PURPOSE: To obtain various light guides by providing conductive layers as counter electrodes between the intersection part of a light guide and a substrate and on the surface of the intersection part, and providing a buffer layer between the light guide and conductive layer.
CONSTITUTION: At least one conductive layer 361 of the counter electrode 36 of an optical switch 31 is beltlike on said intersection path 34 and said conductive layer is provided on the bisector of the intersection angle of the lengthwise light guide of the intersection part 34 of said light guide 33. Light in single mode propagating to the optical switch travels straight because a propagation medium does not vary in refractive index if no electric field is applied to the counter electrode. An adequate electric field is applied to the counter electrode to increase the refractive index of the light propagation medium by photoelectric effect, and the total reflection condition is satisfied to allow propagation to another light guide. Therefore, the light is turned on and off corresponding to the on-off operation of a power source when observed from one light guide end. Further, the beltlike conductive layer of the counter electrode on the intersection part is made two-thirds as great as the intersection part to obtain the function of the optical switch.
SETSUNE KENTAROU
WASA KIYOTAKA
OUCHI KENZOU
ADACHI HIDEAKI
