Kabushiki Kaisha Toshiba

Kei Takakura

Hidehiko Kuroda

Naoto Kume

Kunihiko Nakayama

Mikio Izumi

Yukio Yoshimura

A radiation detection apparatus includes a selecting unit that allows a light having a light emission wavelength and a polarization direction to pass thorough the selecting unit, an optical system that forms an image of the light, a photon detecting unit that observes the image formed by the optical system, and detects the photon in whole range of the entire image, a counting unit that calculates the number of the alpha rays based on a result of counting the photons derived from the light emission of gas excited by the alpha rays, whereby it is possible to sufficiently eliminate background light (noise light) even if background light is strong, and therefore observe weak light emission.

Radiation detection apparatus and radiation detection method

An alpha ray observation device and an alpha ray observation method are provided that can correctly evaluate a signal derived from alpha rays. The alpha ray observation device according to an embodiment includes a device housing, an incident window, a condenser, an optical path changer, and a first optical detector. The device housingis provided with an opening. The incident windowis provided at the opening, and can block beta rays. Emitted light originated by alpha rays caused from the measurement object set outside of the device housingenters the inside of the device housingthrough the incident windowwith beta rays being blocked, and is condensed by the condenser, and the optical path is changed by the optical path changer, and subsequently the light is detected by the first optical detector. The first optical detectoroutputs a signal according to the amount of detected light.

Alpha ray observation device and alpha ray observation method

An embodiment of a radiation detector has: a light collecting member; a photo detector that can receive light collected by the light collecting member and count number of photons; a wavelength selector that can selectively transmit light based on the light emission of gas caused by alpha rays by selectively transmitting light of a wavelength in a specific range; a shielding device that is can switch between an opened state in which it transmits light and a closed state in which it shields light; and a counting unit that calculates an alpha dose based on a difference calculated by subtracting number of noise photons detected in the photo detector within a predetermined time period when the shielding device is in the closed state from the number of photons received by the photo detector within the predetermined time period when the shielding device is opened state.

Radiation detector and radiation detection method

A light detecting unit of an alpha ray observation device observes an alpha ray by measuring generated light that is generated by the alpha ray produced in a region of a to-be-measured object. The light detecting unit has a travel direction changing unit that changes the direction of travel of generated light, a light detector that detects direction-changed light, which is the generated light after the direction of travel is changed, and a shielding member that shields the light detector from radiation and has a portion that is provided on the line from the to-be-measured object to the light detector. The shielding member may also surround the perimeter of the light detector and have an opening to allow generated light to reach the travel direction changing unit.

Growing community of inventors

Yokohama, Japan

Kei Takakura