COMPOUND OPTICAL FLOW CELLS AND METHOD OF MANUFACTURE AND USE

摘要

An improved optical flow cell adapted for use in a flow cytometer for differentiating formed bodies (e.g., blood cells) in liquid suspensions. Preferably manufactured by assembling, aligning, and optically joining at least two elements made from transparent material, the improved flow cell has a seamless internal flow channel of preferably non-circular cross-section in a cylindrical first element through which prepared samples can be metered and an independent second element having an external envelope suited to acquisition of optical parameters from formed bodies in such suspensions, the second element being conforming and alignable to the first element so that non-axisymmetric refractive effects on optical characterizing parameters of formed bodies passing through the flow channel in the first element may be minimized before the two elements are optically joined and fixed in working spatial relationship.

主权项

1. A method for making a transparent compound optical flow cell of the type used to characterize formed bodies passing through the flow cell, the optical flow cell having formed therein a rectilinear internal flow channel, the method comprising the steps of:
providing a cylindrical monolithic preform comprising a thick-wall glass tube having an axially-extending channel therethrough and a transition temperature, the channel comprising a substantially uniform original cross-section of a desired shape; heating the preform to a predetermined temperature above the transition temperature of the glass tube; axially drawing the preform at a controlled rate, for a controlled time, and at a constant angular orientation, to achieve a desired reduced cross-sectional area of the axially-extending channel; providing an optical element, the optical element comprising a conforming surface that conforms to a segment of the drawn preform, and an exterior non-cylindrical envelope of predetermined form and orientation relative to the conforming surface; assembling the optical element on the segment so that the optical element and the segment are in a desired spatial relationship, and the conforming surface of the optical element is positioned so as to minimize non-axisymmetric refractive effects on optical characterizing parameters acquired from formed bodies passing through the reduced cross-sectional area of the axially-extending channel; and optically joining the optical element to the segment so as to fix the optical element and the segment in the desired spatial relationship.