-09 1978-02-23 Hitachi Ltd Information reproducer

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58178905A (en) * 1982-04-13 1983-10-20 帝人株式会社 Aromatic polyamide film insulating electric member
JPH06913A (en) * 1982-09-08 1994-01-11 Toray Ind Inc Aromatic polyamide film composite

Also Published As

Publication number Publication date
JPH0146925B2 (en) 1989-10-11

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