Abstract: A cell analyzing apparatus which employs flow cytometry to obtain the concentration (the cell count per unit volume) of a specimen under examination is adapted to measure either the cell count of a control specimen the concentration of which is known or the length of time the control specimen is measured. The concentration of the specimen under examination is calculated based upon the cell count thereof obtained over a length of measurement time identical with the length of measurement time of the control specimen. Alternatively, the concentration of the specimen under examination is calculated based upon the length of measurement time thereof needed to obtain a cell count identical with that of the control specimen.

Abstract: In a cell analyze apparatus, a light beam is irradiated onto cells (or particles like the cells) flowing through a flow cell so as to measure cell light information for each cell with respect to a plurality of parameters (for example, the forward scattered light intensity, the right angle scattered light intensity and the intensity of fluorescence by different dye). Based on a minimal point of a histogram associated with the cell light information with respect to one or more parameters, the cell population is subdivided into fractions. When the minimal point is missing in the histogram, the parameters above are converted by use of a predetermined conversion expression (for example, a coordinate conversion is effected on the parameters) such that a minimal point is detected from the histogram of cell light information related to the new parameters obtained by the conversion, thereby subdividing an objective cell population.