| 摘要 |
PURPOSE:To suppress crosstalk at a low level to operate a total reflection type optical switch by extending a refractive index variable area from a full reflection surface up to its side part so that crosstalk from the output port of the 1st waveguide and an input port of the 2nd waveguide practically becomes zero at the time of full reflection operation. CONSTITUTION:The refractive index variable area 29 is extended from the total reflection surface 27 up to the output port 13b side part of the 1st waveguide 13 and the input port 15a side part of the 2nd waveguide 15, and at the time of total reflection operation in the area 29, crosstalk from the output port 13b of the 1st waveguide 13 and the input port 15a of the 2nd waveguide 15 is extended so as to be practically turned to zero. The area 9 is set up so as to form the total reflection surface 27 passing the 1st and 2nd intersecting points 31, 33 and the edge of the area 29 is made to coincide with the side edge of the input port 15a side part out of the 2nd waveguide side edge 15S2 and the side edge of the output port 13b side part out of the 1st waveguide side edge 13S1. An intersecting angle theta between the 1st and 2nd waveguides 13, 15 is set up to >=3 deg. e.g. |
