Photonics Dictionary

That radiation characterized by wavelengths ranging from 0.2 to 0.3 µm in the electromagnetic spectrum.

Radiation whose spectrum runs between 100 and 300 nm. Any work with these wavelengths requires evacuated equipment.

Glass designed to absorb most infrared and ultraviolet radiation while transmitting most of the visible region.

Glass that transmits near-ultraviolet radiation but is opaque in the visible region. Also known as woods glass.

A discharge lamp filled with deuterium to produce high-intensity ultraviolet radiation for use in spectroscopic analysis.

An arc lamp whose carbon electrodes are enclosed in a transparent chamber, resulting in an arc that is steadier, lasts longer and emits more ultraviolet radiation.

The photographic recording of a subject that exhibits luminescence only for an extremely short time (10-8 s) after the exciting source is removed. In the process, the subject may be illuminated by...

The optical form of the crystal fluorspar, calcium fluoride, that is utilized for its low optical dispersion, its low refractive index, and its transparency to infrared and ultraviolet radiation.

A device that detects and measures the quantity of exposure to nuclear radiation. It uses a special glass rod that fluoresces when placed under ultraviolet radiation after its exposure to nuclear...

The light flash that occurs when an electrical field is applied to a phosphor already excited by ultraviolet radiation.

The ionization and spark emission due to exposure to ultraviolet radiation.

The hydrogen-derived, ultraviolet radiation running from 1216 to 512 A, discovered by Theodore Lyman in 1914.

The process by which an atomic system changes from one energy level to another by either the emission or absorption of visible, infrared or ultraviolet radiation.

A chemical substance that exhibits fluorescence when excited by ultraviolet radiation, x-rays or an electron beam. The amount of visible light is proportional to the amount of excitation energy. If...

The term photochemical pertains to chemical processes or reactions that are initiated or influenced by the absorption of light. Photochemical reactions involve the interaction of light, often in the...

A photographic method used to obtain an image of a subject by means of its reflectance of incident ultraviolet radiation. An ultraviolet source is used to irradiate the subject, while the reflected...

1. The reduction in the developable density of a photographic emulsion that has been extremely overexposed. 2. In a laser system, damage resulting from ultraviolet radiation that degrades the lasing...

Ultraviolet-C (UV-C) refers to a specific range of ultraviolet radiation with shorter wavelengths than those of visible light. UV-C radiation spans the electromagnetic spectrum with wavelengths...

A type of lamp that emits a high quantity of ultraviolet radiation. This may be an arc lamp encased in a bulb of a glass that is transparent to ultraviolet rays.

A lens intended for use with wavelengths shorter than about 380 nm. It must be made of quartz, calcium fluoride, lithium fluoride or some other material transparent to ultraviolet radiation, as glass...

A microscope used either to detect selective absorption of various wavelengths by the specimen or to achieve increased resolution by virtue of the short wavelength of ultraviolet radiation. Electron...

A technique for measuring the energy spectrum of electrons emitted during the absorption of ultraviolet radiation. This spectrum reveals the characteristic ionization energies of the molecules and...

The photographic recording that uses ultraviolet radiation to irradiate the microscope sample being examined and to form an image of the object on a photographic medium. The components of the...

Ultraviolet reflectance refers to the ability of a material or surface to reflect UV light. Ultraviolet light is electromagnetic radiation with wavelengths shorter than those of visible light,...

A type of glass contrived by Schott that is highly transparent to ultraviolet radiation.

A device that serves to detect the presence of vacuum ultraviolet radiation. It may be photographic film, a thermopile, ion chamber, vacuum photodiode, photomultiplier or channel electron multiplier.

The phenomenon in which alkali metals are transparent to ultraviolet radiation.

A printing process of electrostatic electrophotography that uses a photoconductive insulating medium, in conjunction with infrared, visible or ultraviolet radiation, to produce latent...