Applying Nonlinear Laser Microscopy to Melanoma Diagnosis and Renaissance Art Imaging

Our lab developed femtosecond laser pulse shaping technologies two decades ago; today we know that the "killer application" is clinical imaging, where we can access intrinsic molecular nonlinear signatures that were not previously observable in tissue, such as excited state absorption, ground state depletion, and cross phase modulation.  Applications to imaging hemoglobins and melanins in tissue to detect and assess cancer will be highlighted.  We have shown that the same methods can be applied to cultural heritage imaging; this method generates noninvasive 3-d images with modest power and chemical specificity.  Demonstrated applications include the geo-sourcing of the historically important pigment lapis lazuli, imaging of several cross sections from Renaissance era paintings, completely non-destructive depth imaging on an intact 14^th century painting (The Crucifixion by Puccio Capanna), differentiation of earth pigments to infer pottery firing conditions, analysis of parchment samples, and investigation of photodegradation. We show that this method provides microscopic information valuable for dating and sourcing pigments, elucidating methods of preparation, and profiling degradation products.  We will compare and constrast the challenges in biological tissue imaging and cultural heritage imaging, to highlight the opportunities to develop synergies.