Patent ID: 7773208

Claim:
Device for measuring characterization by reflectometry of a sample with a reflective surface which successively comprises: a light source that emits a light beam, optics to collect and focus the light beam through the device, the optics image the light beam onto both the surface of the sample and onto at least one photodetector, a spectral or temporal disperser, spatial or temporal modules to filter the light beam in order to reduce an acquisition noise, a spectral or temporal separator to obtain two different signals, a focusing optics which is oversized compared with the light beam, a camera to visualize a spot image on the reflective surface of the sample, wherein the spectral or temporal disperser is a monochromator, wherein the acquisition noise is electronic noise, optical noise, or both, wherein the two different signals are a reference signal and a measurement signal that do not interfere, both signals being a reference channel and a sample channel, wherein at least one of the optics is large in size compared with the light beam, and wherein the at least one photodetector is connected to comment and acquisition units.