Patent ID: 8767212

Claim:
A flow cytometer, comprising: a flow cell configured to define a sheath flow encompassing a dyed biological particle; a first optical source configured to irradiate a first light onto the dyed biological particle passing through said flow cell; a second optical source configured to irradiate a second light with non-uniform intensity; a first optical detector configured to detect scattered light or fluorescence from the biological particle to output a first electrical signal corresponding thereto; a beam shaper configured to shape the second light to have substantially uniform intensity along a direction of flow of the flow cell, wherein the second light is shaped by said beam shaper to have substantially uniform intensity along the direction of flow of the flow cell and then irradiated onto the dyed biological particle passing through a plurality of light receiving regions in said flow cell downstream from where the first light is irradiated; a plurality of second optical detectors arranged along said direction of flow of the flow cell, wherein each of said second optical detectors are configured to detect fluorescence from the biological particle in each of the light receiving regions to output a second electrical signal corresponding thereto; and a signal processor configured to sum the second electrical signals, which are output from the plurality of second optical detectors in a plurality of time windows estimated upon when said first optical detector detects the scattered light or the fluorescence, thereby increasing the second electrical signals of the fluorescence from the biological particle excited by the second light.