Dynamic information storage or retrieval – Specific detail of information handling portion of system – Radiation beam modification of or by storage medium
Patent
1995-03-17
1996-04-30
Epps, Georgia Y.
Dynamic information storage or retrieval
Specific detail of information handling portion of system
Radiation beam modification of or by storage medium
369110, 369109, 369 54, 369 4437, G11B 700
Patent
active
055131646
ABSTRACT:
An optical head has a first light source for emitting a first light beam having a first wavelength, a second light source for emitting a second light beam having a second wavelength larger than the first wavelength, and an optical system for guiding the first and second light beams to an optical disc and guiding light beams reflected by the optical disc to an optical detector. The optical system, includes an objective lens, a beam splitter for reflecting the first light beam and the S-polarized component of the second light beam and transmitting the P-polarized component of the second light beam, and a quarter wavelength plate. When a high density medium is set against the optical head, recording is performed by the second light beam and reproduction is performed by the first light beam. When a low density medium is set against the optical head, recording and reproduction are carried out by the second light beam. A single optical head provides read/write compatibility with optical discs of different densities, and recording and reproduction can be made on a high density optical disc.
REFERENCES:
patent: 4621351 (1986-11-01), Baer et al.
patent: 4700336 (1987-10-01), Yoshida et al.
patent: 4730293 (1988-03-01), Pierce et al.
patent: 4800550 (1989-01-01), Yamauchi
patent: 5033040 (1991-07-01), Fujita
patent: 5068843 (1991-11-01), Takeshita et al.
patent: 5161243 (1992-11-01), Ishida et al.
patent: 5202789 (1993-04-01), Tanaka
patent: 5295125 (1994-03-01), Oonishi et al.
Sugaya Toshihiro
Tanaka Masahiko
Edun Muhammad N.
Epps Georgia Y.
Kabushiki Kaisha Toshiba
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