Two-photon Microscopy
Multi-photon fluorescence microscopy is a relatively novel imaging technique in cell biology. It relies on the quasi-simultaneous absorption of two or more photons (of either the same or different energy) by a molecule. During the absorption process, an electron of the molecule is transferred to an excited-state molecular orbital. The molecule (i.e. the fluorophore) in the excited state has a high probability (> 10 %) to emit a photon during relaxation to the ground state. Due to radiationless relaxation in vibrational levels, the energy of the emitted photon is lower compared to the sum of the energy of the absorbed photons, that is, the detected light is red-shifted.
Two-photon fluorescence microscopy is the most common multi-photon fluorescence application in cell biology, and can be a superior alternative to confocal microscopy due to its deeper tissue penetration, efficient light detection.
Please visit the website of our strategic partner, Thorlabs Inc, to learn more about the Nonlinear Imaging Techniques using our femtosecond laser systems:
Advanced Imaging>>Laser Scanning Microscopy>>Confocal Camera (for the relevant information, please got to the tab "Nonlinear Imaging")