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Optical imaging of hard and soft dental tissues using discretely swept optical frequency domain reflectometry optical coherence tomography at wavelengths from 1560 to 1600 nm.

We have been developing a Mach-Zehnder type of optical frequency domain reflectometry optical coherence tomography (OFDR-OCT) that uses discretely swept superstructure-grating distributed Bragg- reflector (SSG-DBR) lasers developed for telecommunication fields and has a 12-mm-depth range. We report images obtained with L-band (1560 to 1600 nm) and C-band (1529 to 1568 nm) SSG-DBR sources at 0.5 micros/step, which is 20 times faster than the scanning speed used to obtain the images we reported previously. Despite the faster scanning, we obtain good OCT images of both hard and soft dental tissues in vitro and in vivo.