Photonics Dictionary

A small telescope mounted on a tripod and free to rotate about a vertical axis. A spirit level is mounted over the telescope and adjusted so that when the bubble is central, the telescope axis is...

The material removed during diamond machining of glass components.

Swept-source optical coherence tomography is an imaging technique used in medical diagnostics, particularly in ophthalmology, to visualize and analyze the internal structures of biological tissues,...

A swept-source laser, also known as a wavelength-swept laser, is a type of laser that rapidly and continuously changes its emission wavelength over time. This continuous wavelength tuning is achieved...

swept-source Raman spectroscopy is an advanced analytical technique that combines the principles of Raman spectroscopy with a swept-source laser system. It enables rapid and sensitive chemical...

A positive after-image that is maintained for a minute or more.

A standard for fiber optic telecommunications interfaces, with a 1300-nm data link operating over single-mode fiber at data rates of 52, 155 and 622 Mb/s.

The technique of generating ultrashort -- down to subpicosecond -- pulses by pumping a dye laser with mode-locked laser pumps with cavity lengths the same as, or a submultiple of, that of the dye...

A mode of transmission whereby the sending and receiving stations operate continuously at a fixed relationship of phase and frequency, generating signals to control the timing of the data that are to...

A synchrotron is a type of particle accelerator that uses magnetic fields to steer charged particles, typically electrons or positrons, in a closed, circular or elliptical path. The name synchrotron...

An imaging technique in which an object moving through an interference field formed in space scatters light and is spatially recorded on a photographic film as a hologram. If the interference field...

A system-on-chip (SoC) is an integrated circuit (IC) that incorporates all necessary components of a computer or electronic system onto a single chip. This typically includes a microprocessor or...

Angular tracking measurement estimated from the properly normalized image second-moment tensor.

1. The term used to describe any of the many instruments used to remotely record physical dimensions, such as strain, temperature or pressure, and transmit this data to a receiving station. 2. A...

The science of sensing and measuring information at some remote location and transmitting the data to a convenient location for reading or recording.

The principles and techniques involved in the use of telephotometers to measure atmospheric extinction.

The use of head-mounted displays and body-operated remote actuators to control distant machinery. Provides a virtual environment for humans to control devices, robots, etc., in a hostile real...

An afocal optical device made up of lenses or mirrors, usually with a magnification greater than unity, that renders distant objects more distinct, by enlarging their images on the retina.

The base used to hold an astronomical telescope. It may be either altazimuth, with horizontal and vertical axes of rotation, or equatorial, with one axis parallel to the Earth's axis of rotation and...

A television receiver that receives the signals generated by a television camera directly, or remotely through a radio signal. It may be used to continuously check image and sound reception; as a...

An electronic device used to encode video and audio signals of a television camera into radio waves that are broadcast to remote receivers. The video and audio components are transmitted...

Teloscopy, while not a commonly used term, could be understood in the context of principles related to telescopes and their applications in observation and measurement. If we interpret teloscopy as...

A coating having pigments that change color when exposed to heat. This effect has been widely used to monitor hot spots in mechanical parts.

A technique used to suppress extreme noise amplification during digital image reconstruction that relies on smoothing and differentiation of the data by simplified least squared procedures.

A terahertz spectrometer is a scientific instrument used to measure and analyze the properties of materials in the terahertz frequency range, typically spanning from about 0.1 to 10 terahertz (THz),...

Terahertz (THz) refers to a unit of frequency in the electromagnetic spectrum, denoting waves with frequencies between 0.1 and 10 terahertz. One terahertz is equivalent to one trillion hertz, or...

A contraction for "texture element." A base unit used in computer graphics that defines the surface of three-dimensional objects. Texels are obtained from texture memory and represent color to be...

Thermal imaging is a technology that detects infrared radiation (heat) emitted by objects and converts it into an image, known as a thermogram, which displays temperature variations in different...

A thermal-infrared camera, often referred to simply as a thermal camera, is a type of imaging device that detects infrared radiation emitted by objects due to their temperature. Unlike traditional...

Thermal interface materials (TIMs) are substances or compounds used to enhance the thermal conductivity between two surfaces in contact. These materials are primarily employed in electronic devices,...

Distortion of an optical component as a result of heat, which can influence the divergence and the mode quality of a beam passing through the component.

The emission of radiant energy in which the energy emitted originates in the thermal motion of the atoms or molecules of the source material.

A source that emits radiant energy when its molecules or atoms are thermally excited.

A material that changes color as it is heated or cooled.

A device composed of dissimilar metals that, when welded together, develop a small voltage dependent upon the relative temperature between the hotter and colder junctions. Banks of thermocouples...

Examination of the processes whereby heat energy is converted into other forms of energy.

An instrument that transforms heat energy into electrical energy.

A refrigeration method based on the Peltier effect. When an electric current passes through a thermocouple of two dissimilar metals joined in two places, heat is absorbed at the cold junction and...

A solar cell that uses a thermoelectric converter, consisting of two sheets of metal with a semiconductor sandwiched between them, to generate electricity.

Also known as analog thermogram. The resultant photograph, illustrating, in tones ranging from black to white, the spatial relationship of the infrared radiation temperatures of the different details...

The instrument used to collect thermal radiation information on an object by scanning. It consists basically of a detector, a photoconductive element that converts incident radiation to an electrical...

Thermography is a technique that involves the use of an infrared imaging device, called a thermal camera or infrared camera, to detect and visualize the infrared radiation emitted by objects. This...