Title:
OPTICAL DEVICE AND OPTICAL HEAD
Document Type and Number:
WIPO Patent Application WO/2004/010197
Kind Code:
A1
Abstract:
An optical device allowing a light from a specified light source to be provided as parallel light even if a temperature variation occurs and manufacturable easily at a low cost and an optical head using the optical device, the optical device comprising a casing (1), a semiconductor laser (2) fixed to the casing (1), a single or a plurality of convex lenses fixed to the inside of the casing (1) to convert radiated light from the semiconductor laser (2) to any of specified substantially parallel light, substantially radiated light, and substantially convergent light, and a collimator lens (3) having a single or a plurality of concave lenses, wherein the focal length of the collimator lens (3) varies according to the temperature variation of the collimator lens (3), and the sum of the variations in refractive index of the single or the plurality of concave lenses against the temperature variation of the collimator lens (3) is larger than that of the variations in refractive index of the single or the plurality of convex lenses.
Inventors:
NAGASHIMA KENJI (JP)
SAITO YOUICHI (JP)
SAITO YOUICHI (JP)
Application Number:
PCT/JP2003/009063
Publication Date:
January 29, 2004
Filing Date:
July 17, 2003
Export Citation:
Assignee:
MATSUSHITA ELECTRIC IND CO LTD (JP)
NAGASHIMA KENJI (JP)
SAITO YOUICHI (JP)
NAGASHIMA KENJI (JP)
SAITO YOUICHI (JP)
International Classes:
G02B7/00; (IPC1-7): G02B13/00; G02B7/02
Foreign References:
| JPH06130267A | 1994-05-13 | |||
| JPH09198697A | 1997-07-31 | |||
| JP2003177295A | 2003-06-27 |
Attorney, Agent or Firm:
Matsuda, Masamichi (1-3 Miyahara 5-chome, Yodogawa-k, Osaka-shi Osaka, JP)
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