Photonics Dictionary

A salt of formic acid that can be used to enhance the photosensitivity of silver halide crystals.

Transformation of an image, such as a change in position or scale, that does not alter the linearity of the original image.

Any of the constants that relate the tendency of the director to remain parallel to restoring torques throughout the media. The three constants of importance in liquid crystal displays are: splay --...

A mode of laser printing in which each pixel is printed four times, providing sharper lines and a continuous tone from one-quarter the amount of image data, compared with single-raster output.

A wide-field multiobject spectroscopy system used in astronomy, in which a bundle of low-loss optical fibers positioned on the target images is rearranged at its other end into a linear array along...

The processing of an image or portion of an image by transform coding and analysis. Fourier, Hadamand, Kronecker and Eigenvector transforms are applicable to image transformation.

One class of nonlinear space-invariant transformation processes used for processing convolved and multiplied signals.

The code signifying the location of the information being sought on a CD-ROM.

A 2D profile sensor is a type of sensor used in various industrial and technological applications to measure and capture detailed information about the shape, contour, or profile of an object in two...

A 3D profile sensor, also known as a 3D profiling sensor or 3D depth sensor, is a technology that is used to capture and measure the three-dimensional shape or profile of an object or a scene. These...

3D profiling, also known as three-dimensional profiling, refers to the process of capturing, analyzing, and visualizing the three-dimensional shape, geometry, and surface characteristics of objects...

An Abbe refractometer is a scientific instrument used to measure the refractive index of liquids and solids. Named after the German physicist Ernst Abbe, this device operates on the principle of...

An absorption hologram is a type of hologram in which the image is formed by variations in the absorption of light within the recording medium. Unlike traditional holograms that rely primarily on...

An absorption line is a dark line in a spectrum that occurs when a specific wavelength of light is absorbed by atoms or molecules in a medium (such as a gas or a solid) as light passes through it....

An absorption peak refers to a sharp increase or spike in the absorption of electromagnetic radiation at a particular wavelength or energy level. It is a distinctive feature in the absorption...

Absorption spectroscopy is a fundamental analytical technique used to study the interaction between electromagnetic radiation and matter. It involves measuring the absorption of light by a sample...

An absorption spectrum is a graphical representation of the absorption of light by a material as a function of wavelength, frequency, or energy. It displays the specific wavelengths of light that are...

An accelerometer is a sensor or transducer that measures the rate of change of velocity of an object, or in simpler terms, it measures acceleration. Accelerometers are widely used in various...

Accessible radiation refers to the portion of radiation from a source that can be reached or detected by humans, instruments, or devices under specific conditions of use. This term is often used in...

Achirality refers to the property of a molecule or object that is superimposable on its mirror image. In other words, an achiral molecule or object does not exhibit chirality, meaning it does not...

An acoustic surface wave, often abbreviated as ASW, is a type of mechanical wave that travels along the surface of a material, such as a solid or a liquid, rather than propagating through its volume....

An acoustical hologram refers to a three-dimensional representation of sound waves in space, analogous to optical holography but applied to acoustic waves. Unlike visual holography, which creates...

Acoustical holography is a technique used to visualize and analyze sound fields in three-dimensional space. It involves capturing the complex spatial distribution of acoustic waves, much like how...

The acousto-photorefractive effect refers to a phenomenon in which acoustic waves (sound waves) interact with light waves (photons) within a photorefractive material, resulting in changes in the...

Active optics refers to a technology used in telescopes and other optical instruments to improve the quality of images by dynamically adjusting the shape of optical components, such as mirrors, in...

Active transport is a biological process by which cells move molecules or ions across their cell membrane against their concentration gradient, meaning from a region of lower concentration to a...

An active matrix liquid crystal display (AMLCD) is a type of flat-panel display technology that utilizes an array of thin-film transistors (TFTs) to control the individual pixels on the screen. This...

An OLED display that has an integrated electronic backplane as its substrate. Active-matrix OLED displays use at least two thin-film transistors (TFTs) to control the on-current at each OLED cell or...

Visual acuity specifically refers to the clarity or sharpness of vision, typically measured by the ability to discern the details of objects at a specific distance. It is a fundamental measure of the...

An optical adapter typically refers to a device or component used in optical systems to facilitate connections between different types of optical fibers, connectors, or interfaces. Here are a few...

Adaptive deconvolution is a computational method that aims to improve the resolution and fidelity of signals or images that have been degraded by known or unknown factors, such as blur, noise, or...

Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of atmospheric distortions. The Earth's atmosphere can cause light passing through it...

A television format with enhanced vertical resolution (400 lines as compared with the standard 330) that, unlike high-definition television, can operate on existing bandwidths and with existing...

Advanced driver assistance systems (ADAS) refers to a set of safety features and technologies designed to assist drivers in the driving process and enhance overall vehicle safety. These systems use...

The use of optical or electronic recording systems to extract information from the terrain, while aloft, for reconnaissance applications.

Agri-photonics refers to the application of photonics technologies in agriculture. Photonics involves the generation, manipulation, and detection of light and other forms of radiant energy whose...

A category of systems designed to communicate a photo taken from the air (e.g., aircraft, balloon, satellite) to a ground station. It can be done by direct television transmission of the photo, or by...

Alternating current (AC) is an electrical current in which the direction of flow of electric charge periodically reverses. This reversal occurs at regular intervals, typically in a sinusoidal...

Analog adaptive resonance theory (AART) is a neural network model within the broader framework of adaptive resonance theory (ART), which was introduced by Stephen Grossberg. ART is a cognitive and...

Information presented as a continuously variable relationship between a signal and a standard.

Analog-to-analog (AA) refers to the process or system that involves the conversion or transmission of analog signals from one form to another, without converting them into digital signals at any...

Anisotropy refers to the property of exhibiting different values or characteristics when measured in different directions. In various fields, including physics, materials science, and geology,...

A type of solar eclipse that occurs when the sun is at perihelion and the moon is at apogee. Because the apparent size of the moon is insufficient to cover the sun, the outer edge of the solar disc...

Light-absorbing material that is applied to the back support of any bright image under inspection to prevent the formation of a secondary image.

The formation of an image by a pinhole aperture that transmits radiation, such as gamma radiation.