Photonics Dictionary: F

A femtosecond laser is a type of laser that emits ultrashort pulses of light with durations on the order of femtoseconds, where one femtosecond is equal to 10-15 seconds. These lasers are capable of...

A fiber laser is a type of laser in which the active gain medium is an optical fiber doped with rare-earth ions such as erbium, ytterbium, or neodymium. Fiber lasers generate coherent light through...

A fiber optic imaging bundle is a specialized optical device composed of multiple optical fibers bundled together. Each fiber optic strand within the bundle acts as a conduit for transmitting light....

A fiber optic spectrometer is a device used for measuring the spectral content of light. It utilizes optical fibers to transmit light from a source to a spectrometer unit, where the light is...

Filoviruses are a family of viruses that are responsible for severe and often fatal hemorrhagic fevers in humans and non-human primates. The name "filovirus" is derived from their filamentous...

A flexible display refers to a type of electronic visual display that is designed to be bendable, foldable, or rollable, allowing for unconventional form factors and enhanced portability. Unlike...

Flow chemistry, also known as continuous-flow chemistry, is a chemical manufacturing process where reactions take place in a continuous stream of fluids (liquids or gases) rather than in batch...

Flow cytometry is a powerful technique used in biology and medicine for the quantitative analysis of the physical and chemical characteristics of cells and particles suspended in a fluid. The method...

Fluorescence is a type of luminescence, which is the emission of light by a substance that has absorbed light or other electromagnetic radiation. Specifically, fluorescence involves the absorption of...

Fluorescence lifetime imaging (FLIM) is an advanced imaging technique that provides information about the lifetime of fluorescence emissions from fluorophores within a sample. Unlike traditional...

Fluorescence microscopy is a specialized optical imaging technique used in biology, chemistry, and materials science to visualize and study specimens that exhibit fluorescence. Fluorescence is the...

Fluorescent proteins are proteins that exhibit the property of fluorescence, which is the ability to absorb light at a specific wavelength and emit light at a longer wavelength. These proteins are...

A fluorophore is a molecule or a portion of a molecule that has the ability to emit light upon excitation by an external energy source, such as ultraviolet or visible light. The process by which a...

Förster resonance energy transfer (FRET) is a mechanism describing the transfer of energy between two closely spaced fluorescent molecules. This phenomenon is named after the German scientist...

A free-electron laser (FEL) is a type of laser that generates coherent, high-intensity electromagnetic radiation by using a beam of accelerated electrons as the lasing medium. Unlike traditional...

A frequency comb is a precise and regular series of equally spaced spectral lines, or frequencies, that are generated with great accuracy. The term "frequency comb" is often associated with the Nobel...

FTIR (Fourier transform infrared) spectrometer is a powerful analytical instrument used to obtain an infrared spectrum of absorption or emission of a solid, liquid, or gas sample. It operates based...

Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging technique that measures changes in hemoglobin concentration in the brain. It utilizes near-infrared light to penetrate the...

Fusion ignition refers to the point in a controlled nuclear fusion reaction where the energy released by the fusion reactions becomes self-sustaining, leading to a continuous release of energy...