Patent ID: 7982880

Claim:
An optical image measurement device comprising: a light source configured to emit a low-coherence light; an interference-light generator configured to generate a interference light by splitting the emitted low-coherence light into a signal light heading toward a measurement subject and a reference light heading toward a reference object, and superimposing the signal light passed through the measurement subject and the reference light passed through the reference object; a changer configured to change a difference in optical path length between the signal light and the reference light; a detector configured to detect the generated interference light; an image forming part configured to form an image within a predetermined frame defined by a length in the depth-wise direction of the measurement object based on the result of the detection by the detector; a determination part configured to determine a positional relation between a predetermined depth position of the measurement subject in the formed image and a specific position within the predetermined frame; and a controller configured to control the changer to change the difference in optical path length so that a partial image corresponding to a predetermined depth position of the measurement subject in the formed image is placed in a specific position within the predetermined frame based on the determined positional relation, wherein the predetermined frame indicates a target region of forming the image based on the detection of the interference light; and the specific position within the frame indicates a region with favorable measurement sensitivity for the imaging based on the detection of the interference light.