Patent ID: 8269968

Claim:
A device for evaluating a state of wetting of a surface, the device comprising: at least one emitter able to emit at least one light beam which is incident in a direction of a surface, the surface being able to at least partly reflect the beam; a single means for receiving the beam reflected by the surface; means for polarisation comprising at least one first polarisation zone and one second polarisation zone capable of polarising a first part and a second part of the beam in a first polarisation direction and a second polarisation direction respectively, the first part and the second part of the beam having a first wavelength and a second wavelength respectively, the second wavelength being different from the first wavelength, and the means for polarisation being located between the emitter and the surface under analysis; means for recombining the first part and the second part of the polarized beam in the first polarisation direction and the second polarisation direction respectively in only one beam, the means for recombination being located between the emitter and the surface; and means for calculation capable of calculating a polarisation ratio between the polarisations of the first part of the reflected beam and the second part of the reflected beam in order to evaluate the state of wetting of the surface.