Patent ID: 8269639
Filing Date: 2012-09-18
Classification: G01N,G08B

Abstract:
1. A particle detector for determining a presence of particles in a fluid sample, the detector comprising: a first light source configured to illuminate the sample in a first illumination with light of a first wavelength; a second light source configured to illuminate the sample in a second illumination with light of a second wavelength; sensor means configured to obtain a first response signal indicative of the first illumination from light scattered off of particles in the sample and to obtain a second response signal indicative of the second illumination from light scattered off of particles in the sample; and logic means configured to receive the first and second signals and to provide a predetermined threshold for comparison of the first and second signals, the threshold being a predetermined ratio of signals indicative of the first and second illuminations, said logic means being configured for basing the comparison upon a subtraction of the first signal from the second signal.