Optical disc recording/reproducing apparatus recording/reproduci

Details Optical disc recording/reproducing apparatus recording/reproduci Optical disc recording/reproducing apparatus recording/reproduci

1996-06-21

2000-04-11

Tran, Thang V.

Dynamic information storage or retrieval

Specific detail of information handling portion of system

Radiation beam modification of or by storage medium

369112, 369118, G11B 700

Patent

active

060495189

ABSTRACT:
An optical disc reproducing apparatus includes a semiconductor laser, an objective lens converging a laser beam from the semiconductor laser on a recording surface of an optical disc, a polarization plane rotating unit selectively rotating the plane of polarization of the laser beam according to the thickness of a substrate of the optical disc, and a polarizing filter selectively shading a peripheral portion of the laser beam having the rotated plane of polarization. In one embodiment, a numerical aperture changing unit includes a non-patterned twisted nematic liquid crystal, and the polarizing filter includes a polarizing film having a polarization characteristics at its peripheral portion.

REFERENCES:
patent: 4225873 (1980-09-01), Winslow
patent: 5150234 (1992-09-01), Takahashi et al.
patent: 5281797 (1994-01-01), Tatsuno et al.
patent: 5621719 (1997-04-01), Nomoto

Affiliated with

Also associated with

Rating

Optical disc recording/reproducing apparatus recording/reproduci does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Optical disc recording/reproducing apparatus recording/reproduci, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical disc recording/reproducing apparatus recording/reproduci will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1181834