JPS6459635A - Optical information recording and reproducing device - Google Patents

Optical information recording and reproducing device

Info

Publication number
JPS6459635A
JPS6459635A JP21544887A JP21544887A JPS6459635A JP S6459635 A JPS6459635 A JP S6459635A JP 21544887 A JP21544887 A JP 21544887A JP 21544887 A JP21544887 A JP 21544887A JP S6459635 A JPS6459635 A JP S6459635A
Authority
JP
Japan
Prior art keywords
signal
lens
error signal
error
servo
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
JP21544887A
Other languages
Japanese (ja)
Other versions
JPH0727643B2 (en
Inventor
Satoshi Shikichi
Shigeto Kanda
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.)
Canon Inc
Original Assignee
Canon Inc
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 Canon Inc filed Critical Canon Inc
Priority to JP21544887A priority Critical patent/JPH0727643B2/en
Publication of JPS6459635A publication Critical patent/JPS6459635A/en
Publication of JPH0727643B2 publication Critical patent/JPH0727643B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Landscapes

  • Moving Of The Head For Recording And Reproducing By Optical Means (AREA)

Abstract

PURPOSE:To attain servo locking without error even when noise is invaded in an error signal due to a flaw on a medium face of an optical card by varying an error signal comparison reference value depending on the direction moving a spot. CONSTITUTION:A triangle wave generating circuit 306 brings a signal J to an 'H' level when an objective lens 110 is parted from an optical card and to an 'L' level when the lens is approached to the card. The signal J is given to an inverter 303 and a NAND gate 301, the NOR gate output E is brought into an 'L' level only when the error signal A is negative more than V-volt and the lens is parted, and the output is brought to 'L' only when the error signal A is positive more than a V+ volt and the lens is approached to the card. When the moving direction of the lens differs, the reference value comparing the servo error signal is switched to V+, V-. Through the constitution above, even when the servo signal A includes noise NO, the signal F does not immediately go to 'H', the servo loop is closed in response to the output E and an automatic focusing is executed without error.
JP21544887A 1987-08-31 1987-08-31 Optical information recording / reproducing device Expired - Fee Related JPH0727643B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP21544887A JPH0727643B2 (en) 1987-08-31 1987-08-31 Optical information recording / reproducing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP21544887A JPH0727643B2 (en) 1987-08-31 1987-08-31 Optical information recording / reproducing device

Publications (2)

Publication Number Publication Date
JPS6459635A true JPS6459635A (en) 1989-03-07
JPH0727643B2 JPH0727643B2 (en) 1995-03-29

Family

ID=16672528

Family Applications (1)

Application Number Title Priority Date Filing Date
JP21544887A Expired - Fee Related JPH0727643B2 (en) 1987-08-31 1987-08-31 Optical information recording / reproducing device

Country Status (1)

Country Link
JP (1) JPH0727643B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0478703U (en) * 1990-11-20 1992-07-09

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0478703U (en) * 1990-11-20 1992-07-09

Also Published As

Publication number Publication date
JPH0727643B2 (en) 1995-03-29

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Legal Events

Date Code Title Description
LAPS Cancellation because of no payment of annual fees