In vivo ultrahigh resolution optical coherence tomography using a Kerr-lens modelocked Ti:Al/sub 2/O/sub 3/ laser

Summary form only given. Over the past few years, optical coherence tomography (OCT) has been extensively evaluated as a possible diagnostic tool in a variety of medical fields, demonstrating its feasibility as a high speed, non-invasive, high resolution in vivo and in situ imaging modality with the possibility of being easily implemented into different medical diagnostic instruments; e.g., catheters, microscopes, as well as ophthalmoscopes. We demonstrate an ultrahigh, subcellular level resolution OCT system for in vivo and in vitro imaging. It uses a Kerr-lens mode-locked Ti:sapphire laser that emits pulses as short as 5.5 fs with bandwidths up to 350 nm centred at 800 nm with an average power of up to 150 mW, due to broadband controlled dispersion and high reflectivity enabled by low-dispersion prisms and special designed double chirped mirrors. The output spectrum can be shaped by changing the prisms insertions (P1, P2) or by alteration of the prism separation. Appropriate single mode fibers, special broad bandwidth, wavelength flattened 3 dB fiber coupler, as well as special achromatic and catadioptric objectives are used to maintain this ultrabroad bandwidth to achieve subcellular level resolution.