Dynamic information storage or retrieval – Specific detail of information handling portion of system – Radiation beam modification of or by storage medium
Patent
1997-09-16
2000-02-29
Dinh, Tan
Dynamic information storage or retrieval
Specific detail of information handling portion of system
Radiation beam modification of or by storage medium
369 13, 369 4423, 369 4437, 369 4432, 369116, G11B 1100
Patent
active
060318104
ABSTRACT:
An optical information recording/reproducing apparatus records information on an optical information recording medium and/or reproduces the recorded information by irradiating a plurality of light spots on the recording medium. The apparatus includes a first light source for emitting a light beam with a wavelength .lambda..sub.1, and a second light source for emitting a light beam with a wavelength .lambda..sub.2. A light spot forming unit focuses the light beam with the wavelength .lambda..sub.1 and the light beam with the wavelength .lambda..sub.2 through an objective lens, and forms first and second light spots on the information recording medium. The following relations are substantially established: 1.gtoreq.D.sub.1 /W.sub.1.perp. .gtoreq.0.6; 3.2-2.6.times.1n.alpha..gtoreq.D.sub.2 /W.sub.2 .perp..gtoreq.1.0-1.2.times.1n.alpha.; and .alpha.=(.lambda..sub.2 /.lambda..sub.1).times.(D.sub.1 /D.sub.2). D.sub.1 is the diameter of the light beam with the wavelength .lambda..sub.1 which is incident on the objective lens for formation of the first light spot. D.sub.2 is the diameter of the light beam with the wavelength .lambda..sub.2 which is incident on the objective lens for formation of the second light spot. W.sub.1 .perp. and W.sub.2.perp. are the diameters, in a direction corresponding to a track crossing direction of the information recording medium, of the light beams with the wavelengths .lambda..sub.1 and .lambda..sub.2, respectively, incident on the objective lens and forming the first and second light spots, respectively, which corresponds to 1/e.sup.2 a peak intensity of the light beam.
REFERENCES:
patent: 5270987 (1993-12-01), Kaku et al.
patent: 5315573 (1994-05-01), Nakao et al.
patent: 5353274 (1994-10-01), Nishikawa
patent: 5357493 (1994-10-01), Okazaki et al.
patent: 5463610 (1995-10-01), Nishikawa
patent: 5557601 (1996-09-01), Nishikawa
patent: 5586097 (1996-12-01), Nishikawa
patent: 5657305 (1997-08-01), Sasaki et al.
patent: 5784345 (1998-07-01), Maeda et al.
Canon Kabushiki Kaisha
Chu Kim-Kwok
Dinh Tan
LandOfFree
Using two laser sources on a magneto-optical recording medium fo does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Using two laser sources on a magneto-optical recording medium fo, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Using two laser sources on a magneto-optical recording medium fo will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-689228