Title:
OPTICAL SPACE DECODING METHOD
Document Type and Number:
Japanese Patent JPH0375733
Kind Code:
A
Abstract:
PURPOSE:To remove the light in unnecessary positions and to allow the constitution of arbitrary decoding patterns by installing a mask corresponding to the decoding position in the final stage at the time of spacial decoding. CONSTITUTION:Only the light existing in the spacially separated position corre sponding to a logical computation is selected from incident light by a kernel 1-4. A quarter-wave plate 1-5 circularly polarizes linearly polarized light and a birefringent plate 1-6 advances the linerly polarized light component in a horizontal direction rectlinearly and moves the linerly polarized light component in a perpendicular direction to different routes. A quarter-wave plate 1-7 polarizes the linearly polarized light in the horizontal/perpendicular directions to clockwise/counterclockwise circularly polarized light. A birefringent plate 1-8 moves the linearly polarized light component in the horizontal direction. Finally, the decoded light 1-15 is outputted through the mask 1-9. The mask 1-9 allows the transmission of the light only in one grating among four and shuts off the rest. The appearance of the light in the unnecessary positions is obviated in this way and the constitution of the arbitrary decoding patterns is attained by the combination of the elements for adjusting the polarized light and the birefringent plates, etc.
Inventors:
HASHIMOTO HITOSHI
KITAYAMA KENICHI
KITAYAMA KENICHI
Application Number:
JP21270589A
Publication Date:
March 29, 1991
Filing Date:
August 18, 1989
Export Citation:
Assignee:
NIPPON TELEGRAPH & TELEPHONE
International Classes:
G02F3/00; G06E1/00; (IPC1-7): G02F3/00; G06E1/00
Attorney, Agent or Firm:
Suzuki Makoto
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