Flow cytometer

Claim 1

A flow cytometer comprising: a. means for transporting a stream of particles having cells in suspension in a substantially vertical particle stream, such that each cell passes singly in a vertical direction through an analysis zone; b. a light source for directing a light beam to intersect said particle stream at said analysis zone, such that only a single cell is exposed to said light beam at one time; c. an optical detection means for detecting scattered or fluorescent light pulses from each cell as it passes through said analysis zone, said optical detection means comprising a shell with a substantially spherical shape and having a substantially vertical passage therethrough, through which said substantially vertical particle stream is directed, and said analysis zone being located substantially centrally within said spherically shaped shell, and said shell having an array of apertures therein around said analysis zone, and a plurality of optical fibers being provided, with each optical fiber extending through an aperture in said spherically shaped shell to collect light at a particular radial axis defined by the radial position of the aperture in the shell, and wherein each optical fiber collects light within a collection angle defined by the diameter of the spherically shapted shell, the outer perimeter of the optical fiber, and the distance of the end of the optical fiber from said analysis zone, and each aperture includes means for adjustably securing the optical fiber passing therethrough to adjust the distance of the end of the optical fiber from said analysis zone, and thereby the collection angle of the optical fiber; and d. electronic means connected to said optical fibers for converting the light collected by said optical fibers into electrical impulses and analyzing said impulses for the desired information.