Apparatus for optically reproducing signals recorded on a rotati

Facsimile and static presentation processing – Facsimile – Recording apparatus

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

369 45, H04N 585, G11B 700

Patent

active

044867913

ABSTRACT:
An optical apparatus reproduces an information signal recorded as pits along track turns of a rotating recording medium. At least one kind of reference signal is recorded along and overlapping the lateral edges of the adjacent track turns of the information signal. A light source projects a first light beam onto the surface of the recording medium to simultaneously reproduce the information and reference signals. A detector responds to reflections of the projected light which includes and reproduces the information signal and the reference signal. The optical system is controlled so that the center of the light beam coincides with the centerline of the track. A circuit separates the reference signal from the total reproduced signal and produces a tracking control signal in response thereto.
The optical system also projects a second light beam onto the recording medium and its reflected component is used for focus control. The depth of focus of the objective lens is substantially equal to or less than two times the pit depth, so that the focussing point of the reproduction light beam coincides with the upper surface of the rotating recording medium or the bottom surface of the pits. Thereby resulting in fine reproduction without introducing second-order harmonic distortion.

REFERENCES:
patent: 3158846 (1964-11-01), Silverman
patent: 3396243 (1968-08-01), McDaniel
patent: 3673412 (1972-06-01), Olson
patent: 3974327 (1976-08-01), Van Dijk
patent: 4110607 (1978-08-01), Honjo et al.
patent: 4125859 (1978-11-01), Oshida et al.
patent: 4135207 (1979-01-01), Greve et al.
patent: 4179708 (1979-12-01), Sheng et al.
patent: 4321621 (1982-03-01), Kinjo et al.
patent: 4322836 (1982-03-01), Kinjo et al.
patent: 4327430 (1982-04-01), Wada et al.
patent: 4331976 (1982-05-01), Kinjo et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Apparatus for optically reproducing signals recorded on a rotati does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus for optically reproducing signals recorded on a rotati, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for optically reproducing signals recorded on a rotati will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1585665

All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.