Patent ID: 7333206
Filing Date: 2008-02-19
Classification: G01N

Abstract:
1. An apparatus for measuring light scatter loss from a test piece, the apparatus comprising: a light source to provide an input beam; an optical cavity including the test piece and at least one mirror disposed along a path, the cavity being configured to receive the input beam, to circulate a beam within the cavity as a circulating beam, and to produce an output beam, the circulating beam undergoing a progressive diffusion about the path; and a light detector to provide an output signal based on the intensity of the output beam, the output signal having an initial slope determining a first saturation value, the output signal having a second saturation value, wherein the initial slope is determined during a first detection period and the second saturation value is determined during a second detection time after the first detection period, and wherein the difference between the first saturation value and the second saturation value provides a scatter loss measurement.