Method of and circuitry for compensating offset voltages in a fo

Details Method of and circuitry for compensating offset voltages in a fo Method of and circuitry for compensating offset voltages in a fo

1991-09-30

1992-09-15

Envall, Jr., Roy N.

Dynamic information storage or retrieval

With servo positioning of transducer assembly over track...

Optical servo system

369 4429, 369 4427, 369 4425, G11B 700

Patent

active

051484234

ABSTRACT:
A method for compensating offset voltages selectively in a focusing circuit that focuses a beam from a source of light on a recording medium and in a tracking circuit that positions a beam of light on data storage tracks on a recording medium. A beam of light reflected from the recording medium is directed onto a photodetector which has a plurality of photodiodes. The difference of the output voltages from the photodiodes is taken for generating an error signal which is stored as a reference during a first stage in open or closed state of the circuit selected. The selected circuit is then closed and a compensation parameter is supplied in a second stage to controls in the selected circuit. The compensation parameter is then varied until the error signal is substantially equal to the stored reference. The compensation of the offset voltages is independent of the tracking circuit, and the offset voltages in the focusing circuit can be compensated when the tracking circuit is closed.

REFERENCES:
patent: 4603410 (1986-07-01), Yoshida
patent: 4707648 (1987-11-01), Minami
patent: 4855983 (1989-08-01), Arai
patent: 5050151 (1991-09-01), Kurz

Affiliated with

Also associated with

Rating

Method of and circuitry for compensating offset voltages in a fo does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of and circuitry for compensating offset voltages in a fo, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of and circuitry for compensating offset voltages in a fo will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-742324