Nec Corporation

Mizuki Iwanami

Masafumi Nakada

Norio Masuda

Tsuneo Tsukagoshi

Risato Ohhira

Keishi Oohashi

Hiroshi Fukuda

Masahiro Tsuchiya

Hiroshi Sakai

Yasuhiro Sasaki

Keishi Ohashi

Masatake Takahashi

Junichiro Mataga

Tomonori Yamada

Shigeki Hoshino

Masato Kishi

In an electric/magnetic field probe using an optical fiber, when a stress is applied to the fiber, the polarization state of the light propagating in the fiber changes, and the signal level of the electric or magnetic field detection becomes unstable. For coping with this problem, for suppressing the curve or waggle of the optical fiber caused by a stress applied to the fiber, an electric/magnetic field sensor unit composed of the fiber and EO/MO material is fixed on a quartz substrate, for example, and the part of the fiber other than the sensor unit is stored in an acrylic tube and fixed. Further, polarization adjustment parts like a polarization controller, an optical analyzer or the like is installed in the housing, so that a stress caused by wind pressure or contact is not applied to the fiber connected to the parts.

Probe for electric/magnetic field

An electromagnetic field measuring apparatus capable of measuring an electromagnetic field for a minuscule area in which electronic devices are densely packed with a high sensitivity is provided. In an electromagnetic field measuring apparatus according to the present invention, the amplitude level of signal light (pf) is adjusted by the analyzer () by adjusting its angle with respect to the plane of polarization of the signal light (pf) based on an amplitude level control signal (eb) supplied from the calculation control unit (). An amplitude level control signal (eb) is supplied from the calculation control unit () to the analyzer () based on the spectrum (ea) of an electric signal (ed) measured by an RF spectrum analyzer (). The amplitude level ration between the carrier and the sideband contained in the signal light (ph) incident on the optical receiver () is controlled to a fixed value.

Electromagnetic field measuring apparatus, electromagnetic field measuring method used for the same, and non-transitory computer readable medium storing electromagnetic field measurement control program

Provided is an infrared ray sensor that can conduct a plurality of different types of detection such as temperature detection and gas detection in a simple structure and that is small size and low cost. The infrared ray sensor () includes, on one base (), a first infrared ray detection unit () including at least one infrared ray detection element () including an infrared ray detection material () with physical properties changing depending on properties of incident infrared rays and receives and detects ambient infrared rays, and a second infrared ray detection unit () including at least one infrared ray detection element () having an identical element structure to the infrared ray detection element of the first infrared ray detection unit (), is irradiated with infrared rays X for measurement having specific physical properties, and detects a change in the physical properties of the infrared rays X for measurement.

Infrared ray sensor, infrared ray detection device, and electronic apparatus

There is provided an electromagnetic field measurement apparatus capable of achieving correct and timely circuit operation detection in an area where electronic devices are mounted at high density. An electromagnetic field measurement apparatus includes: a laser light source; a polarized wave controller that linearly polarizes laser light; an optical fiber probe that has an electrooptic material or a magnetooptic material at its leading end and in which the laser light reflected at the leading end is subjected to polarization modulation in accordance with an electric field intensity or a magnetic field intensity; and an analyzer that converts the laser light reflected by the optical fiber probe into intensity modulated light. The laser light source emits time-multiplexed laser light of a plurality of wavelengths different from one another. The electromagnetic field measurement apparatus further includes: an optical circulator that outputs the laser light linearly polarized by the polarized wave controller to a multiplexer/demultiplexer and outputs the laser light input from the multiplexer/demultiplexer to the analyzer; and a multiplexer/demultiplexer that outputs the laser light to different optical fiber probes according to the wavelength of the laser light and outputs the laser light to the optical circulator.

Electromagnetic field measurement apparatus

A magnetic field sensor fabrication method of directly forming, with an aerosol deposition method, at a tip of an optical fiber, a magnetooptical layer having a refractive index that changes depending on a magnetic field, the method includes establishing a relationship of dc&#x2266;d&#x2266;dr among a diameter d of the magnetooptical layer, a diameter dc of a core of the optical fiber, and a diameter dr of a clad thereof.

Electric field/magnetic field sensors and methods of fabricating the same

A stop band or a pass band is generated in a transmission line filter by providing a plurality of dielectric bodies having a periodic structure in the length direction of the transmission line filter and causing Bragg reflection of transmission wave. A voltage is applied to some or all of the dielectric bodies and the frequency of the stop band or the pass band is changed or controlled by adjusting the voltage.

Transmission line filter

An electric field sensor or a magnetic field sensor includes an optical fiber and an electro-optic layer or a magneto-optic layer. The electro-optic layer or a magneto-optic layer is provided on an end surface of an end portion of the optical fiber. The end surface of the optical fiber is a convex shape. The optical fiber may have the end portion with a shape of a substantial cone formed by extending the end portion, and the electro-optic layer or the magneto-optic layer may be formed on a side surface of a front end of the substantial cone. A dielectric layer may be further included between the optic layer and the end surface.

Electric field sensor, magnetic field sensor, electromagnetic field sensor and electromagnetic field measuring system using these sensors

An electric field sensor is obtained by directly forming an electrooptical film of Fabry-Perot resonator structure on a polished surface at a tip of an optical fiber by an aerosol deposition method.

Electric field sensor and method for fabricating the same

A condenser lens is incorporated into the end portion of a magnetic field measuring apparatus including a magneto-optical crystal. Alternatively, the end portion of the magnetic field measuring device includes an optical fiber having a core diameter smaller than that of a normal single-mode optical fiber.

Magnetic field measuring apparatus capable of measuring at high spatial resolution

An inductor device having plural spiral-shaped interconnection structures connected to each other and extending in plural power source layers, the power source layers being in different levels of a multilayer printed board. The printed board having first and second current loops. The loops share part of a common current path.

Multilayer printed board with a double plane spiral interconnection structure

An inter-layer structure between a power layer and a ground layer of a printed circuit board includes an insulative magnetic structure with at least two layers of insulative magnetic substances with different complex magnetic permeability frequency characteristics.

Growing community of inventors

Tokyo, Japan

Mizuki Iwanami