Kabushiki Kaisha Toshiba

Toshiba Industrial Products Manufacturing Corporation

Toshiba Industrial Products and Systems Corporation

Tsuyoshi Kuwabara

Masao Takahashi

Tokihiro Umemura

Junichi Sato

Masahiro Hamaguchi

Takashi Miyabe

Kinichi Sasaki

Teruhiko Maeda

Miwa Takeuchi

Mitsuhiro Fujikawa

A polarizing optical system () is disposed perpendicular to an optical axis of incoming light from a light source (), having the optical axis () as a center axis, and configured for polarization of incoming light to a prescribed reference state, an electro-optical device () is disposed perpendicular to the optical axis, having the optical axis as a center axis, and adapted, as a voltage to be measured is imposed thereon, to respond to the imposed voltage by polarizing light polarized by the polarizing optical system (), and an analyzer () is disposed perpendicular to the optical axis, having the optical axis as a center axis, and adapted for detection of light polarized by the electro-optical device (), to irradiate a detector () configured for conversion of incoming light into an electric signal.

Optical voltage sensor

The present invention provides a photosensor that uses a phase modulation technique for optical detection and conducts a highly accurate measurement. The photosensor uses a phase change difference of light propagated through a polarization preserving fiber with respect to tensile stress and employs proper polarization preserving fibers for a phase modulator, light-transmitting polarization preserving fiber, and coil-shaped polarization preserving fiber, to achieve a highly accurate measurement.

Phase modulator, phase modulator assembly, and photosensor

An optical voltage transformer is connected with an external electric device and includes a primary electrode to which a measured voltage is applied by the external electric device, a first secondary electrode provided oppositely to the primary electrode, an insulation layer provided between the primary and first secondary electrodes and constituting an insulation cylinder integrally formed with the primary and first secondary electrodes, a ground layer provided on an outer circumference of the insulation cylinder and around the first secondary electrode for securing a capacitance by interposing the insulation layer between the ground layer and the first secondary electrode, and an electro-optic element for measuring a voltage between the first secondary electrode and the ground layer. According to the optical voltage transformer, measurement of the measured voltage can be done with high accuracy without affected by its surrounding environment and its downsizing can be achieved by reducing the number of its components.

Optical voltage transformer

Growing community of inventors

Mie-gun Mie, Japan

Tsuyoshi Kuwabara