Photonics Dictionary: F

A plate consisting of fused optical fibers with both surfaces ground and polished, and having the entrance surface curved to match the image curvature of the input lens system. The plate transmits to...

A fiber optic gyroscope (FOG) is a type of gyroscope that uses the interference of light waves to detect changes in orientation or rotation. It operates based on the principle of the Sagnac effect,...

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 bundle of optical fibers arranged randomly for the purpose of transmitting energy, not an image.

A fiber optic preform is a cylindrical glass rod or tube used as the starting material for manufacturing optical fibers. It serves as the precursor from which optical fibers are drawn. The process of...

A flexible single- or multifiber cable having a bundle of glass fibers arranged to transmit an image.

A device used for coding messages and having a fiber bundle that is aligned at both ends and scrambled in the middle, potted and cut. The resulting halves of the bundles serve as encoders or decoders...

A fiber optic sensor is a device that uses optical fibers to detect and measure physical, chemical, biological, or environmental parameters. Unlike traditional electrical sensors, fiber optic sensors...

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...

A fiber optic transceiver, often simply referred to as an "optical transceiver," is a device used in fiber optic communications to transmit and receive data over optical fibers. It integrates both a...

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...

The use of thin flexible glass or plastic fibers as wave guides — or "light pipes" — to channel light from one location to another. Fiber optics is based off of the principle of total...

A microscope in which laser light is delivered through single-mode fibers that replace the pinhole usually used in confocal microscopy. When the Gaussian mode is imaged from the fiber output onto the...

A fiber-coupled LED (light-emitting diode) refers to an LED device that is optically coupled to an optical fiber for the purpose of efficient light transmission. In this configuration, the LED serves...

A fiber-coupled photoconductive antenna (FCPA) is a type of optoelectronic device that combines a photoconductive antenna with optical fibers for the purpose of generating or detecting terahertz...

A method of terminating optical fibers by forming a lens directly on the end of the fiber, eliminating the need for precise end-to-end placement or epoxy sealing in fiber connections.

An optical instrument consisting of an objective lens, a coherent (usually flexible) fiber bundle and an eyepiece to examine the output of the fiber bundle.

1. In raster scan television, one of the two scans that are interlaced to make up a frame. 2. See field of view.

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.

1. A lens situated at or near the plane of an internal image to project the aperture of a previous objective or erector upon the aperture of a following lens. 2. A lens at or near the plane of a...

The field of view (FOV) refers to the extent of the observable world or the visible area that can be seen at any given moment through a device, such as an optical instrument, camera, or sensor. It is...

Intensity of emission as a function of direction in a given plane.

An aperture located at an image plane of an optical system that determines the size and shape of the image.

A measuring eyepiece with a screw-micrometer-driven crosshair used to measure the size of the image.

The process by which the light from the images of photographic film is encoded into electrical signals for video transmission.

An interferometer spectrometer designed to measure thicknesses of thin films or layers by recording the interferogram and by having a computer within the instrument to establish the distance between...

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...

For a Fabry-Perot interferometer or etalon, a value for the transmission bandwidth which can be calculated as the ratio of the free spectral range to the full width half maximum of the transmission...

The spectral transmission window in silica-based fibers between 830 and 850 nm.

Fixed-pattern noise is the measure of the static (nontemporal) differences between pixels when the detector is evenly illuminated. In microbolometers, this effect is mostly caused by mismatch between...

Fizeau fringes are interference fringes observed in an interferometer, specifically in a Fizeau interferometer. The Fizeau interferometer is named after the French physicist Armand Fizeau, who...

A device used to measure the speed of light by adjusting the rotation of a toothed wheel so that light passing through one tooth opening is reflected through the next. This device has since been...

The use of high temperatures, between 2000 and 3000 °C, to excite emission lines from a sample in spectroscopic analysis.

Any of a number of instruments that uses a flame to vaporize a solution of the chemical being analyzed so that light may be passed through the vapor. Monochromation of the transmitted light is...

A part of the spectrochemical analysis of a sample that deals with the excitation of that sample by flame analysis.

The procedure applied to flame-excited line emissions to determine spectra and wavelengths.

The study of the reflection or transmission properties of specimens as a function of wavelength after they have been excited by flame-analysis techniques.

The study of flames by means of a laser emitting blue light and a spectrometer to measure the green fluorescence created by the flame chemistry.

The emission spectrum formed by the radiation from a sample that has been evaporated by a nonluminous flame.

Nonimage-forming light, concentrated or diffuse, that is transmitted through the lens to the image. It is frequently the result of reflections from lens surfaces, a lens barrel, shutter or lens mount.

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.

The study and interpretation of the spectra of substances after they have absorbed the radiant energy emitted by a brief, intense light source.