Title:
WAVEGUIDE TYPE OPTICAL BRANCHING ELEMENT
Document Type and Number:
Japanese Patent JPH04179905
Kind Code:
A
Abstract:
PURPOSE:To drastically ease the wavelength dependency of coupling rate in a desired wavelength band by making the width of a central waveguide differ from the width of two outside waveguides on both sides of the central waveguide in a coupling area in a directional coupler. CONSTITUTION:This element is provided with a silicon substrate 1, the quartz optical waveguides 1a-1c formed on the substrate 1, the directional coupler 2 which makes the optical waveguides 1a-1c close to each other at one spot, and the optical waveguides 2a-2c in the directional coupler 2. Among the three optical waveguides 2a-2c in the coupling area in the coupler 2, the width of the central optical waveguide 2b is made to differ from the width of the two outside optical waveguides 2a and 2c, the width is the same between the two waveguides 2a and 2c mutually, then the depth is all the same among the three waveguides 2a-2c. Therefore, practical structure for producing the element by the combination of a waveguide film accumulating method and reactive ion etching, etc., is obtained. Thus, the wavelength dependency of coupling rate is drastically eased in the desired wavelength band.
Inventors:
TAKAGI AKIHIRO
JINGUJI KANAME
KAWACHI MASAO
JINGUJI KANAME
KAWACHI MASAO
Application Number:
JP30991990A
Publication Date:
June 26, 1992
Filing Date:
November 14, 1990
Export Citation:
Assignee:
NIPPON TELEGRAPH & TELEPHONE
International Classes:
G02B6/122; G02B6/28; (IPC1-7): G02B6/12; G02B6/28
Attorney, Agent or Firm:
Yoshikazu Tani