Abstract: A neutron detector without 3He 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 contains 6Li or 10B, 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.

Abstract: 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.

Abstract: A neutron detector without 3He 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 contains 6Li or 10B, 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.

Abstract: An object of the present invention is to provide a method and an apparatus which solve problems such as a measurement error due to air bubbles in a scattering method and a light-shielding method, count loss due to different elements and impossible measurement due to emulsification, and can easily and accurately measure the number, the particle size and the like of fine particles in a fluid at a low cost.

Abstract: 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.

Abstract: 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.

Abstract: A fast gate scanning three-dimensional laser radar apparatus operating on such principles as fluorescence scattering, Raman scattering and differential absorption scattering, which uses a high-sensitivity, two-dimensional imaging CCD camera, an image intensifier or other two-dimensional photodetector suitable for use as a laser echo light signal receiver and detector that is designed to have a gating feature with short time slot, a fast gate scanning feature and a high frame (image capture) repetition rate so that a two- or three-dimensional spatial density distribution of fine particles, environmental pollutants, aerosols and other targets suspended in the atmosphere is acquired instantaneously whereas temporal changes in the direction, speed and flow of the distribution can be remotely monitored.

Abstract: 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.

Abstract: 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.