JPS5737745A - Optical information reader - Google Patents

Optical information reader

Info

Publication number
JPS5737745A
JPS5737745A JP11445280A JP11445280A JPS5737745A JP S5737745 A JPS5737745 A JP S5737745A JP 11445280 A JP11445280 A JP 11445280A JP 11445280 A JP11445280 A JP 11445280A JP S5737745 A JPS5737745 A JP S5737745A
Authority
JP
Japan
Prior art keywords
luminous flux
prism
photodetector
quarter
same time
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
JP11445280A
Other languages
Japanese (ja)
Other versions
JPS639304B2 (en
Inventor
Kenichi Ito
Kiichi Kato
Toru Musha
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 JP11445280A priority Critical patent/JPS5737745A/en
Publication of JPS5737745A publication Critical patent/JPS5737745A/en
Publication of JPS639304B2 publication Critical patent/JPS639304B2/ja
Granted legal-status Critical Current

Links

Landscapes

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

Abstract

PURPOSE:To obtain a tracking and a focusing signal at the same time by causing reflected light from an optical disk, which has a pit with some depth other than an integer multiple of a quarter of the wavelength of light, to strike four photodetecting elements through a detection prism. CONSTITUTION:Reflected light from a disk is condensed by an objective 56 into nearly parallel luminous flux, which strikes a detection prism 58, having a reflecting surface 59 set nearly at a critical angle to the optical axis of the reflected luminous flux, through a quarter-wavelength plate 55 and a polarizing prism 54. The detection prism 58 is arranged with the incidence surface of its reflecting surface 59 at right angles to the direction of an information track to direct emitted luminous flux to a photodetector 60 arranged in the far field of the information track. Thus, a tracking error signal and a focusing error signal are obtained at the same time from outputs of the photodetection areas 60A-60D of the photodetector 60.
JP11445280A 1980-08-19 1980-08-19 Optical information reader Granted JPS5737745A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11445280A JPS5737745A (en) 1980-08-19 1980-08-19 Optical information reader

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11445280A JPS5737745A (en) 1980-08-19 1980-08-19 Optical information reader

Publications (2)

Publication Number Publication Date
JPS5737745A true JPS5737745A (en) 1982-03-02
JPS639304B2 JPS639304B2 (en) 1988-02-26

Family

ID=14638076

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11445280A Granted JPS5737745A (en) 1980-08-19 1980-08-19 Optical information reader

Country Status (1)

Country Link
JP (1) JPS5737745A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62124146U (en) * 1986-01-29 1987-08-06
US5859819A (en) * 1995-07-17 1999-01-12 Fujitsu, Limited Tracking and focus control system for optical disk apparatus

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62124146U (en) * 1986-01-29 1987-08-06
US5859819A (en) * 1995-07-17 1999-01-12 Fujitsu, Limited Tracking and focus control system for optical disk apparatus

Also Published As

Publication number Publication date
JPS639304B2 (en) 1988-02-26

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