Matsushita Electric Industrial Co., Ltd.

Yuko Takei

Yoshinori Takeuchi

Hidehiko Negishi

Ken Idota

Yoshihiko Honjoya

An optic rotation sensing apparatus includes a light source emitting light. The light emitted from the light source is transmitted to a sensing loop which provides a phase difference between opposite-direction light waves in response to a rotation. Return light outputted from the sensing loop is transmitted to a photodetector. A device modulates a phase of light propagating in the sensing loop. Another device depolarizes light propagating in the sensing loop. The invention further controls and processes an output signal representing the output of the photodetector at a phase at which a level of an AM noise component of the output signal is minimized.

Optic rotation sensing apparatus and related method including providing

An optical phase modulator for use with a fiber optic sensor such as a fiber optic gyroscope includes a piezoelectric vibrator which is asymmetric in at least one cross-sectional shape thereof, a pair of electrodes for applying a voltage to said piezoelectric vibrator, and an optical fiber joined to at least a portion of said piezoelectric vibrator by adhesive bonding. The piezoelectric vibrator has a cavity defined therein, and one of said electrodes is disposed on a surface of said piezoelectric vibrator which defines said axial cavity, the other electrode being disposed on an outer surface of said piezoelectric vibrator. The piezoelectric vibrator may be cylindrical, elliptically cylindrical, or planar in shape. The cavity may be cylindrical or elliptically cylindrical in shape.

Growing community of inventors

Tokyo, Japan

Yuko Takei