Photonics Dictionary

A tube containing mercury vapor and lined with a phosphor. When current is passed through the vapor the strong ultraviolet emission excites the phosphor, which emits visible light. The ultraviolet...

A type of optical microscope that allows the specimen being viewed to be irradiated by ultraviolet, violet and occasionally blue radiation, causing the specimen to fluoresce.

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 fluorescent screen refers to a phosphorescent or fluorescent-coated surface that emits visible light when exposed to other forms of electromagnetic radiation, such as x-rays or ultraviolet light....

Agents used for testing light sources and natural daylight with visual and instrumental assessment using a set of white metameric pairs.

Autofluorescence refers to the natural emission of fluorescence exhibited by certain biological structures or molecules when exposed to light. Unlike fluorescence that results from the application of...

A blue diode laser is a type of semiconductor laser that emits light in the blue wavelength range of the electromagnetic spectrum, typically between 400 and 500 nanometers. Diode lasers are compact,...

A calcium indicator is a molecule that is sensitive to changes in calcium ion (Ca2+) concentrations in biological systems. These indicators are commonly used in various fields, including cell...

A vacuum tube with an electron gun at one end and a fluorescent screen at the other. Electrons emitted from a heated filament are accelerated by a series of annular anodes at progressively higher...

The application of a cine camera in recording the images on a fluorescent screen. When x-rays are used to produce the screen images, this process is referred to as cine-radiography.

The photographic filming of the action of x-ray images recorded on a fluorescent screen by means of large lens apertures and highly sensitive filters.

A fluorographic method whereby the sensitive photographic medium is pressed against a fluorescent screen to form a visible image.

An incandescent or fluorescent lamp whose emittance spectrum resembles that of daylight.

A cathode-ray tube that increases the brightness or size of an image or forms a visible image from invisible radiation. The focal plane for the optical image is a large, light-sensitive, cold...

The photographic recording of images produced by the electrons from an electron microscope. The electron beam carries the images through an array of three lenses, and an enlarged electron image is...

An instrument that serves to produce an enlarged electron image on a fluorescent screen by focusing an infrared image of a distant object upon a photosensitive cathode.

The face of a cathode-ray tube (CRT) that has a fiber optic sheet attached to its surface. The sheet's fibers are at right angles to the face, allowing the transmittance of the fluorescent trace...

An optical recording technique that uses light source(s), a beamsplitting cube, light detector(s) and an optical fiber chronically implanted in animal brain to deliver excitation light to neurons...

An extremely powerful microscope that renders individual ionized atoms visible by using an electric field to propel the ions to a fluorescent screen where they are magnified.

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...

A powerful method, referred to as FCS, for determining the average diffusion coefficients of fluorescent molecules in solution or membranes. FCS measurements rely on recording the transition of...

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...

A camera with a very high aperture lens or mirror system for photographing x-ray fluorescent screen images, mainly to save the cost of large pieces of 11 x 14-in. film. The film may be 4 x 5-in. cut...

A lens having an extremely high aperture and used in the recording of x-ray fluorescent screen images. It often is specially designed for the camera, the color of the light and the image...

The photographic recording of a visible image formed by the impact of invisible radiation on a fluorescent screen.

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...

1. In a cathode-ray tube, the glow surrounding a bright spot that appears on the fluorescent screen as the result of the screen's light being reflected by the front and rear surfaces of the tube's...

A halogen lamp, also known as a tungsten halogen, quartz-halogen, or quartz iodine lamp, is an incandescent lamp that uses a tungsten filament surrounded by a small amount of halogen gas, such as...

Also known as HCS, an analytical method designed to collect statistically relevant amounts of quantitative data on many parallel cell populations or processes within cells through the combination of...

A desklike apparatus with an opal glass surface illuminated from beneath by fluorescent tubes. It is equipped with roll holders for aerial films and a low-power microscope or some form of...

An electron tube that employs electromagnetic radiation to produce a visual replica of an image produced on its cathode. Electrons ejected from the cathode by the incident radiation are accelerated...

A camera system in which the image formed on the fluorescent screen of an image converter tube in the system is recorded by photography or direct contact printing from the face of the tube.

Photographic recording that uses infrared radiation as the light source to form an image of a microscopic object and a system of lenses and objectives that are transparent to the radiation. The image...

Intravital microscopy is an imaging technique used to visualize biological processes within living organisms, typically in real-time. Unlike traditional microscopy, which involves the examination of...

A cathode-ray tube that serves as a picture tube in a television receiver. The signal representing the picture intensity is transmitted to the electron gun grid so that the beam intensity varies with...

Label-free refers to a technique or method that does not require the use of additional labels, tags, or markers to detect or identify specific components or entities. In various scientific and...

Metabolic imaging refers to the visualization and quantification of metabolic processes within living organisms, tissues, or cells using various imaging techniques. It provides insights into the...

A sensing or image-forming detector that serves to convert infrared rays into visible signals for communication purposes. Also, a form of telescope that generates visible images on a fluorescent...

A fluoroscope equipped with a magnified, fine-grained fluorescent screen to determine the fluorescence emitted by a microscopic source.

Microscopy is a scientific technique that involves the use of microscopes to observe and study objects that are too small to be seen with the naked eye. Microscopes are instruments that magnify and...

The light emitted from tissues without the use of fluorescent dyes as markers. Because cancerous tissues and normal tissues have differing emission spectra, the native fluorescence can be used to...

A nitrogen vacancy (NV) refers to a specific type of defect or impurity in a crystal lattice where a nitrogen atom replaces a carbon atom adjacent to a vacancy (an empty lattice site) in the diamond...

The fluorographic method whereby the visible image (as opposed to the x-ray image) is photographed by mounting a camera in front of the fluorescent screen.