Title:
OPTICAL DEVICE
Document Type and Number:
Japanese Patent JP2001291266
Kind Code:
A
Abstract:
To use the same light receiving element for detecting a reflected luminous flux from an information recording medium and to reduce the area of the light receiving element.
A luminous flux 8 exited from a semiconductor laser element 1 and a luminous flux 9 exited from a semiconductor laser element 2 are condensed/reflected on/from the information recording medium 4 by an objective lens 3 being a condensing means, and again are made incident on a hologram element 5 being a luminous flux branching means via the objective lens 3. The luminous fluxes from the information recording medium 4 are diffracted in the X direction in the figure by the hologram element 5, and the 1st-order diffracted light are guided to the light receiving element 7.
Inventors:
NAKANISHI NAOKI
TAKASUKA SHOICHI
SAITO YUKIO
NAKANISHI HIDEYUKI
TAKASUKA SHOICHI
SAITO YUKIO
NAKANISHI HIDEYUKI
Application Number:
JP2000100313A
Publication Date:
October 19, 2001
Filing Date:
April 03, 2000
Export Citation:
Assignee:
MATSUSHITA ELECTRIC IND CO LTD
International Classes:
G02B5/18; G11B7/125; G11B7/135; (IPC1-7): G11B7/135; G02B5/18; G11B7/125
Attorney, Agent or Firm:
Fumio Iwahashi (2 others)
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