Japan Atomic Energy Research Institute

Japan Atomic Energy Agency

Chichibu Fuji Co., Ltd.

Horshin Electronics Co., Ltd.

Hoshin Electronics Co., Ltd.

Akira Ohzu

Masaaki Kato

Takashi Arisawa

Yoichiro Maruyama

Masaki Katagiri

Tatsuya Nakamura

Noriaki Tsutsui

Masumi Ebine

Atsushi Birumachi

Yutaka Yoribayashi

Katsuaki Akaoka

Fumitaka Esaka

Kenichiro Yasuda

Yoji Suzuki

A neutron detector withoutHe gas, provided with a translucent type plate neutron scintillator having the structure capable to emit fluorescence from double-sides; the neutron scintillator is composed of ZnS fluorescent substance and a neutron converter which containsLi orB, and arranged at an angle of 45 degrees from the neutrons which are incident in parallel all together, inside of a cylindrical detector housing with the circular or square section where the specular reflector with the reflectance of 90% or more is arranged internally, and the fluorescence emitted when the neutron enters the scintillator is detected by two photo multipliers arranged on both sides, and signals output from these two photo multipliers are processed to be taken out as a neutron signal.

Neutron detector and neutron image detector with scintillator

A detection apparatus for fine particles in a fluid includes: a flow cell which passes the fluid therein; an X-ray source which irradiates a side face of the flow cell with X-rays; an X-ray detector that detects the intensity of transmission X-rays that the X-rays which have been emitted from the X-ray source have been attenuated by due to the fine particles in the fluid; a fluorescent X-ray detector which detects fluorescent X-rays that are emitted by the fine particles in the fluid due to the X-rays which have been emitted from the X-ray source; and a data processing device which discriminates between fine particles and air bubbles in the fluid based on the fluctuation amount from each reference variable of the intensity of the transmission X-rays and the intensity of the fluorescent X-rays, and calculates the number and the particle diameter of the fine particles.

Method for detecting fine particles in fluid with X-ray

A remote particle counter comprising a pulsed laser generator, laser light emitting optics, scattered light collecting optics, a high-sensitivity two-dimensional photo detector as a scattered light detecting portion having a fast gating capability such as a CCD camera, and a control and measure system, wherein suspended fine particles forming aerosols in the atmosphere which are far away from the site of laser emission are illuminated with laser light, the resulting backward scattered light from the individual fine particles is detected as image, and the number and size distribution of the suspended fine particles are measured at a remote site.

Remote particle counter for remote measurement of the number and size distribution of suspended fine particles in the atmosphere

The improved metal vapor laser capable of cold operation performs plasma etching on a vaporizing metal within a laser tube in the presence of a reactive gas so that the metal is vaporized at temperatures below its boiling point to effect laser oscillation. The laser can be operated at much lower temperatures than a conventional hot-operating version which produces metal vapors by thermal evaporation; in addition, the laser will experience a smaller heat loss while undergoing limited thermal damage to its structural members; further, laser light can be oscillated to produce high output power and, at the same time, the warmup time can be shortened significantly.

Metal vapor laser capable of cold operation

A method of producing a small expansion of laser light, in a pulse laser apparatus, including producing a small preliminary laser light by pumping a laser medium, and then, after an appropriate time lag, then pumping the preliminary laser medium at a higher intensity than the first pumping, thereby producing a laser light which is smaller in beam expansion than in the case where a preliminary pumping is not performed. The laser light which is smaller in beam expansion is due to the population inversion occurring in a small beam expansion part of pulse laser light obtained by the preliminary pumping.

Method of producing a small beam expansion of laser light

Growing community of inventors

Ibaraki, Japan

Akira Ohzu