Matsushita Electric Industrial Co., Ltd.

Doryokuro Kakunenryo Kaihatsu Jigyodan

Yoshitake Yasuno

Masaru Ikedo

Tadaoki Yamashita

Masafumi Watari

Osamu Yamamoto

Masatoshi Kitagawa

Takashi Hirao

Hiroshi Tsutsui

Ryuma Hirano

Yukihiro Nomura

Shinso Takeda

Hideharu Ishiguro

Yoshio Mito

A heterostructure diode is produced by a plasma CVD process. A defect caused on a silicon single crystal substrate by plasma deposition during formation of an amorphous semiconductor film leads to a problem of increase in the dark current due to the defect level. This defect is compensated for by active hydrogen contained in the amorphous semiconductor film so as to reduce the dark current. This can be effected by an annealing process conducted after formation of the heterojunction diode. The RF power is set low in the beginning period of formation of the semiconductor film. A radiation detecting apparatus is provided in which a plurality of the heterostructure diodes are integrated on a common substrate.

Method of forming a heterostructure diode

A complex personal dosimeter including a gamma- and beta-ray dosimeter block and a neutron dosimeter block. These two blocks are enclosed in a badge case type package so that a person can secure the dosimeter on his clothing. The gamma- and beta-ray dosimeter block consists of four thermoluminescent elements in combination with plastic filters having different thickness. The neutron dosimeter block consists of four thermoluminescent elements in combination with cadmium and tin filters. This complex dosimeter can individually measure or estimate the radiation doses such as gamma-rays, beta-rays, thermal neutrons, epithermal neutrons and fast neutrons over a wide range of doses, and can also obtain information on the energy of the radiation.

Complex personal dosimeter

An image display device comprises first and second polarizers having their planes of polarizations oriented at right angles to each other and an electrooptic plate of ferroelectric ceramic material interposed between the first and second polarizers. A matrix electrode arrangement is secured to one surface of the ceramic plate to cause crystallographic structural changes to occur under the influence of a locally generated electric field, so that light passing through the first polarizer is refracted by an amount proportional to the magnitude of the electric field and emerges from the second polarizer with an intensity proportional to the electric field. The electrode arrangement includes a plurality of row electrodes and a plurality of column electrodes to define a plurality of elemental picture areas. In each elemental area the electrode arrangement includes a diode, first parallel finger electrodes connected to a row electrode via the diode and second parallel finger electrodes connected to a column electrode and staggered relative to the first finger electrodes.

Image display device utilizing birefringence properties of ferroelectric

A method of thermoluminescent dosimetry employing infrared radiation heating of a dosimeter. An incandescent lamp is used for the source of infrared radiation. The dosimeter is provided with a infrared radiation absorbing layer connected thermally to a thermoluminescent material layer. The infrared radiation absorbing layer is irradiated with infrared radiation, so that thermoluminescent material is not directly irradiated. The lamp is initially powered whereby the dosimeter is heated by infrared radiation of such high intensity as to tend to cause a heat equilibrium in the dosimeter above the temperature where thermal radiation is generated from the dosimeter. Then the power supplied to the lamp is cut or decreased, so that the dosimeter is heated by the afterglow of the lamp. Therefore the rate of temperature rise of the dosimeter becomes quite slow in the latter half of heating process, whereby the temperature of dosimeter easily falls into the required range.

Method of reading thermoluminescent dosimeter

A thin layer of thermoluminescent material is formed on a substrate to form an image storage panel. A radiation image is projected onto the panel, and is stored by the thermoluminescent material. For reading, the panel is scanned by an infrared laser beam, and thermoluminescence proportional to the dose is emitted at the point of impingement of the laser beam. By scanning the storage panel with the laser beam, and by detecting the thermoluminescence, a series of emissions is obtained in the form of a video signal which is used to drive a display device.

Device for storage and display of a radiation image

Growing community of inventors

Kyoto, Japan

Yoshitake Yasuno