Patent ID: 6175750
Filing Date: 2001-01-16
Classification: G01J

Abstract:
An apparatus for analysis of an object by use of reflected spectral imaging, comprising:(a) a light source for illuminating the object;(b) an optical filter disposed in the light path between said light source and the object and which, when illuminated, projects onto the object an image comprising a plurality of areas, each having a different known optical density;(c) a first polarizer for polarizing light from said light source;(d) an image capturing module for capturing an image reflected from the object at a depth less than a multiple scattering length, said reflected image traveling along a reflected light path between the object and said image capturing means;(e) a second polarizer disposed in said reflected light path between the object and said image capturing means, wherein a plane of polarization of said second polarizer is oriented approximately 90.degree. relative to a plane of polarization of said first polarizer;(f) an image correcting and analyzing module coupled to said image capturing module for correcting and analyzing said reflected image; and(g) a calibration module for measuring the intensity of the light reflected from different points of the image projected by said optical filter onto said object, mapping the measurements to the optical densities known to be present at said projected image, and calibrating the apparatus using the mapping.