Investigation On The Optimal Wavelength For Two-photon Mcroscopy In Brain Tissue

Two-photon microscopy(TPM)has been one of the most widely used fluorescent microscopy methods in biological tissue.The femtosecond laser in the near infrared(NIR)range showed better penetration in tissue due to less scattering and absorption.The method to estimate the optimal wavelength generally according to the scattering and absorption is somehow too rough considering the complex biological property and other factors that influence TPM.In this thesis,a model is developed to calculate the optimal wavelength in the NIR range for different imaging depths by involving more parameters of TPM.The calculated and experimental results show good consistence but large difference from the model with only scattering and absorption.The results presented here may therefore bring better understanding on TPM in tissue and help to develop more accurate model for the simulation of TPM.