Particle analyzer for measuring the resistance and reactance of a particle

A blood cell analyzer which determines the presence of blood cells and for providing data to allow the determination of the opacity of the detected cells comprising:

• cell transporting means, including first and second chambers separated by a small orifice, said blood cells flowing from said first chamber to said second chamber through said orifice;
• a direct current (d.c.) current source;
• means for coupling said current source to said orifice to provide d.c. current through said orifice and a d.c. voltage across said orifice;
• an oscillator, including an active device and a resonant circuit;
• means for coupling said resonant circuit in parallel with said orifice, to provide an alternating current (a.c.) signal through said orifice;
• means for sensing the change in the d.c. voltage across said orifice;
• and
• means for sensing the amplitude of the a.c. signal provided by said resonant circuit.

A blood cell analyzer for determining the presence of blood cells in a sample under test comprising:

• cell transporting means, including first and second chambers separated by a small orifice, said blood cells flowing from said first chamber to said second chamber through said orifice;
• an oscillator, including an active device and a resonant circuit, which provides an alternate current;
• means for coupling said resonant circuit in parallel with said orifice to provide said alternating current signal through said orifice;
• and
• means for sensing the envelope amplitude of said alternating current signal provided by said resonant circuit.

A particle analyzer for determining the presence and certain parameters of particles in a solution, comprising:

• detector means through which said solution passes, said detector means having a certain resistance and reactance, at least one of which changes as a particle passes therethrough;
• a plurality of oscillator means, each providing a different frequency signal;
• coupling means for coupling each of said oscillator means in parallel with said detector means, said coupling means including reactance means, associated with each oscillator means, arranged and valued so that the signal provided by each oscillator means is coupled through a low impedance path to said detector means and through a high impedance path to the other of said plurality of oscillator means;
• and
• means for manifesting the presence of said certain parameters for each of said frequencies, whenever a particle passes through said detector means.