| 摘要 |
<p>In an optical waveguide device (20), a plurality of optical directional coupler switches (22-25) are provided on a substrate (21), and light input and output terminals (26,27; 29,30) are also provided to be coupled to the optical directional coupler switches. Each of the optical directional coupler switches is provided with a pair of parallel waveguides across which a voltage can be applied. One (22) of the optical directional coupler switches operates with independence on polarization of light having a first predetermined wavelength by defining a width of the parallel waveguides and a distance therebetween to be first predetermined values, and another (24) of the optical directional coupler switches operates with independence on polarization of light having a second predetermined wavelength by defining a width of the parallel waveguides and a distance therebetween to be second predetermined values. The parallel waveguides of the first and second ones of the optical directional coupler switches are provided by diffusing films of the same thickness deposited in a predetermined pattern on the substrate by a predetermined diffusing condition. The waveguide device can be used in an optical time-domain reflectometer (OTDR), (Fig. 11). An optical directional coupler may be provided (42, Fig. 12) to provide a dividing function for wavelength multiplexed light. <IMAGE></p> |
