Patent ID: 6028671
Filing Date: 2000-02-22
Classification: G01N

Abstract:
The system of suppressing unwanted reflections in 3D imaging system including a source of electromagnetic energy, optical elements for directing a beam of the electromagnetic energy to an object having a point of interest, means including an optical isolator for polarizing the beam of electromagnetic energy in a first rotational sense, the polarized beam of electromagnetic energy being incident upon the point of interest of the object, the object being capable of reflecting the polarized beam of electromagnetic energy to obtain reflected electromagnetic energy, and a receiver having a detector for collecting the reflected electromagnetic energy, wherein the improvement comprises:means including a polarizer for filtering the reflected electromagnetic energy wherein reflected electromagnetic energy polarized in the first rotational sense is attenuated and reflected electromagnetic energy polarized in a second rotational sense opposite to the first rotational sense is passed and wherein secondary and other even numbered reflections from locations other than the point of interest on the object are suppressed and wherein the receiver is a triangulation-based 3D receiver and wherein the reflected electromagnetic energy is polarized along major and minor axes and wherein the ratio of the minor axis to the major axis is substantially equal to 1.