Photonics Dictionary

A near-infrared (NIR) spectrometer is an analytical instrument used to measure the absorption, transmission, or reflection of light in the near-infrared region of the electromagnetic spectrum....

Near-infrared spectroscopy (NIRS) is a non-invasive analytical technique that uses the near-infrared region of the electromagnetic spectrum to study the absorption of light by molecules in a sample....

A Nernst glower, also known simply as a Nernst lamp or Nernst filament, is a type of incandescent lamp or radiant heater based on the Nernst effect. It was invented by the German physicist and...

A type of radiation detector designed to recognize nonlinear optical effects, such as the Raman effect, by means of a directional, nearly monochromatic light beam; e.g., a laser beam.

An optical assembly refers to a collection of optical components that are carefully arranged and aligned to perform a specific function within an optical system. These components may include lenses,...

Optical coherence tomography (OCT) is an imaging technique used in medical diagnostics and biomedical research to obtain high-resolution, cross-sectional images of biological tissues. An OCT imaging...

Optical design software refers to specialized computer programs used by optical engineers, physicists, and designers to simulate, model, analyze, and optimize the performance of optical systems and...

In compact disc and CD-ROM technology, the portion of the drive that projects the laser light onto the surface of the media and picks up the resulting reflections read as data. The head includes the...

A device used to detect and measure small amounts of rotation. The rotating object contains a reflecting surface from which a beam of light is reflected onto a positional detector. A large distance...

Optical materials refer to substances or compounds specifically chosen for their optical properties and used in the fabrication of optical components and systems. These materials are characterized by...

Optical noise refers to undesirable fluctuations or disturbances in an optical signal that can affect the quality or integrity of the transmitted information. This type of noise is particularly...

Optoelectronics is a branch of electronics that focuses on the study and application of devices and systems that use light and its interactions with different materials. The term "optoelectronics" is...

A concave mirror that has the form of a paraboloid of revolution. The paraboloidal mirror may have only a portion of a paraboloidal surface through which the axis does not pass, and is known as an...

A photodetector, also known as a photosensor or photodiode, is a device that detects and converts light into an electrical signal. Photodetectors are widely used in various applications, ranging from...

A photodiode detector is a semiconductor device that converts light into an electrical current. It operates based on the principle of the photoelectric effect, where photons of light incident on the...

An electronic tube instrument in which the anode current varies with the intensity of light incident on the cathode.

A photomultiplier tube (PMT) is a highly sensitive vacuum tube that detects and amplifies low levels of light. It is widely used in various applications where high sensitivity, fast response times,...

Photon-rich typically refers to an environment or situation where there is an abundance of photons present. In the context of optics, photon-rich environments are those where there is a high density...

A photonic engine refers to a device or system that utilizes photonics, or the science and technology of generating, controlling, and detecting photons (particles of light), to perform various...

A photonic integrated circuit (PIC) is a compact and integrated device that incorporates multiple photonic components and functions on a single chip, similar to the way electronic integrated circuits...

Photoplethysmography (PPG) is a non-invasive optical technique used to detect changes in blood volume in tissues. It measures variations in light absorption caused by the pulsatile nature of blood...

A phototransistor is a type of semiconductor device that converts light energy into electrical signals. Similar to a regular transistor, it consists of a semiconductor material (such as silicon) with...

A structure consisting of a thin film of liquid crystal sandwiched between light-polarizing filters that have received a surface lubricant. Depending on motion, the transducer acts as a highly...

A PIN photodiode is a type of photodetector or semiconductor device used to convert light signals into electrical signals. The name "PIN" is derived from the arrangement of the three semiconductor...

Quantum efficiency (QE) is a measure of the effectiveness with which a device or system, typically in the context of photonics or electronics, converts incoming photons (light) into a useful output...

A quantum well is a structure in quantum mechanics that confines particles, such as electrons or holes, in one spatial dimension. This confinement leads to quantized energy levels, creating a...

A means of high resolution study through the application of soft and hard x-rays onto a sample surface in order to obtain image information from 1-10 nm layers and surfaces. The x-ray source emission...

Reflectance spectroscopy is a technique used to analyze the reflective properties of materials across various wavelengths of the electromagnetic spectrum. By measuring the reflectance of light from a...

A ring laser gyroscope (RLG) is a type of gyroscope that uses laser light to detect and measure changes in orientation. It operates based on the Sagnac effect, which is a fundamental principle of...

Scanning electron microscopy (SEM) is an advanced imaging technique used in microscopy to obtain high-resolution, three-dimensional images of the surfaces of solid specimens. SEM achieves this by...

A scintillation crystal, also known simply as a scintillator, is a material that emits light when it interacts with ionizing radiation such as gamma rays, x-rays, or charged particles. The emitted...

A scintillation detector is a radiation detection device that utilizes scintillation crystals to detect and measure ionizing radiation, such as gamma rays, x-rays, or charged particles. It consists...

Short wavelength infrared (SWIR) refers to the portion of the infrared spectrum that encompasses wavelengths roughly between 1,000 and 3,000 nanometers (nm). In the electromagnetic spectrum, infrared...

A silicon photodiode is a semiconductor device that converts light into an electrical current. It is a type of photodetector specifically designed for detecting and measuring light intensity. Silicon...

A single-photon avalanche diode (SPAD) is a specialized type of photodetector designed to detect extremely weak optical signals, down to the level of single photons. SPADs are widely used in...

Spectral flow cytometry is an advanced flow cytometry technique that expands the capabilities of traditional flow cytometry by utilizing spectral information from fluorochromes to enhance...

An optical instrument for forming the spectrum of a light source and recording it on a film. The dispersing medium may be a prism or a diffraction grating. A concave grating requires no other means...

A time-to-amplitude converter (TAC) is an electronic circuit that converts a time interval between two events into an amplitude or voltage signal. TACs are commonly used in various scientific and...

A method of measuring distance by recording a single scene from two points of perspective. Surveying instruments can be used; in autofocus systems, rangefinders and three-dimensional imaging systems,...