Investigation of laser systems for 3D endomicroscopy using coherent fiber bundles

该项目的目的是一种新型内窥镜技术的基础研究。柔性内窥镜，其最小直径被期望用于通过具有关键的整体访问的光进行感测和致动。微创3D成像与生物医学和生产技术相关。此外，光纤内窥镜在光遗传学和3D打印技术中也很重要。现有的内窥镜都是基于光强度的评估，并使用成像光学器件。这使得它们不适用于许多应用。该项目的目的是评估光的复相量，而不是使用成像光学。因此，光纤成像波导用于传输光的3D信息（空间强度和相位分布）。这使得柔性内窥镜能够实现，其直径仅受光纤限制。挑战是在光纤传输期间校准光场扰动，而无需访问两个光纤刻面和原位。校准技术，使强大的光纤弯曲，并使用集成的光纤反射器，应进行调查。标定信息和目标信息叠加。飞秒激光脉冲应用于信息解复用。这将使3D结构的测量以及光遗传细胞刺激成为可能。应探索接收波前整形，以便在没有自适应光学器件的情况下进行快速单次激发3D成像，并具有高数据速率。关于新型内窥镜技术的致动和传感特性的研究将产生新的见解，特别是在生物光子学中具有很高的兴趣。

The aim of the project is the fundamental research of a novel endoscopic technique. Flexible endoscopes, witch minimal diameters are desired for sensing and actuating by light with key whole access. Minimally invasive 3D imaging is relevant in biomedicine and production technique. Additionally, fiber based endoscope important in optogenetics and 3D printing techniques. Existing endoscope are based on the evaluation of light intensity and use imaging optics. This makes them inapplicable to many applications. The aim of project is to evaluate the complex phasor of light instead of using imaging optics. Thus, fiber optic imaging waveguides are employed for transmitting 3D information of light (spatial intensity and phase distribution). This enables flexible endoscopes, which are limited in diameter only by the fiber. The challenge is to calibrate the light field disturbance during transmission of the fiber, without access to bot fiber facets and in-situ. A calibration technique, which enables strong fiber bending and uses an integrated fiber reflector, shall be investigated. The information of calibration and object are superposed. Femtosecond laser pulses shall be used for information demultiplexing. This will enable measurements of 3D structures and as well as optogenetic cell stimulation. Receiving wave front shaping shall be explored for a fast single shot 3D imaging without adaptive optics with high data rate. The investigations regarding the properties for actuation and sensing with the novel endoscope technique will yield exiting new insights, which are of high interest especially in biophotonics.