Photonics Dictionary

Technology that corrects the shape of reflective optics; primarily applied in large telescope systems, in order to compensate for slowly varying changes in temperature, wind and mechanical stress.

A type of fiber optic sensor that detects alteration in position, distance, pressure, liquid level or temperature by transmitting light across a gap to a reflector; a change in the light returned to...

A thermometric instrument used for the detection and measurement of radiant energy. Its essential component is a short narrow strip covered with a dead black absorbing coating and mounted at the...

Crystal growth method that resembles static freeze, but that induces growth by removing the ampoule from the furnace so that the freezing-point temperature gradient is unchanged during the growth...

Calorimetry is a branch of science that involves the measurement of heat flow in physical or chemical processes. It encompasses various techniques and instruments used to quantify heat transfer,...

Carbonization is a process in which organic materials are heated in the absence of air, leading to the decomposition of the material and the production of carbon-rich residue. During carbonization,...

A numerical representation of the rate at which a material will exhibit dimensional changes as a direct result of changes in temperature.

A fiber Bragg grating (FBG) is a type of optical filter that is inscribed or "written" into the core of an optical fiber. It consists of a periodic modulation of the refractive index along the length...

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...

Small clefts or fissures that penetrate the glass surface in the form of short-hooked crescents. Fire cracks result from a sudden excessive change in temperature.

Fluorescence lifetime imaging (FLIM) is an advanced imaging technique that provides information about the lifetime of fluorescence emissions from fluorophores within a sample. Unlike traditional...

Fused quartz and silica are closely related materials, both composed primarily of silicon dioxide (SiO2), but they are produced through different manufacturing processes and have distinct properties...

High-modulus elastic fibers that exhibit the following differences from conventional elastic fibers: Increasing temperature decreases recovery force (the fibers are enthalpic vs. conventionally...

An infrared detector is a device that is used to detect and measure infrared radiation, which lies beyond the visible spectrum of light. These detectors are utilized in various applications,...

Used to detect radiation from the infrared region. The functional process includes absorption of infrared radiation, which causes a temperature change, consequently altering the physical properties...

Heat measurement method in which the sample is made part of the interferometer and the temperature increase is determined by measuring the change in optical pathlength through the material. By moving...

The internet of things (IoT) refers to a network of interconnected physical devices, vehicles, appliances, and other objects embedded with sensors, actuators, software, and network connectivity....

Laser drift typically refers to a phenomenon where the frequency or wavelength of a laser source gradually changes over time. In the context of lasers, stability in terms of frequency or wavelength...

Liquid crystals are a state of matter that exhibits properties intermediate between those of conventional liquids and solid crystals. In a liquid crystal, the molecules are ordered like those in a...

A magnon is a quasiparticle representing a quantized spin wave in a magnetic material. In other words, it is a collective excitation of the spins of electrons in a magnetic solid, analogous to the...

The temperature at which the solid phase of a material is in equilibrium with the liquid phase, or when the material changes from a solid to a liquid.

A microbubble resonator is a device used in photonics and optical physics for the precise manipulation of light waves. It consists of a micro-sized, gas-filled spherical cavity (the "microbubble")...

Equipment that supports microscopic live-cell imaging by managing the gas, media perfusion, temperature and other factors to which a sample is exposed. While reducing the negative impacts these...

An approximated measure of the smallest change in color temperature detectable by the human eye, defined as the reciprocal of the color temperature times 106. Also called mired or reciprocal...

In a thermal imaging system, the smallest change in blackbody equivalent temperature that can be detected clearly by the system as a function of target frequency.

The distortion of an object's true image as the result of abnormal atmospheric disturbances along the path traveled by the light. The atmospheric disturbances common with mirages are a result of a...

Mode hopping in the context of lasers refers to a phenomenon where a laser system abruptly switches from one longitudinal mode to another. In a laser, different longitudinal modes represent distinct...

A form of laser output noise that is caused by thermal, mechanical, or acoustical disturbances of the cavity length. Mode sweeping occurs when the length of the laser cavity changes as a result of...

In a thermal imaging system, the change in temperature that yields a signal-to-noise ratio of unity.

Optical cements and adhesives are specialized materials used in the assembly and bonding of optical components in optical systems. These materials are designed to provide secure and durable bonds...

Optical glass refers to a type of glass specifically engineered and manufactured for use in optical components and systems, such as lenses, prisms, mirrors, and filters. Optical glass is...

Optical phase distortion refers to a phenomenon where the phase of an optical wavefront is altered as it propagates through a medium. This distortion can result from variations in the refractive...

An erasable data recording and storage medium that uses a laser to heat the crystalline surface of the disc to a certain temperature, at which it becomes amorphous and records a bit of information;...

A phase-modulated sensor is a type of sensor that uses modulation of the phase of a signal to measure changes in a physical quantity. In such sensors, variations in the phase of the signal are...

Photolithography is a key process in the manufacturing of semiconductor devices, integrated circuits, and microelectromechanical systems (MEMS). It is a photomechanical process used to transfer...

Piezoelectric motion systems are mechanical systems that utilize piezoelectric materials to generate controlled motion or displacement. Piezoelectric materials exhibit the piezoelectric effect, which...

Motion of a fiber into and out of the ferrule. This effect is often caused by changes in temperature.

Unlike the thermocouple or bolometer, the pyroelectric infrared detector is a current source with an output proportional to the rate of change of its temperature. Capable of extremely rapid response...

Recombinase polymerase amplification (RPA) is a molecular biology technique used to rapidly amplify specific DNA or RNA sequences under isothermal conditions, meaning it does not require the...

Remote sensing is a method of data collection and observation where information about objects, areas, or phenomena on Earth's surface is gathered from a distance, typically using sensors onboard...

Spectral repeatability refers to the consistency and reproducibility of spectral measurements across multiple trials or instances. It is a measure of how well a measurement instrument or system can...

A light source that does not fluctuate despite temperature changes.

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

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,...

A solid-state semiconducting structure (basically one of the bolometers) that changes electrical resistance with temperature. Materially, some kind of ceramic composition is used. A thermistor has...