Particle counter/classifier -partic for blood corpuscles

摘要

'Coulter'-type appts. for counting and classifying particles in suspension in a liq. and more esp. white and red blood corpuscles, in which the electrolyte flows through a small measuring orifice from one container to another, each having an electrode immersed in the electrolyte therein, the suspension to be investigated being ejected from the outlet of a nozzle a short distance upstream of the measuring orifice and coaxial therewith, by the concentric flow of the electrolyte to the orifice and the current between the electrodes, between which a potential difference is maintained, being measured so as to determine the current variation caused by the passage of a particle through the orifice, such variation being a function of the particle dimension, with the improvement whereby two measuring orifices are provided in sequence, together with the appropriate electrode and electrical measuring circuits, the ratio of the lengths and/or dias. of the orifices being such that, using suitable techniques, the particle volume can be determined by the first orifice and the particle cross section by the second orifice.