Photonics Dictionary

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

The partial differential equations for the spatial and time dependence of electric and magnetic fields inside a semiconductor. They are the analog of Maxwell's equations, which apply to the electric...

Instrumentation designed to permit the perception, recording or measurement of scenes under conditions of low incident illumination.

Luminous flux emitted by a source in a given range of directions; the unit of measure is the lumen/steradian, now known as the candela.

A dielectric sphere with an index of refraction that varies with distance from the sphere center. A parallel beam of rays is focused on the lens surface at a point diametrically opposite the...

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....

A camera lens, used in macrophotography, that is designed and corrected to produce optimum definition of a nearby object when it is photographed at a magnification of approximately1:1.

An arranged series of coils, magnets or electromagnets disposed in such a way that the resulting magnetic fields generate a Lorentz force that is used to then focus or deflect beams of rapidly moving...

A wedge-shaped piece of quartz typically found in a polarimeter to monitor and rotate the plane of polarization of plane polarized light. A Martens wedge can also be used in combination with other...

A transmission line having no wave reflection along its path.

The greatest luminous transmittance possible for a specified chromaticity.

The mathematical set of equations showing the relationship between oscillating electric and magnetic fields that are generated by an oscillating electric charge. Intrinsic to Maxwell's equations is...

The average intensity of a light source measured over all directions.

The average luminous intensity of a point light source measured over all directions.

A meniscus lens is an optical lens that has one side that is concave (curved inward) and the other side that is convex (curved outward). It can be categorized into two types based on its optical...

The process or act of measuring the geometric properties of an object or image.

A metalens, short for "metasurface lens," is a type of optical lens that uses nanostructured materials to manipulate light at a subwavelength scale. Unlike traditional lenses made of glass or other...

A type of fiber optic sensor that detects changes in pressure, vibration, sound level or acceleration by monitoring the ejection of light from the fiber core to the cladding caused by microbending...

The fundamental tool of microdensitometry, the microdensitometer is an instrument used for the precise measurement of microscopic optical densities (i.e. optical absorption) by detection of faint...

The science that deals with the measurement of optical absorbance (i.e. optical densities) over microscopic areas of a given specimen or optical material.

A microlens array is a grid-like structure composed of numerous small lenses, typically arranged in a regular pattern. Each individual lens in the array is referred to as a microlens. These...

An image-forming system having curved mirrors in place of transparent glass components. Mirror lenses are commonly used for astronomical purposes as well as cheap solutions for very long focal length...

The simultaneous occurrence of direct and diffuse transmission.

The modulated transfer function (MTF) is a measure used in optical engineering and imaging science to describe the ability of an optical system to transfer the contrast of an object to an image. It...

A method used to detect internal or residual microstresses in a material by using a laser beam to locate changes in polarization caused by the stress.

MTF analysis/measurement equipment refers to instruments and tools used to measure and analyze the modulation transfer function (MTF) of optical systems. The MTF is a quantitative measure of the...

Also called sine wave response and contrast transfer function. The modulation transfer function is the ratio of the modulation in the image to the modulation in the object as a function of frequency...

A molded lens is an optical lens manufactured using a molding process, typically involving the shaping of a material, such as glass or plastic, into the desired lens shape. This process involves...

In physics, momentum transfer is the amount of momentum transferred from one particle to another during particle collision or interaction. This phenomenon can be utilized in various areas of physics...

An array of refractive microlenses that are round, square and hexagonal and as small as 15 µm. They are used for Hartmann testing, laser diode collimation and other applications that require...

Capacity of a vision system to capture an image of an object in motion and to resolve the direction and speed of that motion.

A lens with internally adjustable elements to produce a range of focal lengths. Unlike a true zoom lens, a multifocal lens must be refocused each time the focal length is changed. See variable-focus...

A multihaul transceiver is an optical transceiver module designed to support multiple network architectures or transmission technologies within a single compact device. It offers versatility and...

A computer architecture used in parallel processing whereby all the processing elements are operating under their own local control rather than under the direction of a central control unit.

A block that can hold more than one lens or blank.

A camera that uses a rotating mirror to project sequential images onto lenses that are arranged in an arc. The reflected images can then be recorded on stationary film. By using an 8-mm frame format,...

A collection of color samples arranged in charts according to equal visually spaced steps in Munsell hue, value and chroma.

Numerical scale of chroma devised by A.H. Munsell and exhibited in the Munsell Book of Color.

Founded by professor Albert Munsell. In the field of colorimetry, the Munsell color system is a color space that identifies a given color based on three different color measurements. These...

Numerical scale of hue devised by A.H. Munsell and exhibited in the Munsell Book of Color.

Alphanumerical description of color according to Munsell hue, value and chroma.

Numerical scale of lightness devised by A.H. Munsell and exhibited in the Munsell Book of Color.

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 neuromorphic vision sensor is a type of imaging device designed to mimic the structure and functioning of the human visual system. Inspired by the biological principles of the human eye and brain,...

A coating applied to a neutral density glass that is designed to reduce the amount of light evenly across the transmitted light spectrum with no color distortion. These coatings are designed to...