JPS573231A - Optical reproducer - Google Patents
Optical reproducerInfo
- Publication number
- JPS573231A JPS573231A JP7609380A JP7609380A JPS573231A JP S573231 A JPS573231 A JP S573231A JP 7609380 A JP7609380 A JP 7609380A JP 7609380 A JP7609380 A JP 7609380A JP S573231 A JPS573231 A JP S573231A
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- output
- reference voltage
- oscillator
- inputted
- 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
Links
Landscapes
- Automatic Focus Adjustment (AREA)
- Optical Recording Or Reproduction (AREA)
Abstract
PURPOSE:To exercise highly precise control by canceling a change in oscillation due to fluctuations of temperature, etc., by providing a servocontrol circuit which holds constant a component with a frequency twice the oscillation frequency of a signal obtained by a beam detector. CONSTITUTION:The reflected beam 18 of a beam 2 incident to a track on a disk 1 is detected by photodetector 19 and inputted to an amplifier 22. Its output is inputted to a correcting circuit 33 via a BPF32 for a frequency 2fomega twice that of the output signal. The output of the amplifier 22, on the other hand, is inputted to a comparator 39 via an envelope detecting circuit 37 and an LPF38 and compared with a reference voltage from a reference voltage circuit 40, thereby controlling the correcting circuit 33 by the difference output. The output of the circuit is passed through the envelope detecting circuit 34 and an LPF35 and compared by a level comparing circuit 36 with a reference voltage from a reference voltage circuit 41 to correct the output of an oscillator 30 by inputting the output of the comparator to a level adjusting circuit 31a, thereby supplying the output of the oscillator to a beam spot oscillator. Thus influences of fluctuations of temperature, etc., are canceled easily to exercise highly precise control.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7609380A JPS573231A (en) | 1980-06-06 | 1980-06-06 | Optical reproducer |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7609380A JPS573231A (en) | 1980-06-06 | 1980-06-06 | Optical reproducer |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS573231A true JPS573231A (en) | 1982-01-08 |
JPS6152533B2 JPS6152533B2 (en) | 1986-11-13 |
Family
ID=13595225
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP7609380A Granted JPS573231A (en) | 1980-06-06 | 1980-06-06 | Optical reproducer |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS573231A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007537556A (en) * | 2004-05-12 | 2007-12-20 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Improved servo system, record carrier and playback device |
-
1980
- 1980-06-06 JP JP7609380A patent/JPS573231A/en active Granted
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007537556A (en) * | 2004-05-12 | 2007-12-20 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Improved servo system, record carrier and playback device |
Also Published As
Publication number | Publication date |
---|---|
JPS6152533B2 (en) | 1986-11-13 |
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