Other

Masaharu Horiguchi

Shinji Makikawa

Tohru Mori

Yasushi Maeda

Seiki Ejima

Kazumasa Takada

Emitted light from a light source is separated into two parts through an optical fiber coupler , one is entered in a measured optical module as measurement light, and the other is given a group delay by means of an optical fiber delay line , a reflector , etc., as local light signal, then the local light signal is combined with reflected light signal from the measured optical module through an optical fiber coupler and the reflected light signal and the local light signal are caused to interfere with each other. A polarization controller comprising a polarizer and a polarization rotation device for arbitrarily rotating the polarization state 0 degrees and 90 degrees at the time is used to generate beat signals at the polarization rotation angles, and the sum of the intensities of the beat signals is found, making it possible to measure the light power of the reflected light signal regardless of the polarization state of the local light signal or reflected light signal.

Polarization-independent reflectometry and polarization-independent reflectometer

A silicon substrate is prepared by furnishing a silicon substrate ( ) having a step ( ) of at least 5 &mgr;m high on one surface, forming by high pressure heat oxidation an oxide film ( ) which is thinner than the step, and removing the oxide film on the higher surface region until the silicon surface is exposed in the higher surface region while leaving the oxide film on the lower surface region. Because of excellent electrical properties, minimized warpage, a substantially constant oxygen concentration, and a definitely ascertainable oxide-silicon boundary, the silicon substrate is suitable for use in optical waveguide devices.

Growing community of inventors

Tokyo, Japan

Masaharu Horiguchi