Holographic Stimulation Platform for Optogenetics
The stimulation platform is built around two ferroelectric spatial light modulators that enable fast, arbitrary 3D light shaping within the sample volume. Two separate beam paths allow for simultaneous illumination of the sample with multiple wavelengths, which can be fiber-coupled to the platform as needed. Currently, the platform offers 488 nm and 589 nm light, e.g., for the activation of the opsins ChR2 or Chrimson as well as eNpHR. Light patterns in the sample plane include, for example, multiple foci as well as homogeneous or graded patterns. The field of view can be adjusted as needed, for example, to accommodate electrophysiology readout devices such as multi-electrode arrays.
Our optogenetic stimulation platform consisting of an inverted microscope and adaptive stimulation optics
- 488 nm laser diode suitable for ChR2 activation
- Ferroelectric spatial light modulator (Forth Dimension Displays) for displaying Full HD computer-generated holograms
- Up to 1.7 kHz frame rate for fast kinetics
- Multiple simultaneous spot stimulation at single-cell resolution
- Lateral and axial scanning without moving parts—cellular lateral resolution with a long working distance (>30 mm)
- Light source easily interchangeable for different (color) channels
- GUI for calibration and stimulation protocols
System parameters at a glance
Exemplary Applications at MST
Closed-loop control of human cardiomyocyte contractions
Here, we have demonstrated closed-loop, all-optical, label-free control of the contractions of in vitro cultures of human induced pluripotent stem cell-derived cardiomyocytes.
Optogenetic tracking of neuronal signaling pathways
Here, we used the platform to track signaling pathways in developing random networks of human induced pluripotent stem cell-derived excitatory neurons by holographically stimulating individual neurons and tracking the resulting action potentials using a multi-electrode array.
Related publications
R. Wendland, F. Schmieder, M.A. Sikandar, F.P. Knüppel, W.-H. Zimmermann, O. Bergmann, L. Büttner, J.W. Czarske, “All-optical closed-loop control of human cardiomyocyte networks exploiting holographic optogenetics,” Nat. Comm. Eng. 5, 159 (2026)
https://doi.org/10.1038/s44172-026-00779-1
R. Wendland, F. Schmieder, M. Sikandar, W.-H. Zimmermann, O. Bergmann, J. Czarske, L. Büttner, “Real-time optogenetic control of excitation wavefronts in human cardiomyocytes using holographic one- and two-photon stimulation,” SPIE Photonics West, 13836-7, San Francisco, USA (Jan. 18, 2026)
L. Büttner, R. Wendland, F. Schmieder, M. Sikandar, W.-H. Zimmermann, O. Bergmann, J. Czarske, “Label-Free Sensing and Real-Time Holographic Optogenetic Control of Cardiac Excitation Wavefronts,” presentation FM1B.2, Frontiers in Optics, Denver, Colorado, USA, (Oct. 26–30, 2025)
F. Schmieder, L. Büttner, A.T. Pierce, W. Derks, O. Bergmann, J.W. Czarske, “Single-cell investigation of excitation wavefront propagation in in vitro human induced cardiomyocytes using a digital holographic stimulation system,” SPIE Photonics West, San Francisco, USA (January 27, 2024)
F. Schmieder, L. Büttner, W. Derks, O. Bergmann, J. Czarske, “Simultaneous optogenetic stimulation and inhibition using fast ferroelectric spatial light modulators and digital holograms,” SPIE Digital Optical Technologies 126240J, Munich (2023)
R. Habibey, J. Striebel, F. Schmieder, J. Czarske, V. Busskamp, “Long-term morphological and functional dynamics of human stem cell-derived neuronal networks on high-density micro-electrode arrays,” Frontiers in Neuroscience 16 (2022) doi:10.3389/fnins.2022.951964
S. Junge, F. Schmieder, P. Sasse, J. Czarske, M.L. Torres-Mapa, A. Heisterkamp, “Holographic optogenetic stimulation with calcium imaging as an all-optical tool for cardiac electrophysiology,” Journal of Biophotonics 15, e202100352 (2022) . doi:10.3389/fnins.2022.951964
Schmieder, F., Habibey, R., Striebel, J., Büttner, L., Czarske, J., & Busskamp, V. “Tracking connectivity maps in human stem cell–derived neuronal networks by holographic optogenetics,” Life Science Alliance 5, (2022). doi:10.26508/lsa.202101268
Schmieder, F., Büttner, L., Hanitzsch, T., Busskamp, V., & Czarske, J. W. "Two-Wavelength Computational Holography for Aberration-Corrected Simultaneous Optogenetic Stimulation and Inhibition of In Vitro Biological Samples," Appl. Sci. 12, 2283 (2022). doi: 10.3390/app12052283