Patent ID: 6583866
Filing Date: 2003-06-24
Classification: G01J

Abstract:
A method for making spectral measurements with a reduced optical path length, diffraction grating-based, spectrometer device, comprising the steps of:providing light to a diffraction grating, wherein the diffraction grating requires a first optical path length from the diffraction grating for a first predetermined spectral resolution of spectral measurement; providing a plurality of filter elements and a plurality of optical sensors, wherein the plurality of filter elements are positioned in an optical path between the diffraction grating and the plurality of optical sensors; receiving diffracted light from the diffraction grating with the plurality of optical sensors, wherein the light is incident upon and selectively transmitted through a plurality of the filter elements prior to being received by the plurality of optical sensors; wherein spectral characteristics of the light provided to the diffraction grating are measured; wherein the filter elements/optical sensors are positioned to define a second optical path length from the diffraction grating, wherein the second optical path length is less than the first optical path length, wherein the spectral characteristics of the light provided to the diffraction grating are measured in accordance with the first predetermined spectral resolution with a reduced optical path length; wherein the light is provided to a material or object by a probe and light returned from the material or object is provided to the diffraction grating, wherein the method further comprises the step of providing light received from the material or object to second optical sensors, wherein the second optical sensors provide data indicative of a height or angle of the probe with respect to the material or object, provide data indicative of an optical value measurement of the material or object, or provide data indicative of translucence, gloss, opalescence, texture or other optical characteristics of the material or object.