PROBLEM TO BE SOLVED: To accurately acquire a projection amount of an OCT (Optical Coherence Tomography) probe with a simple configuration without causing increase of a diameter of an endoscope insertion part.SOLUTION: Measurement light L1 is applied on a measurement target S from an optical lens 628 while performing linear scanning by the measurement light L1 applied from the optical lens 628 in the long axis direction of the OCT probe 600 without performing rotary scanning around the long axis of the OCT probe 600, and return light L3 from the measurement target S is obtained by the optical lens 628. A linear tomographic image in the long axis direction of the OCT probe 600 is acquired based on the return light L3 obtained by the optical lens 628, and the projection amount of the OCT probe 600 is calculated by detecting timing when the linear tomographic image changes from a tomographic area to a non-tomographic area (or reversely thereto).COPYRIGHT: (C)2012,JPO&INPIT【課題】内視鏡挿入部の太径化を招くことなく簡易な構成でOCTプローブの突出量を正確に把握可能とする。【解決手段】光学レンズ628から照射される測定光L1をOCTプローブ600の長軸周りに回転走査することなくOCTプローブ600の長軸方向にリニア走査しながら、光学レンズ628から測定光L1を測定対象Sに照射するとともに、該測定対象Sからの戻り光L3を光学レンズ628で得る。そして、光学レンズ628で得られた戻り光L3に基づいて、OCTプローブ600の長軸方向のリニア断層画像を取得し、該リニア断層画像が断層領域から非断層領域(又はその逆)に変化するタイミングを検出することによりOCTプローブ600の突出量を算出する。【選択図】図5
