MULTIPHOTON SPECTROSCOPY THROUGH OPTICAL SINGLE MODE FIBERS

组织中的自体荧光可以作为诊断工具 光动力疗法(如癌症)。多光子激发； 近红外波长范围；可用于自发荧光 在生物组织最透明的地方成像。然而， 侵彻深度仍然有限(约200？m)，甚至更成问题 用于自体荧光检测。将单模光纤用于两者 同时激发和检测(多光子内窥镜)提供 这是一个极好的解决方案。因此，对该问题的初步研究。 飞秒激光脉冲(810-980 nm)的展宽效应 研究了光纤耦合效率与强度的关系。 出去。此外，检测到的荧光(荧光素，~200m； 溶解在水中)通过相同的纤维在 频域。依赖功率的测量揭示了真正的 双光子荧光。

Autofluorescence in tissues can be used as a diagnostic tool in photodynamic therapy (e.g. for cancer). Multiphoton excitation; i.e. near infrared wavelength range; can be used for autofluorescence imaging where biological tissues are most transparent. However, the penetration depth is still limited (~200 ?m) and even more problematic for autofluorescence detection. Using single-mode fiber for both excitation and detection simultaneously (mutliphoton endoscopy) offers an excellent solution. Therefore, preliminary studies on the broadening effects of femtosecond laser pulses (810-980 nm) and the intensity-dependence of the fiber coupling efficiency has been carried out. Furthermore, the detected fluorescence (of fluorescein, ~200 ?M; dissolved in water) through the same fiber has been resolved in the frequency domain. Power-dependent measurements reveal a genuine two-photon fluorescence.