Patent ID: 7557931

Claim:
An optical tomography method in which low coherence light emitted from a light source is divided into measuring light and reference light, the measuring light is collected by a lens system to be projected onto an object of measurement, the reflected light from the object and the reference light are multiplexed, interference light of the reflected light and reference light which have been multiplexed is detected, intensities of the reflected light in a plurality of positions in the direction of depth of the object of measurement are detected by carrying out a Fourier analysis on each channeled spectrum obtained by decomposing the detected interference light into frequency components and a tomographic image of the object is obtained on the basis of the intensity of the reflected light in each position in the direction of depth, wherein the improvement comprises the steps of stepwise changing the optical path length of the reference light thereby adjusting the optical path length of the reference light within the focusing range with respect to the object of the measuring light collected by the lens system, obtaining a plurality of pieces of data representing the intensity of the reflected light in a plurality of positions in the direction of depth each time the position of the focusing range changes, extracting data on the position in the direction of depth where the measuring light is in the focusing range out of the pieces of data representing the intensity of the reflected light, and obtaining a tomographic image on the basis of the extracted piece of data.