Photonics Dictionary

The necessary increase of a photograph's exposure time as the result of the additional absorption of light by the filter being used.

A technique used in radiography to obtain an unblurred image of a moving object by the use of very short x-ray exposures, such as one microsecond, to record the image.

A sensitometer that utilizes an electronic flashtube or a photoflash lamp as both the light source and the shutter for obtaining short-duration exposures.

Fluence is a term used in various scientific and technical disciplines to describe the amount of something per unit area. The specific meaning of fluence can vary depending on the context in which it...

The combination of the organic dye in a stained specimen and the antibodies produced that is detected by exposure to light.

Germicidal ultraviolet (GUV) refers to a specific range of UV radiation that has disinfectant properties capable of killing or inactivating microorganisms, including bacteria, viruses, and fungi. The...

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 decrease in effect in developable density on a photographic plate formed by a second exposure to radiation having a longer wavelength, usually red or infrared.

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

High dynamic range (HDR) refers to a technology that allows for a broader and more dynamic range of luminosity in visual content, such as images or videos. It is particularly associated with displays...

A high-speed motion camera, also known as a high-speed camera or slow-motion camera, is a specialized imaging device designed to capture fast-moving events or phenomena at extremely high frame rates....

A method of producing x-ray exposures as short as 0.03 µs; the primary application is in ballistic radiography.

A plotted relation between Log E (logarithm to base 10 of exposure in metercandle seconds) and density (logarithm to base 10 of opacity).

Hyperchromic shift refers to an increase in the absorption of light, leading to a higher absorbance, often observed in certain chemical or biological substances upon undergoing a structural change....

With respect to photography, the process used to increase the effective speed of an emulsion between manufacture and exposure.

An image intensifier, also known as an image intensification tube or image intensification device, is a specialized electronic device used to amplify low-light-level images to make them visible to...

A measure of the closeness with which an optical image is capable of resembling the original object. The factors that affect image quality are lens aberrations, diffraction, dirt and stray light...

A modified form of an image-retaining panel that can be used in subdued daylight. This is achieved by adding a layer of zinc oxide between the panel's phosphor layer and its rear electrode. The zinc...

An exposure meter designed to measure the light striking an object and used at a suitable location in a scene.

A shutter in which the opening and closing times for a large aperture setting occupy a substantial fraction of the total exposure time so that apertures and time pair readings from an exposure meter...

A photoconductor that demonstrates increased conductivity during its exposure to infrared radiation.

Also known as integrated exposure. A measurement of light from sources that vary rapidly with time, defined as the integral of instantaneous power and time and expressed as units per second.

Integration time, in the context of optics, imaging systems, and sensor technology, refers to the duration over which a sensor collects and accumulates incoming light or signal. It is a crucial...

An intensified charge-coupled device (ICCD) camera is an advanced imaging device that combines the capabilities of both an image intensifier and a charge-coupled device (CCD) sensor to achieve...

A closed vessel with electrodes of different potentials that is used to determine how much ionization took place in a gas after its exposure to x-rays or radioactive emissions.

The laser damage threshold refers to the maximum level of laser intensity that a material can withstand without experiencing damage. It is a critical parameter in laser applications and is...

Extended period exposure photographs of a laser light created with various patterns within full image (laser graffiti).

A short term for latent image intensification, a process much like hypersensitizing in photography, but used after exposure and before development of the negative.

The pattern of physical or chemical changes that has taken place in a photographic emulsion, by its exposure to light, that will form a visible image when the emulsion is developed. Also known as...

A type of additive color photography using a lenticular structure impressed on a film base and a camera lens with a filter having three sectors of red, blue and green. Exposure of the film through...

Any device that is used to sense and measure light. See exposure meter; photoelectric exposure meter; photoelectric photometer; reflected light meter.

The maximum circular area over which radiance and radiant exposure can be averaged.

A line-scan camera, also known as a line-scan image sensor or linear array camera, is a type of digital camera designed to capture images one line or row of pixels at a time, rather than a full...

A linear image sensor is a type of solid-state electronic device used to capture and convert light into electrical signals. Unlike area image sensors (such as CCD or CMOS sensors), which capture an...

Lithography is a key process used in microfabrication and semiconductor manufacturing to create intricate patterns on the surface of substrates, typically silicon wafers. It involves the transfer of...

A type of photometer calibrated in luminance units (candles per square unit, or lamberts). In photography an exposure meter contains a luminance meter to record the average luminance of a scene.

Luminescence is the emission of light that occurs without the involved substance undergoing a significant increase in temperature. In other words, it is the production and emission of light by a...

SI unit of light exposure.

A type of high-speed photographic shutter that uses Faraday rotation to produce exposure times as fast as 1 microsecond. It consists of two polarizers, set with their planes of polarization at right...

In the context of thin film deposition processes such as evaporation or sputtering, masks are used to selectively deposit material onto substrates, creating patterns or structures with precise...

A camera used to reduce originals onto film for easy storage. There are two basic types: one in which the film is fixed during exposure, and one in which the film is exposed while moving past an...

A computer-generated, phase-and-amplitude, off-axis hologram made by a multi-exposure technique that uses three computer generated transmission masks. Each mask controls one fixed-phase component of...

A camera equipped with a lens and a long length of perforated film, the latter being moved intermittently between exposures by a pulldown claw or sprocket. A rotating shutter serves to cut off the...

A camera that uses a rotating mirror to project sequential images onto lenses that are arranged in an arc. The reflected images can then be recorded on stationary film. By using an 8-mm frame format,...

A lithography method that allows the transfer of fine-pitch gratings from a phase mask into photoresist. The exposure takes place with the light coming under an oblique angle to the mask. The...