Patent ID: 8675194
Filing Date: 2014-03-18
Classification: G01J,G01N

Abstract:
1. An apparatus for measuring retroreflectivity of materials, comprising: an LED light source; a spectrometer; a first optical path configured to direct an illumination beam from the LED light source to illuminate with collimated light, a material to be tested; and a second optical path to direct a retroreflected beam from the material to the spectrometer, wherein the illumination optical path further comprises an annular aperture to collect the illumination beam, and wherein the second optical path comprises: a focusing lens to collect the retroreflected beam from the material to be tested; a beamsplitter to reflect a portion of the collected retroreflected beam and to transmit the portion of the collected retroreflected beam that is not reflected by the beamsplitter; a receiver aperture to collect the transmitted portion of the beam; and an optical fiber to transfer the light from the receiver aperture to the spectrometer.