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

该项目的目的是对一种新的内窥镜技术进行基础研究。灵活的内窥镜，其直径最小，用于感测和通过关键的整体通道的光驱动。微创三维成像技术与生物医学和生产技术密切相关。此外，光纤内窥镜在光遗传学和3D打印技术中具有重要意义。现有的内窥镜都是基于对光强度的评估，并使用成像光学。这使得它们不适用于许多应用程序。该项目的目的是评估光的复杂相量，而不是使用成像光学。因此，光纤成像波导被用于传输光的3D信息(空间强度和相位分布)。这使得直径仅受光纤限制的柔性内窥镜成为可能。挑战是校准光纤传输过程中的光场干扰，而不需要进入BOT光纤小面和现场。应研究一种能够实现强光纤弯曲并使用集成光纤反射器的校准技术。将标定信息和目标信息叠加在一起。信息解复用应采用飞秒激光脉冲。这将使测量3D结构以及光遗传细胞刺激成为可能。为实现无自适应光学、高数据率的快速单炮三维成像，需要探索接收波前整形。利用新的内窥镜技术对驱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方面。

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.