Optical tomography apparatus

An optical tomography apparatus, comprising:

• a light source, for emitting a low coherence light beam;
• dividing means, for dividing the low coherence light beam into a measuring light beam and a reference light beam;
• an irradiating optical system, for irradiating the measuring light beam onto a measurement target;
• optical path length changing means, for changing the optical path length of one of the reference light beam and the measuring light beam;
• multiplexing means, for multiplexing a reflected light beam, which is the measuring light beam reflected by the measurement target, and the reference light beam, to obtain a coherent light beam;
• and
• image obtaining means, for detecting the intensity of the reflected light beam at a plurality of depth positions of the measurement target, at which the optical path length of the reference light beam and the sum of the optical path lengths of the measuring light beam and the reflected light beam substantially match, based on the optical intensity of the multiplexed coherent light beam, and for obtaining tomographic images of the measurement target, based on the intensities at each of the depth positions;
• a central wavelength λc and a full width at half maximum spectrum Δλ of the reference light beam and the reflected light beam satisfying the following conditions;
• λc2/Δλ≦23
• λc+(Δλ/2)≦1.2 μm
• λc−(Δλ/2)≧0.98 μm.