Steven E Pratt

US Patent:

6885440, Apr 26, 2005

Filed:

Nov 7, 2002

Appl. No.:

10/289266

Inventors:

David B. Silcott - Reisterstown MD, US
Greg A. Tilley - Monkton MD, US
Brian R. Whitman - Towson MD, US
Steven J. Pratt - Baltimore MD, US

Assignee:

S31, LLC - Owings Mills MD

International Classification:

G01N021/00
G21G005/00

US Classification:

356 73, 356343, 356344, 2504921, 436172

Abstract:

A continuous wave laser excites a biological particle. Detection channels are created to detect light scattered by the biological particle, and to detect any auto-fluorescence emitted by the biological particle. Additional channels can also detect light emitted by auto-fluorescence of the biological particle when simultaneously excited by light at harmonics of the laser's fundamental wavelength. The biological particle is identified using Mie scattering and auto-fluorescence. Ratio-metric calculations generated by calculating ratios of detected peak heights or integrated pulse values in the channels provides additional information for identifying and classifying the biological particle. A warning or alert can be provided if the identified biological particle is a particle of interest.