Inline optical coherence tomography (OCT) has proven to be an ideal feedback mechanism for real-time depth control of high-power ablation lasers. This has found use in industrial laser ablation applications, but it has the potential to truly change the use of laser ablation in medicine. Previously, we have presented a novel design that is able to place the OCT beam ( λc = 1310nm) coaxially with the beam of a high-powered fiber laser (λ = 1064nm, Pavg=10W, Ppeak = 1kW) without the need of a dichroic mirror on the output stage. This design successfully demonstrated real-time ablation depth feedback. Development of this design was continued and further refinements have been made to improve performance and form factor, with the ultimate goal being to create a compact, low-cost, high-precision laser scalpel to be used for various surgical osteotomies. We present an improved design that, unlike before, removes the need for bulk optics in the entire system other than a single collimator and doublet lens on the output. Strategies for dispersion mismatch compensation will be discussed to optimize resolution of OCT feedback. Initial results for depth-controlled ablation of tissue is presented.
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