FLOW CYTOMETRY OPTICS

摘要

High numerical aperture collection optics for particle analyzers may include an ellipsoidal reflector or an ellipsoidal reflector in combination with a spherical reflector, and may efficiently collect light scattered or emitted by particles in a sample stream and then couple that collected light into a lower numerical aperture portion of the instrument's optical detection system, such as into an optical fiber for example. The reflectors may be integrated with a flow cell through which the sample stream passes, or may be separate components arranged around a flow cell or, in instruments not employing a flow cell, arranged around a sample stream in air. Refractive beam steering optics may allow multiple closely spaced excitation beams to be directed into the sample stream at low angles of incidence. The collection optics and refractive beam steering optics may be employed separately or in combination with each other.

主权项

1. A particle analyzer comprising:
an ellipsoidal reflector having a shape characterized by lengths of major and minor axes of a defining ellipse and having conjugate foci F1 and F2 located on the major axis, with F1 in a flow path for a stream of particles; one or more light sources configured to provide one or more excitation light beams directed to intersect the stream of particles at or approximately at F1, thereby exciting fluorescence from the particles; and a spherical reflector having its center of curvature coincident or approximately coincident with F1; wherein at least a portion of fluorescence emitted toward the ellipsoidal reflector is focused by the ellipsoidal reflector to one or more locations at or near F2, at least a portion of fluorescence emitted toward the spherical reflector is retro-reflected by the spherical reflector toward the ellipsoidal reflector which focuses the retro-reflected fluorescence to the one or more locations at or near F2, and the ratio of the major and minor axes of the ellipse defining the shape of the ellipsoidal reflector is greater than or equal to about 1.2.