Patent ID: 8346348

Claim:
An optical coherent cross-sectional image forming apparatus in which light outputted from a light source is divided into a measurement light and a reference light inside the apparatus and in which a cross-sectional image is formed based on a coherent light obtained from reflected light, acquired when the measurement light emitted toward a biological tissue through a probe inserted into a body lumen is reflected, and the reference light, the apparatus comprising: a transmitting and receiving unit at a distal end portion of the probe, the transmitting and receiving unit emitting the measurement light and also receiving the reflected light, the transmitting and receiving unit being axially movable relative to a catheter sheath during operation of the apparatus; a scanning drive unit connected to the transmitting and receiving unit to rotate and axially move the transmitting and receiving unit; generating and holding means for generating data, corresponding to the cross-sectional image, using the coherent light between the reflected light obtained through the transmitting and receiving unit and the reference light, and for holding the data; means for detecting, through use of the data held by the generating and holding means, that the transmitting and receiving unit has entered inside the catheter sheath during the axial movement; and a controller for stopping at least a portion of an operational aspect of the apparatus, from when the data corresponding to the cross-sectional image is generated to when the data is held, whenever the means for detecting detects that the transmitting and receiving unit has entered the catheter sheath.