Optical coherence tomography (OCT) with ultrahigh axial resolution was achieved by the super-contin-uum generated by coupling femtosecond pulses from a commercial Ti:sapphire laser into an air-silica microstructure fiber. The visible spectrum of the super-continuum from 450 to 700 nm centered at 540 nm can be generated. A free-space axial OCT resolution of 0.64 μm was achieved. The sensitivity of OCT system was 108 dB with incident light power 3 mW at sample,only 7dB below the theoretical limit. Subcellular OCT imaging was also demonstrated,showing great potential for biomedical application.
Photodynamic therapy (PDT) is a very effective treatment for port wine stains (PWS). To guide and assess PDT treatment, a handheld optical coherence tomography (OCT) probe was designed for real-time imaging of the PWS patient. The system uses a light source with a center wavelength of 1310 nm, -3 dB bandwidth of 90 nm and an optical power of 9 mW. The system also has a spatial resolution of 8 μm (lateral) × 7 μm (axial), an imaging rate of 4 frames per second, and a 102 dB sensitivity. We then demonstrate that the OCT imaging system can clearly distinguish between normal and PWS tissues. Therefore, the system can provide valuable guidance for PDT treatment.
WANG TianShiWANG ChengMingHUANG NaiYanZHANG JianGU YingXUE Ping
