Adaptive lasersystems for biomedical applications

Motivation

MST develops and investigates novel adaptive optical systems for biomedical applications based on various kinds of spatial light modulators. Some applications aim for fast and flexible, targeted light delivery in 3D optogenetic stimulation of human induced pluripotent stem-cells (hIPS), achieving kHz rates. Others aim to transfer light-information through strongly scattering beam paths like 400 µm skull tissue using digital optical phase conjugation techniques, important for deep-tissue applications. One common question for adaptive optics is: what to display on the spatial light modulator to achieve a certain target? Beside well-known iterative and guide-star approaches we constantly develop novel calibration techniques. Using an in-situ calibration of a multi-core fibre transforms the fiber to a remote lensless endoscopes usable for scanning microscopy and tomographic refractive index measurements of cells. Fast scanning and reduction of specimen induced aberrations using special adaptive lenses enables mechanical motion free smart microscopes, for measurement of the Zebrafish thyroid glands. 

In this field we have the following projects:

• Tomographic refractive index measurement using Adaptive fiber-optical cell ROTation (TAROT)
• Laser System for Optogenetic Stimulation for the Subcellular Investigation
  of neural Networks

• Aberration correction for real-time measurements in adaptive confocal microscopy

• Adaptive laser systems with wave front correction and phase conjugation for fluid flow measurements compensating refractive index effects

• Optogenetic Modeling of Arrhythmias Using Holographic Light Stimulation