Patent ID: 7468789

Claim:
A cytometer system comprising: a liquid input manifold including: a sample bore having a first end for receiving a sample liquid therein and a second end for discharging the received sample liquid; arid a pre-injection chamber surrounding the sample bore adjacent the first end thereof in spaced coaxial relation, said pre-injection chamber for receiving sheath liquid therein; an injection chamber surrounding the sample bore in spaced coaxial relation, said injection chamber having a first end for receiving sheath liquid therein from said pre-injection chamber and a second end for discharging the received sheath liquid adjacent the second end of the sample bore, said injection chamber having a cross section that gradually decreases in area toward the second end thereof, wherein, where said pre-injection chamber intersects the first end of the injection chamber, said pre-injection chamber has a larger cross-sectional area than the first end of the injection chamber whereupon sheath liquid received in the pre-injection chamber gradually drains into the injection chamber; and an elongated cuvette including a central bore having a first end positioned for receiving from the input manifold a flow of sample liquid surrounded by a flow of sheath liquid and a second end for discharging said received liquids, the first end of said central bore having a cross section that gradually diminishes in diameter with increasing distance from said first end, said gradually diminishing cross section diameter of said central bore terminating in a length of said central bore that extends toward the second end of said central bore.