A generalized machine for automated flow cytology system design.

A general-purpose multiparameter flow cytophotometry system has been developed for use in the desgin of flow cytophotometers to perform specific tasks in automated cytology. Five separate measurement stations spaced along the axis of a capillary tube can be used to make up to eight optical measurements of individual cells flowing through the capillary. The system uses a broad-band arc source and can measure light scattered at various angles, light absorption by cell constituents and/or dyes and fluorescence of cell constituents and/or fluorochromes, excited directly and/or by energy transfer from neighboring molecules. High numerical aperture optics are used to maximize light-gathering capacity and minimize the effects of cell orientation and eccentricity of position in the fluid stream on measurements. A hard-wired preprocessor is used to detect the presence of cells and adjust sampling timing for changes in cell velocity; the electronic system also controls the gain of the detector photomultiplier tubes to compensate for background variations. Data acquistion and analysis are controled by a small general-purpose digital computer. The system has been used to develop a method and apparatus for blood cell counting and classification.