Patent ID: 9693839
Date: 2017-07-04
CPC Classifications: A61B,A61C,G01B,G02B

Claim:
1. An apparatus for dental imaging, the apparatus comprising: an illumination module for generating a light beam travelling an optical path, the light beam having a wavelength; a probe head comprising a light-guiding part having, an optics system to direct the light beam along the optical path to enter the light guiding part via the entrance face, travel along the optical path extending between the entrance face and the exit face, and exits the light-guiding part via the exit face, said first and second retardances being in amounts such that the light-guiding part provides a total retardance of an odd multiple of the quarter of the wavelength along the optical path extending from the entrance face to the exit face, wherein each of the first retardance, the second retardance, and the total retardance is a retardance to a first polarization component relative to a second polarization component of the light beam traveling along the optical path.