Patent ID: 9019484
Filing Date: 2015-04-28
Classification: G01B,G01N

Abstract:
1. A spectral reflectance system, comprising: a first light source that illuminates a film with first illumination having a first angle of incidence that is approximately normal to the film, wherein the film covers at least a portion of a first side of a sample; a transmittance collection fiber that collects transmitted light of the first illumination transmitted by the film; a first collection fiber that collects reflected light of the first illumination reflected by the film; a second light source that illuminates the film with second illumination having a second angle of incidence that is approximately non-normal to the film; a second collection fiber that collects reflected light of the second illumination reflected by the film; and a processor executing a model-free application that determines at least one property of the film using data of the normal-incidence reflected light, the normal-incidence transmitted light, and the non-normal-incidence reflected light.