JPS6476424A - Overwrite detecting system for optical disk device - Google Patents

Overwrite detecting system for optical disk device

Info

Publication number
JPS6476424A
JPS6476424A JP23244487A JP23244487A JPS6476424A JP S6476424 A JPS6476424 A JP S6476424A JP 23244487 A JP23244487 A JP 23244487A JP 23244487 A JP23244487 A JP 23244487A JP S6476424 A JPS6476424 A JP S6476424A
Authority
JP
Japan
Prior art keywords
overwrite
intensity
write
optical disk
reflected light
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.)
Pending
Application number
JP23244487A
Other languages
Japanese (ja)
Inventor
Akira Minami
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP23244487A priority Critical patent/JPS6476424A/en
Publication of JPS6476424A publication Critical patent/JPS6476424A/en
Pending legal-status Critical Current

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  • Optical Recording Or Reproduction (AREA)

Abstract

PURPOSE:To simultaneously write and detect overwrite detection information by detecting overwrite of data with the reflected light of the light which is projected to an overwrite detection information storage area and has an intensity for write. CONSTITUTION:In case of write to the overwrite detection information storage area where detection information is stored, the reflectivity is changed. Then, a phase changing medium is used to increase the intensity of the light for write. The reflected light of the laser light, which has the intensity for write, from the surface of an optical disk of an optical disk device is inputted to a reflected light detector 1. The detector 1 outputs an electric signal which has a level corresponding to the intensity of the reflected light, and this signal is inputted to a comparator 2. The comparator 2 compares this electric signal with a prescribed threshold to output an overwrite detection signal. Since this detection signal has the intensity for overwrite, detection and overwrite are simultaneously performed.
JP23244487A 1987-09-18 1987-09-18 Overwrite detecting system for optical disk device Pending JPS6476424A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP23244487A JPS6476424A (en) 1987-09-18 1987-09-18 Overwrite detecting system for optical disk device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP23244487A JPS6476424A (en) 1987-09-18 1987-09-18 Overwrite detecting system for optical disk device

Publications (1)

Publication Number Publication Date
JPS6476424A true JPS6476424A (en) 1989-03-22

Family

ID=16939369

Family Applications (1)

Application Number Title Priority Date Filing Date
JP23244487A Pending JPS6476424A (en) 1987-09-18 1987-09-18 Overwrite detecting system for optical disk device

Country Status (1)

Country Link
JP (1) JPS6476424A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03116534A (en) * 1989-09-29 1991-05-17 Toshiba Corp Optical disk device
JPH03116533A (en) * 1989-09-29 1991-05-17 Toshiba Corp Optical disk device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03116534A (en) * 1989-09-29 1991-05-17 Toshiba Corp Optical disk device
JPH03116533A (en) * 1989-09-29 1991-05-17 Toshiba Corp Optical disk device

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