PROBLEM TO BE SOLVED: To make the difference in a cross-sectional image produced by the optical system in a tomographic imaging device inconspicuous in the tomographic imaging device for acquiring the cross-sectional image from the signals of a plurality of synthetic lights obtained using a plurality of measuring lights.SOLUTION: The tomographic imaging device is constituted so as to synthesize a plurality of return lights, which are obtained by irradiating an object to be inspected with a plurality of measuring lights, and reference light to acquire the cross-sectional image of the object to be inspected from a plurality of the obtained synthetic lights and has a sensor for detecting a plurality of the synthetic lights to acquire the signals of a plurality of the synthetic lights, an acquiring means for acquiring the distribution characteristics of a plurality of the respective synthetic lights on the sensor, and a means for forming the cross-sectional image of the object to be inspected from the distribution characteristics and the signals of a plurality of the synthetic lights.
