Patent ID: 7142307
Filing Date: 2006-11-28
Classification: G01N

Abstract:
1. A method for improving optical interactance measurements comprising the steps of: passing illumination along a plurality of different transmission paths through an interior portion of a material having a characteristic to be measured; defining each of said paths by corresponding and separated surface areas on said material, one of said surface areas for passing illumination into said material and the second of said surface areas for passing transmitted illumination from said material for detection, at least one of said surface areas of each of said paths being extended in length at substantially constant spacing from the other surface area of said each of said paths, the total length of said extended surface area of said each of said paths being substantially greater than the distance separating said corresponding and separated surface areas defining said each of said paths; providing optical directionality for radiation passing through at least one of said extended surface areas by orienting the optical axes at the respective probe surface area at an angle with respect to the surface of said material and generally towards the said corresponding and separated surface area on said material; sensing a plurality of independent signals developed at the same time or in rapid sequence representing optical information obtained from within said material in response to said illumination passing along said different paths, each independent signal corresponding to a particular path; and processing said signals in accordance with appropriate modeling techniques to determine qualitative or quantitative characteristics of the material.