Patent ID: 7485888

Claim:
A multicolor particle analyzer including: a capillary providing a predetermined detection volume; means for projecting a light beam through said capillary to illuminate said detection volume in said capillary; means for causing a fluid containing sample particles which naturally fluoresce or are tagged to fluoresce and emit light at one or more distinct wavelengths to flow along the capillary through said detection volume; a tunable filter adapted to sequentially shift pass band between two or more wavelengths multiple times as each particle passes through the illuminated detection volume, thereby when in operation the tunable filter sequentially passes emitted light at the two or more wavelengths in a predetermined direction; and a single fluorescence detector disposed in the predetermined direction for receiving and detecting the emitted light at the two or more wavelengths from said tunable filter and providing an output pulse for each particle passing through the illuminated detection volume.