Abstract: Initial values including measurement conditions are set at pre-measurement executed prior to main measurement. An area on a sample of a cell population wider than that for the main measurement is two-dimensionally scanned at a high speed in accordance with the set initial values to acquire statistic data of the cell population. Measurement conditions used for the main measurement are determined based on the acquired statistic data.

Abstract: The invention provides a novel preparation process of a polycondensation type polymer, an excellent polymer which is represented by lactic acid and the preparation process of the polymer, a polycondensation agent used for the preparation process, and an intermediate. Specifically, the invention provides a preparation process of the polycondensation type polymer, for example, polyamide, polyimide, polythioester and polyester, comprising bonding a carboxyl group comprising compound with an active hydrogen group comprising compound in the presence of haloiminium salt. The invention provides excellent polylactic acid having a controlled D/L-isomer ratio in the repeating structural units and preparation process of polylactic acid, and further provides a haloiminium salt compound used for the preparation process and an intermediate compound of acid chloride.