Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems
Patent
1992-11-27
1994-11-01
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Photocell controls its own optical systems
250214A, 250214AG, 369 4429, 327108, G01J 120
Patent
active
RE0347698
ABSTRACT:
An optical data medium driving apparatus which constitutes amplifiers for an output current signal of a photosensor including a plurality of current mirror circuits having different amplification factors in order to switch, in a wide range, the output current signal of the photosensor. The photosensor detects a quantity of the reflected light corresponding to a variation of the quantity of reflected light from an optical data medium having various characteristics. The output is obtained with high accuracy and in a wide band. A servo-circuit is used for an AGC circuit and normalizes a difference signal from each light receiving surface at a photosensor having a plurality of light receiving surfaces. An A/D converter is given the difference signal as an analog input signal and the sum signal as the reference input signal. The A/D converter outputs an offset binary type digital signal, thereby being inexpensive to produce, easy to be integrated having high function, and high in reliability.
REFERENCES:
patent: 4141004 (1979-02-01), Craven
patent: 4446545 (1984-05-01), Van Dijk
patent: 4528463 (1985-07-01), Kung
patent: 4617654 (1986-10-01), Gross et al.
patent: 4647793 (1987-03-01), Davis
patent: 4661944 (1987-04-01), Van Sluys
patent: 4663749 (1987-05-01), Bierhoff et al.
patent: 4703466 (1987-10-01), Konno
Mitchell "Monolithic Current Source", IBM Tech. Dis. Bull. vol. 13, No. 12, 5/71 p. 3720.
Ito et al., "Improvement of Focusing and Tracking Servos in Optical Disc Memory," SPIE, vol. 529, Optical Mass Data Storage, 1985, pp. 145-149.
Shimoda Kyouji
Yoshimoto Kyosuke
Mitsubishi Denki & Kabushiki Kaisha
Nelms David C.
LandOfFree
Current mirror amplifier for use in an optical data medium drivi does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Current mirror amplifier for use in an optical data medium drivi, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Current mirror amplifier for use in an optical data medium drivi will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1793933