* FRET Fluorescence resonance energy transfer is used to study protein interactions, detect specific nucleic acid sequences and used as biosensors, while fluorescence lifetime ( FLIM ) can give an additional layer of information.

FRET has also been used in tandem with Fluorescence Lifetime Imaging Microscopy ( FLIM ) or fluorescently conjugated antibodies and flow cytometry to provide a detailed, specific, quantitative results with excellent temporal and spatial resolution.

16 ~ 64 multichannel PMT systems have been commercially available, whereas the recently demonstrated CMOS single-photon avalanche diode ( SPAD )- TCSPC FLIM systems can offer additional low-cost options.

Thus, FRET measurements using FLIM can provide a method to discriminate between the states / environments of the fluorophore.

The lifetime of the fluorophore signal, rather than its intensity, is used to create the image in FLIM.

FLIM has primarily been used in biology as a method to detect photosensitizers in cells and tumors as well as FRET in instances where ratiometric imaging is difficult.

In neurons, FLIM imaging using pulsed illumination has been used to study Ras, CaMKII, Rac, and Ran family proteins.

FLIM has been used in clinical multiphoton tomography to detect intradermal cancer cells as well as pharmaceutical and cosmetical compounds.

FLIM imaging is particularly useful in neurons, where light scattering by brain tissue is problematic for ratiometric imaging.

Fluorescence-lifetime imaging microscopy or FLIM is an imaging technique for producing an image based on the differences in the exponential decay rate of the fluorescence from a fluorescent sample.

* Fluorescence Excited-State Lifetime Imaging

* Fluorescence lifetime ( Spontaneous Emission Lifetime ) as a function of Nd ions concentration

* Intraoperative Fluorescence Imaging

This includes the Optical Microscope, Transmission Electron Microscope, Scanning Electron Microscope, Fluorescence Microscope, and by Confocal Microscopy.

* WITec SNOM System-NSOM / SNOM and Hybrid Microscopy techniques in combination with AFM, RAMAN, Confocal, Dark-field, DIC & Fluorescence Microscopy techniques.

* Immunostaining of cells on slides by Microscopy ( ImmunoHistoChemistry or Fluorescence ), on microplates by photometry including the ELISPOT ( and its variant FluoroSpot ) to enumerate B-Cells or antigen-specific cells, in solution by Flow cytometry

*" Fluorescence Microscopy " lecture by Nico Stuurman ( UCSF )

* Two-photon Fluorescence Light Microscopy, ENCYCLOPEDIA OF LIFE SCIENCES

Fluorescence anisotropy can defined quantitatively as

Fluorescence in several wavelengths can be detected by an array detector, to detect compounds from HPLC flow.

Fluorescence two-dimensional differential gel electrophoresis ( 2-D DIGE ) can be used to quantify variation in the 2-D DIGE process and establish statistically valid thresholds for assigning quantitative changes between samples .< ref > Tonge, R., Shaw, J., Middleton, B., Rowlinson, R., Rayner, S., Young, J., Pognan, F., Hawkins, E., Currie, I. and Davison, M. ( 2001 ), Validation and development of fluorescence two-dimensional differential gel electrophoresis proteomics technology.

Fluorescence can be an indication of crude oil staining, or of the presence of fluorescent minerals.

Fluorescence can also be used to redirect photons, see fluorescent solar collector.

Other optical techniques are also used: Fluorescence Correlation and Cross-Correlation Spectroscopy ( FCS / FCCS ) can be used to gain information of fluorophore mobility in the membrane, Fluorescence Resonance Energy Transfer ( FRET ) can detect when fluorophores are in close proximity and optical tweezer techniques can give information on membrane viscosity.

Fluorescence lifetimes can be determined in the time domain by using a pulsed source.

Fluorescence microscopy can be used to find out where the fluorescent probe is bound to the chromosomes.

Fluorescence is considered to be one of the best methods for quantification, but is less sensitive than chemiluminescence.

* Fluorescence, not Rayleigh Scattering, causes the sky to be blue.

Fluorescence in the life sciences is used generally as a non-destructive way of tracking or analysis of biological molecules by means of the fluorescent emission at a specific frequency where there is no background from the excitation light, as relatively few cellular components are naturally fluorescent ( called intrinsic or autofluorescence ).

Fluorescence microscopy and confocal microscopy are used to detect fluorescent signals with good intracellular detail.

Fluorescence spectrocopy is used in, among others, biochemical, medical, and chemical research fields for analyzing organic compounds.

Atomic Fluorescence Spectroscopy ( AFS ) techniques are useful in other kinds of analysis / measurement of a compound present in air or water, or other media, such as CVAFS which is used for heavy metals detection, such as mercury.

* Fluorescence in situ hybridization ( FISH ), a technique used in genetics to detect DNA sequences

Fluorescence tags are used to give visual readout on a protein.

Fluorescence of certain rocks and other substances had been observed for hundreds of years before its nature was understood.

Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.

Fluorescence occurs when an orbital electron of a molecule, atom or nanostructure relaxes to its ground state by emitting a photon of light after being excited to a higher quantum state by some type of energy:

Fluorescence quantum yields are measured by comparison to a standard.

Fluorescence in minerals is caused by a wide range of activators.

Top: Both X-chromosome territories are detected by Fluorescence in situ hybridization | FISH.

Top: Both X-chromosome territories are detected by Fluorescence in situ hybridization | FISH.

Fluorescence is generally measured at a 90 ° angle from the excitation source to minimize collection of scattered light from the excitation source, often such a rotation is provided by a Pellin-Broca prism on a turntable which will also separate the light into its spectrum for closer analysis.

In the past the assay was conducted by using the touchstone method but currently ( most often ) it is done using X-ray Fluorescence ( XRF ).

Fluorescence is schematically illustrated with the classical Jablonski diagram, first proposed by Jablonski in 1933 to describe absorption and emission of light.

Like classical T Tauri stars, many brown dwarfs are surrounded by disks of gas and dust which accrete onto the brown dwarf .< ref name = uv > First Ultraviolet Spectrum of a Brown Dwarf: Evidence for H < sub > 2 </ sub > Fluorescence and Accretion, John E. Gizis, Harry L. Shipman, and James A. Harvin, Astrophysical Journal 630, # 1 ( September 2005 ), pp. L89 – L91.

Fluorescence microscopy with fluorescent reporter proteins has enabled analysis of live cells by fluorescence microscopy, however cells are susceptible to phototoxicity, particularly with short wavelength light.

Fluorescence microscopy is central to many techniques which aim to reach past this limit by specialised optical configurations.

Top: Both X-chromosomes are detected, by Fluorescence in situ hybridization | FISH.

* 1919 Robert John Strutt, A Study of the Line Spectrum of Sodium as Excited by Fluorescence.

Fluorescence of a molecule is quenched by specific analytes, e. g., ruthenium complexes are quenched by oxygen.