Multiphoton laser scanning microscopy

Although FCS has now been invoked in about 3,000 scientific publications, now at 400 per year, its use before about 1990 was limited by severe technological barriers involving instability of laser light sources, poor sensitivity of photon detectors, noisy electronics, and insufficient computer capacities for the correlation computations. These problems inhibited application of FCS, until suddenly about 1990 the electro-optical and computational technologies advanced so that it became feasible. These advances occurred in synchrony with our creation of Multiphoton Laser Scanning Microscopy, which has enabled effective research on the molecular dynamics of life in living tissues and animals [14]. 

Brown EB, Campbell RB, Tsuzuki Y, Xu L, Carmeliet P, Fukumura D, Jain RK (2001) In vivo measurement of gene expression, angiogenesis and physiological function in tumors using multiphoton laser scanning microscopy. Nat Med 7 864-868... 

J. Paoli, M. Smedh, A.M. Wennberg, M.B. Ericson, Multiphoton laser scanning microscopy on non-melanoma skin cancer morphologic features for future non-invasive diagnostics. J. Invest. Dermatol. 128, 1248-1255 (2008)... 

A very different concept of multi-beam scanning is realized in Multifocal Multiphoton laser scanning Microscopy (TriM Scope, La Vision BioTec). In this... 

Multiphoton or two-photon laser scanning microscopy is an alternative to confocal and time-resolved microscopy for bioimaging applications. The principle has been discussed in Lanthanides Luminescence Applications and concerns a two-photon excitation from the simultaneous absorption of two photons in a single quantized event. A bioprobe that normally absorbs ultraviolet light (Xex = 350 nm) can also be excited by two photons of NIR light, at 700 nm (the wavelength is twice that required for one-photon excitation). These two photons must interact simultaneously, which means in a very small lapse time. The instrumentation requires pulse lasers to provide sufficient power, as the photon density must... 

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