Patent ID: 6738136
Filing Date: 2004-05-18
Classification: G01J,G01N

Abstract:
A system for measuring characteristics of a sample, including:a light source for generating a beam of light which is directed toward a sample; a mirror which can be moved between a first position and a second position, wherein in the first position the mirror is positioned between the light source and the sample such that light generated by the light source is reflected off the mirror and transmitted through a first path, wherein the first path consists of a reflection path, wherein in the second position the mirror is positioned such that it is not between the light source and the sample, and light generated by the light source is reflected off the sample and transmitted through the reflection path; a detector coupled to the reflection path which generates a monitor signal in response to receiving light reflected from the mirror, and generates a measurement signal in response to light reflected from the sample; and a beam splitter positioned between the light source and the sample, wherein light from the light source is incident on the beam splitter and directed from the beam splitter toward the sample.