JPS5577041A - Optical recording carrier reader - Google Patents

Optical recording carrier reader

Info

Publication number
JPS5577041A
JPS5577041A JP15134378A JP15134378A JPS5577041A JP S5577041 A JPS5577041 A JP S5577041A JP 15134378 A JP15134378 A JP 15134378A JP 15134378 A JP15134378 A JP 15134378A JP S5577041 A JPS5577041 A JP S5577041A
Authority
JP
Japan
Prior art keywords
optical system
servo control
detector
information
detection
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
JP15134378A
Other languages
Japanese (ja)
Inventor
Keiichiro Horai
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.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial 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 Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP15134378A priority Critical patent/JPS5577041A/en
Publication of JPS5577041A publication Critical patent/JPS5577041A/en
Pending legal-status Critical Current

Links

Landscapes

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

Abstract

PURPOSE: To make rapid and stable leading-in of automatic focus control of a reading optical system possible by opening a gate to perform servo control of the optical system dependent upon phase comparison only when read information dependent upon a photo detector becomes over a prescribed value.
CONSTITUTION: Information of disc 17 is read by photo detectors 18a and 18b, and the detection output of detector 18b passes through BPF19, envelope detector 23 and waveform shaping circuit 24; and when the detection output becomes over a prescribed value, gate 22 is opened. Therefore, a signal according to phase difference of detection outputs of detectors 18a and 18b generated by phase comparator 21 is applied to voice coil 27 to perform servo control of focusing of object lens 16 of the reading optical system. Consequently, this servo control does not respond to needless noise and detection outputs of information non-recording parts and recording parts, and leading-in of automatic control is performed rapidly and stably even if a system of a narrow focus error detection range is adopted.
COPYRIGHT: (C)1980,JPO&Japio
JP15134378A 1978-12-06 1978-12-06 Optical recording carrier reader Pending JPS5577041A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15134378A JPS5577041A (en) 1978-12-06 1978-12-06 Optical recording carrier reader

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15134378A JPS5577041A (en) 1978-12-06 1978-12-06 Optical recording carrier reader

Publications (1)

Publication Number Publication Date
JPS5577041A true JPS5577041A (en) 1980-06-10

Family

ID=15516487

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15134378A Pending JPS5577041A (en) 1978-12-06 1978-12-06 Optical recording carrier reader

Country Status (1)

Country Link
JP (1) JPS5577041A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58102340A (en) * 1981-12-11 1983-06-17 Teac Co Optical reproducing device
EP0569942A3 (en) * 1992-05-12 1994-01-12 United Parcel Service Inc

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58102340A (en) * 1981-12-11 1983-06-17 Teac Co Optical reproducing device
EP0569942A3 (en) * 1992-05-12 1994-01-12 United Parcel Service Inc

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