Dynamic information storage or retrieval – Specific detail of information handling portion of system – Radiation beam modification of or by storage medium
Patent
1998-05-07
2000-07-11
Dinh, Tan
Dynamic information storage or retrieval
Specific detail of information handling portion of system
Radiation beam modification of or by storage medium
369 4424, 369 4437, 369 94, 369109, 369118, G11B 700
Patent
active
060883227
ABSTRACT:
An optical disk reader or read/write system for CD or DVD formats. First and second laser diodes operating at different wavelengths have their output beams collimated and directed at a single element objective lens, and are then reflected off the disk back through the lens to a photodetector. The single element objective lens has a central aperture zone and an outer aperture zone, the central zone being profiled to operate at a first numerical aperture at approximately 0.45 and the output beam of the first laser diode is confined to the central aperture zone. The outer aperture zone together with the central aperture zone are profiled to operate at a second numerical aperture, for example 0.60 wherein the output beam of the second laser diode has ray fans extending across the full aperture of the single element objective lens. A diffractive is formed on one surface of the single element objective lens and provides sufficient aspheric surface power for spherical aberration correction as well as correction for spherochromatism. The diffractive also provides sufficient correction for spherical aberration and spherochromatism that the single element objective lens achieves diffraction-limited image quality for both CD and DVD formats.
REFERENCES:
patent: 5044706 (1991-09-01), Chen
patent: 5703862 (1997-12-01), Lee et al.
patent: 5777970 (1998-07-01), Kajiyama et al.
patent: 5808999 (1998-09-01), Yagi
patent: 5835473 (1999-11-01), Shimozono et al.
patent: 5838496 (1998-11-01), Maruyama et al.
patent: 5870369 (1999-02-01), Chung
patent: 5883874 (1999-03-01), Choi
patent: 5889748 (1999-03-01), Shimano et al.
patent: 5933401 (1999-08-01), Lee et al.
patent: 5978346 (1999-11-01), Mizuno et al.
Broome Barry G.
Richard Jenkin A
Chu Kim-Kwok
Dinh Tan
Johnsonbaugh Bruce H.
LandOfFree
Single objective lens for use with CD or DVD optical disks does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Single objective lens for use with CD or DVD optical disks, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Single objective lens for use with CD or DVD optical disks will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-549071