Patent ID: 6466318
Filing Date: 2002-10-15
Classification: G01N

Abstract:
A light scattering instrument for measuring total particle volume and total particle area at the same time for particles suspended in water, comprising:a. a sample void where water containing particles is admitted; b. beside the sample void, a source of a beam of light directed at the sample void; and c. on an opposite side of the sample void, i. a first light power detector with an active surface shape configured to receive forward scattered light and produce an output signal which is proportional to total particle area at varying total particle areas, the active surface shape of the first light power detector intercepting less than an entire annulus at each distance from an axis of the beam, the portion of an annulus intercepted increasing at an increasing rate with distance from the axis of the beam; and ii. a second light power detector with an active surface shape configured to receive forward scattered light and produce an output signal which is proportional to total particle volume at varying total particle volumes, the active surface shape of the second light power detector intercepting less than an entire annulus at each distance from an axis of the beam, the portion of an annulus intercepted decreasing with distance from the axis of the beam.