Title:
OPTICAL DEMULTIPLEXING AND MULTIPLEXING DEVICE
Document Type and Number:
Japanese Patent JPH02146516
Kind Code:
A
Abstract:
PURPOSE:To obtain low-loss variable demultiplexing/multiplexing characteristics with simple, small-sized constitution by providing a polarized light separating element which separates projection light beams from a variable phase difference plate where 1st wavelength light and 2nd wavelength light which differ in retardation have polarizing directions at right angles to each other. CONSTITUTION:Linear polarized light whose polarizing direction slants at 45 deg. to the fast (slow) axis of the phase difference plate 6 is made incident to generate phase differences (retardation) 2Jpi and (2K+1)pi between ordinary light and extraordinary light with the 1st wavelength and the 2nd wavelength by the phase difference plate 6 of electrooptic crystal, and a polarized light separating element 7 separates polarizing directions of light beams projected with retardation of 2Jpi and (2K+1)pi; and an electric field applied to the electrooptic crystal 12 is controlled to vary the wavelength with which the retardation is 2Jpi or (2K+1)pi by the phase difference plate 6. Here, J and K are integers. Consequently, the optical demultiplexer/multiplexer of small-sized, simple constitution is obtained which is low in loss and varies the demultiplexing and multiplexing wavelength characteristics at relatively fast speed.
Inventors:
FUJII YOJI
Application Number:
JP29962588A
Publication Date:
June 05, 1990
Filing Date:
November 29, 1988
Export Citation:
Assignee:
NIPPON TELEGRAPH & TELEPHONE
International Classes:
G02B27/28; (IPC1-7): G02B27/28
Attorney, Agent or Firm:
Hidetoshi Mitsuishi (1 person outside)