Method and apparatus for recording three-dimensional distribution of light scattering

摘要

An apparatus is disclosed for generating data representative of a three-dimensional distribution of the light backscattering potential of a transparent or semi-transparent object such as a human eye. The apparatus includes an interferometer, both the reference beam and measurement beam of which are directed toward the object and reflected by respective reference and measurement sites thereof, such that axial motion of the object during measurement affects both beams equally. The measurement beam is raster scanned transversely across each measurement site for which data is obtained. Also, the frequency of one of the beams is shifted by a non-moving frequency shifter, such that the reflected beams combine and are modulated by a heterodyne beat frequency, which is detected when the object path difference is matched with the interferometer path difference. Because the non-moving frequency shifter can effectively generate a beat frequency of about 40 MHz, relatively rapid transverse and longitudinal scanning are facilitated.