We report on phase-dispersion optical tomography, a new imaging technique based on phase measurements using low-coherence interferometry. The technique simultaneously probes the target with fundamental and second-harmonic light and interferometrically measures the relative phase shift of the backscattered light fields. This phase change can arise either from reflection at an interface within a sample or from bulk refraction. We show that this highly sensitive (~5°) phase technique can complement optical coherence tomography, which measures electric field amplitude, by revealing otherwise undetectable dispersive variations in the sample.
© 2001 Optical Society of America
(050.5080) Diffraction and gratings : Phase shift
(110.4500) Imaging systems : Optical coherence tomography
(180.3170) Microscopy : Interference microscopy
(240.6700) Optics at surfaces : Surfaces
Changhuei Yang, Adam Wax, Ramachandra R. Dasari, and Michael S. Feld, "Phase-dispersion optical tomography," Opt. Lett. 26, 686-688 (2001)