Optical unit and its use

Optical unit for fibre-optic cable

Optical variable attenuator and optical module

Optical variable-ratio power splitter

Optical via for three dimensional interconnection

Optical viewer with selected magnification

Optical viewing apparatus

Optical wave guide

Optical wave guide and fiber optic insulator

Optical waveform shaping device

Optical waveform shaping device

Optical waveguide

Optical waveguide

Optical waveguide

Optical waveguide

Optical waveguide amplifier

Optical waveguide and display device

Optical waveguide and its charateristics adjusting method

Optical waveguide and method for its manufacture

Optical waveguide and method of fabricating the same