Patent ID: 7180592

Claim:
A particle size distribution analyzer comprising; multiple cells; a light source that irradiates light to particles contained in the cells; multiple photo-detectors that detect the light intensity of a diffraction light or a scattering light generated from the particles irradiated by the light; and an information processor that calculates a particle size distribution of the particles based upon light intensity signals transmitted from each of the photo-detectors, wherein, the particle size distribution analyzer further comprises a movement retention unit that retains the multiple cells to be movable between a light irradiation position irradiated by the light from the light source and withdrawal positions established at different positions from the light irradiation position; a stop unit that selectively stops one of the multiple cells at the light irradiation position; and a cell identification means that identifies the cell situated at the light irradiation position, and transmits an identification signal for that cell; and, the information processor is equipped with an operation control program storage unit for storing a plurality of operation control programs, each comprising a program for controlling the operation of the particle size distribution analyzer with respect to one of the multiple cells, and a program switch means that receives the cell identification signal transmitted from the cell identification means, and automatically switches to another of the stored operation control programs corresponding to the cell indicated by the cell identification signal.