Welcome to 3photon.org, an online repository of information about biological fluorescence microscopy with 3-photon excitation.

We aim to provide content of value to a wide range of scientists, from those looking to improve their understanding of the relatively new field of 3-photon microscopy, through experimentalists looking to convert a 2-photon microscope, to grizzled veterans looking for information on the latest developments.

Please contact us with suggested improvements and subscribe to be notified when the site is updated.

Information on 3photon.org is grouped into several categories, accessed via the menu bar.​

  • Fundamentals: Key information about 3-photon excitation, including its performance and limits.

  • Hardware: Practical information on building, aligning and using a 3-photon microscope, including key hardware used in published studies.

  • Resources: Online resources, including data sets and tools available for download, information on imaging conferences and workshops, and links to the many references cited throughout 3photon.org.

  • Site: 3photon.org is under constant development. If there's information you'd like to see on our site - changes you'd like to suggest, perhaps, or new topics you'd like to read about - please contact us. We welcome feedback and suggestions.


3-photon excitation supports imaging to 1.4 mm below the surface of mouse cortex with GCaMP6. Takasaki et al. (2020)