OPTICAL ELEMENT FOR OPTICAL STORAGE DEVICE AND OPTICAL DEVICE

Japanese Patent JP3660415

B2

PURPOSE: To reduce a size and weight by reduction of the number of optical parts and to stably suppress the mispositioning of a beam by a fluctuation in the wavelength of a semiconductor laser by forming first and second holograms on an optical base body.
CONSTITUTION: The optical base body 4 is formed of a material which allows the transmission of the laser beam emitted from the semiconductor laser 2 and is arranged between the semiconductor laser 2 and an optical storage medium P1. The first hologram H1 is so formed on the optical base body 4 as to allow the transmission of the laser beam, to make this beam incident on the optical storage medium P1 and to diffract the laser beam reflected by the optical storage medium P1 to the inside of the optical base body 4. The second hologram H2 is so formed on the optical base body 4 as to allow the transmission of the one polarization component of the laser beam diffracted in the first hologram H1 and propagated in the optical base body 4, to diffract the other polarization component and to separate both polarization components. As a result, the signal indicating the state of the optical storage medium P1 is detected by detecting a difference in the intensities between the two separated polarization components.

Hironing Yoshikawa
Shinya Hasegawa
Koichi Tezuka

JP773796A

June 15, 2005

January 19, 1996

Click for automatic bibliography generation  

富士通株式会社

G11B11/10; G02B5/32; G11B7/09; G11B7/12; G11B7/123; G11B7/135; G11B7/1353; G11B7/1359; G11B7/1365; G11B11/105; (IPC1-7): G11B11/105; G11B7/09; G11B7/135

JP4364251A
JP6052559A
JP1241028A
JP5089546A

Takashi Ishida
Shigeru Tsuchiya
Toshio Toda
Masaya Nishiyama

Previous Patent: DISPLAY DEVICE AND DRIVING METHOD THEREFOR

Next Patent: ENCODE AND DECODE SYSTEM FOR IMAGE DATA