Particle analyzing apparatus and method for determining nuclear shift index

Claim 1

A particle analyzing apparatus for determining a nuclear shift index of a particle, the apparatus forming a detecting zone by irradiating a zone, in which particles flow substantially in single file, with a laser beam in a direction perpendicular to the direction of particle flow, and detecting at one or a plurality of locations, an optical change produced in the detecting zone when particles pass through the detecting zone one at a time, thereby obtaining one or plural types of signals with respect to a single particle, said apparatus comprising: a laser beam irradiating zone for performing irradiation with said laser beam formed to be narrower than a diameter of a particle nucleus in the direction of particle flow and wider than the diameter of the particle nucleus in a direction perpendicular to the particle flow, and detecting scattered light emitted by the particle nucleus, thereby obtaining a particle signal; first characteristic quantity extracting means for extracting high-frequency components contained in the particle signal, in order to determine a degree of complexity of the particle nucleus; second characteristic quantity extracting means for extracting a magnitude of a difference between the particle signal and a signal obtained by flipping over said particle signal in terms of time, in order to determine a degree of symmetry of said particle nucleus; and means for determining the nuclear shift index from said first and said second characteristic quantity extracting means.

Claim 5

The apparatus according to any one of claims 1 to 3, wherein said second characteristic quantity extracting means comprises: an A/D converter for sampling and successively converting said particle signal into digital data at equally spaced clock pulses; clock means coupled to said A/D converter of said second characteristic quantity extracting means for producing equally spaced clock pulses; two memory means connected to an output side of said A/D converter for successively storing sampling data indicative of the particle signal while a single particle signal is present; a subtracter connected to an output side of one memory means and to an output side of the other memory means for successively calculating, with regard to a single particle signal, an absolute value of a difference between data successively outputted by said one memory means in a sequence the same as the passage of time and data successively outputted by said other memory means in a sequence the same as the passage of time and data successively outputted by said other memory means in a sequence that is the reverse of the passage of time, said calculation being performed after the A/D conversion ends; and an accumulator connected to an output side of said subtracter for successively cumulatively adding data outputted by said subtracter.