Dynamic information storage or retrieval – Specific detail of information handling portion of system – Radiation beam modification of or by storage medium
Patent
1995-09-07
1997-09-23
Edun, Muhammad N.
Dynamic information storage or retrieval
Specific detail of information handling portion of system
Radiation beam modification of or by storage medium
369110, 369 13, 369 4414, 369 4437, G11B 700
Patent
active
056712065
ABSTRACT:
An optical pickup device for recording/reproducing an optical disc having at least two data storing layers on one side thereof generates a first and second laser beams of same polarization (S-polarized beams) from a first and second laser beam sources. The laser beams are incident on a prism of a cubic type in which a dielectric coating layer for selectively total reflecting or total transmitting depending to a polarizing state of an incident beam is formed at a diagonal surface (45.degree.) of the prism. Instead of the prism of the cubic type, only a dielectric coating plate may be positioned at the diagonal surface of the prism. The first S-polarized beams is total reflected by the dielectric coating layer for reading out information recorded on a first layer of the optical disc. The second S-polarized beams is total reflected toward a polarization converting plate, and thus the beam is converted into P-polarized light to return to the prism. The P-polarized beams is total transmitted through the dielectric coating layer for reading out information recorded on a second layer of the optical disc.
REFERENCES:
patent: 4905214 (1990-02-01), Nagashima
patent: 5408453 (1995-04-01), Holtslag et al.
Daewoo Electronics Co. Ltd.
Edun Muhammad N.
LandOfFree
Optical pickup device 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 pickup device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical pickup device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1940998