Photonics Dictionary

A thin-film device containing miniature optical components connected via optical waveguides on a transparent dielectric substrate, whose lenses, detectors, filters, couplers and so forth perform...

A filter that controls the spectral composition of transmitted energy partially by the effects of interference. Frequently, these filters are made up of thin layers of metals and dielectrics,...

Interferometric modulator display (IMOD) is a type of display technology used in electronic devices, known for its energy efficiency and ability to produce high-quality reflective color displays....

A filter that transmits infrared and ultraviolet but is opaque to visible radiation.

A computer-generated kinoform used for data processing because of its use of incoherent light and its wide field of view, which facilitates parallel processing of two-dimensional data.

Usually consists of a set of filters that attenuate specific wavelengths but transmit as much visible radiation as possible.

A narrow linewidth optically transmissive or reflective component intended for use with a highly monochromatic or single mode source.

Laser optics refers to a broad category of optical components and systems designed for manipulating and controlling laser light. Laser optics play a crucial role in shaping the characteristics of...

A Laurent polarimeter is an instrument used in optics for measuring the rotation of plane-polarized light caused by optically active substances. Optical rotation, also known as optical activity, is a...

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...

A homogeneous optical medium or coating that transmits only in particular regions of the spectrum. It is used to change or modify the total or relative energy distribution of a beam of light.

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...

Liquid crystal on silicon (LCoS) is a display technology that combines liquid crystal materials with silicon-based semiconductor technology to create high-resolution, high-quality images. LCoS...

A solution or combination of solutions that serves as a filter.

An immersion liquid used to treat polarizing filters to eliminate the effects of surface variations and to minimize the optical path difference between that part of the spectrum that passes through...

A lock-in amplifier is a specialized electronic instrument used to extract and measure small signals embedded in noise or interference. It is particularly useful in fields such as spectroscopy,...

A long-pass filter is an optical filter that allows longer wavelengths of light to pass through while blocking or attenuating shorter wavelengths. These filters are designed to transmit light with a...

A filter that is transparent to longer wavelengths but opaque to shorter wavelengths.

In digital image processing, a method of convolution that reduces random noise by replacing the value of each pixel with the average of that pixel plus its neighbors, or of the neighbors alone. Also...

A type of filter consisting of a series of birefringent crystals and polarizers invented by French astronomer Bernard Lyot for isolating and observing significant wavelengths of solar light.

A machine vision lens is a specialized optical lens designed for use in machine vision systems, which are used for automated inspection, measurement, and quality control in industrial applications....

Machine vision, also known as computer vision or computer sight, refers to the technology that enables machines, typically computers, to interpret and understand visual information from the world,...

A filter that maximizes signal-to-noise ratio so that a waveform of known shape can be separated from random noise.

In image processing, a method of local smoothing by replacing each pixel with the median gray level of neighboring pixels.

A thin layer of metal deposited on the surface of a substrate. The film may serve as a reflector, beamsplitter, neutral density filter or electromagnetic interference filter.

An interference filter in which a very thin metal foil with a periodic array of square holes (inductive mesh) or a thin plastic substrate with an array of metal squares (capacitative mesh) is used as...

Metasurfaces are two-dimensional arrays of subwavelength-scale artificial structures, often referred to as meta-atoms or meta-elements, arranged in a specific pattern to manipulate the propagation of...

A micro-ring resonator is a compact optical device that utilizes the resonant behavior of light within a small ring-shaped waveguide structure to selectively enhance or filter certain wavelengths of...

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...

Minimum object distance, often abbreviated as MOD, refers to the closest distance at which a camera lens or optical system is capable of producing a sharp and focused image. In photography, this term...

A device used in measuring the attenuation of multimode optical fibers. A short reference length of fiber when combined with the mode filter has approximately the same angular output distribution of...

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 filter that transmits a single spectral line emitted by a line source.

A monochromator is an optical instrument used to isolate and select a narrow range of wavelengths from a broader spectrum of light. The term monochromator is derived from "monochromatic," meaning...

A group of four cameras loaded with different combinations of filters and film (one is usually an infrared color film) to permit the recording of the same subject in four separate regions of the...

Multispectral imaging is a technique that involves capturing and analyzing images at multiple discrete spectral bands within the electromagnetic spectrum. Unlike hyperspectral imaging, which acquires...

The use of narrow bandpass filters and special photographic emulsions to discern features of a surface that would not be easily recognizable with regular black-and-white or color photographic methods.

Nanophotonics is a branch of science and technology that explores the behavior of light on the nanometer scale, typically at dimensions smaller than the wavelength of light. It involves the study and...

An optical pyrometer that is equipped with a narrow bandpass filter to transmit a limited number of wavelengths to the sensing device.

A near-infrared (NIR) camera is an imaging device designed to capture images in the near-infrared region of the electromagnetic spectrum. The near-infrared spectrum typically extends from about 700...

Glass containing small quantities of neodymium oxide that is used as a filter plate in color television or as a lasing medium (Nd:glass) in solid-state lasers.

A light filter that equally decreases the intensity of all wavelengths of light without altering the relative spectral distribution of the energy.

Derivative of the half-tone screen process involving the fabrication of a binary pulse-width modulated copy of the continuous-level input using a halftone screen and spatial-filtering single...