PURPOSE: To obtain an optical AND circuit by applying voltage produced in a photoelectromotive element excited by light traveling in the 2nd optical waveguide to the narrow part of the 1st optical waveguide so as to transmit light.
CONSTITUTION: Two optical waveguides 11, 12 are formed on a substrate 10 of an LiNbO3 crystal. The photoelectromotive element 20 of CdTe or the like is placed on the end of the waveguide 11. The narrow part 13 where single-mode light does not travel by diffusion is formed in the waveguide 12, and electrodes 21 are placed on both sides of the part 13. Light travels in the waveguides 11, 12a, and when the photoelectromotive force produced in the element 20 is applied to the electrodes 21 through a wiring pattern 22, the refractive index of the narrow part 13 of the waveguide 12 is increased to transmit light. This light travels in the waveguide 12b and is emitted. In case where both inputted photo signals IinA and IinB are 1, Iout becomes 1 and an optical AND circuit is obtd.
TAKAGI JIYUNICHI
OGATA SHIROU
MATANO MASAHARU
YAMASHITA MAKI
