Cytometer with automatic continuous alignment correction

摘要

A system and method for performing flow cytometry is disclosed wherein the alignment of the light source with respect to the sensing region of the fluid stream is continuously controlled using a feedback control loop. An imaging apparatus is provided that images the system along the optical axis, between the field stop and the sensing region. In an embodiment, the cytometer includes a field stop having an H-shaped aperture and light diverters over the ends of the aperture that divert a portion of the light to peripheral detectors.

主权项

1. A flow cytometry system operable to examine a fluid stream having particles suspended therein, the cytometry system comprising:
a light source focused on a sensing region in the fluid stream; an objective positioned to receive light from the sensing region; a lens positioned to receive light from the objective, wherein the lens and objective define an optical axis; a field stop having an aperture; a beam splitter that is positioned between the lens and the field stop that intersects the optical axis at an angle; an imaging device positioned to generate images from light received from the beam splitter, the beam splitter and imaging device being oriented such that the generated images are along the optical axis; an XY stage defining a support surface that is precisely controllable in at least two orthogonal directions, wherein the XY stage supports an optical element that determines the alignment of the light source with respect to the sensing region; a computing device that receives the images generated by the imaging device and calculates from the images at least one parameter that characterizes the alignment of the light source with the sensing region, wherein the at least one calculated parameter is used to generate control signals that are transmitted to the XY stage such that a desired alignment of the light source with the sensing region is maintained.