Abstract
A new ion counting system useful in pressure measurement with laser was constructed. The system is composed of a microchannel-plate intensifier, a CCD camera, a frame buffer, a particle counter, and a personal computer. By applying it to detection of acetone ions ionized by an excimer laser pulse, it was confirmed that the system has i) a high peak counting rate (exceeding 1010 cps), ii) linear response to the number of incident ions, and iii) higher accuracy than conventional analog detection system. The detection limit in the pressure measurement by laser with the present system is also discussed, and the measurement in the pressure range between 10-10 Pa and 100 Pa is projected.
