We demonstrate dispersion compensation by using a dispersion shifted fiber (zero dispersion at a wavelength of 1550 nm) in an optical-frequency domain imaging (OFDI) - optical coherence tomography (OCT) system for tooth imaging. In the system, we use a tunable laser diode operating in the 1550 nm wavelength region (1533-1573 nm) as a light source, because we can expect a smaller absorption coefficient for the enamel layer of a tooth than with a 1300 nm light source. This simple and cost-effective method provides an axial resolution of 27 &mgr;m in air, which is the theoretically expected value, although the value is 36 &mgr;m without compensation. By measuring an extracted human tooth with compensation, we also confirm the realization of greatly improved contrast at the boundary between the enamel and dentin layers. This compensation technique might prove even more effective if we use a light source with a wider wavelength range.

Date Published: 7 February 2007
PDF: 6 pages
Proc. SPIE 6429, Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI, 642926 (7 February 2007); doi: 10.1117/12.702954

Published in SPIE Proceedings Vol. 6429:
Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI
James G. Fujimoto; Joseph A. Izatt; Valery V. Tuchin, Editor(s)