three-photon excitation (3PE)

Three-photon excitation refers to the excitation of a system by three photons arriving simultaneously and via virtual energy levels, commonly used in multiphoton microscopy. The three-photon excitation wavelength tends to be roughly triple the usual one-photon excitation wavelength.

See also: multiphoton excitation, one-photon excitation, two-photon excitation, multiphoton microscopy

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Multiphoton Microscopy

Mode-locked pulsed lasers are used for deep tissue imaging and optical sectioning.