A new flow chamber and processing electronics for combined laser and mercury arc illumination in an impulse cytophotometer flow cytometer.

A flow cytometer of the impulse cytophotometer (ICP)-type has been developed for two-parameter flow cytometry. It uses two different methods of excitation simultaneously: an argon laser beam focused onto the cell stream within a modified flow chamber, and the light of a high pressure mercury (Hg) lamp using Köhler illumination. The two fluorescence signals are collected sequentially by the same photomultiplier tube. The signals are processed on a cell-by-cell basis using new hardwired analog signal processing electronics enabling their accumulation and display as two-parameter frequency distribution histograms.