Photonics Dictionary

An enclosure for a calorimeter that allows measurement of unusually low quantities of power and energy.

A measurement of the hardness of a material as determined by the penetration depth of a diamond stylus under a specified amount of pressure.

Label-free refers to a technique or method that does not require the use of additional labels, tags, or markers to detect or identify specific components or entities. In various scientific and...

An experimental research technique by which absorbed or unabsorbed radiation is analyzed in order to characterize and determine material properties, concentration as well as behavior under the...

A device used for measuring the height of clouds from a position on the ground. Measurement technique uses a vertically directed beam stably positioned such that scattered radiation may be detected...

The laser damage threshold refers to the maximum level of laser intensity that a material can withstand without experiencing damage. It is a critical parameter in laser applications and is...

Device which determines particle velocity through the measurement of scattered interference of a beam pair from a single source. The measured light is Doppler shifted which provides information...

Mod Method of obtaining precise temporal mode characteristics.

A laser rangefinder is a device that uses laser technology to measure the distance between the device and a target. It operates on the principle of measuring the time it takes for a laser beam to...

Sparkling granular pattern that is observed when an object diffusely reflects coincident laser light. Speckle appears as an irregularity in many holographs but has been exploited as a measurement...

An instrument usually consisting of a very long interferometer, 3 to 800 m, and a laser light source for the study and measurement of strain, such as those formed by earth tides and gravitational...

A lateral shearing interferometer is an optical device used in interferometry to measure phase differences between two beams of light. Interferometry is a technique that combines and analyzes...

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...

Lens testing equipment refers to a range of specialized tools and instruments used to evaluate the optical performance, quality, and characteristics of lenses. These instruments are essential for...

Lidar, short for light detection and ranging, is a remote sensing technology that uses laser light to measure distances and generate precise, three-dimensional information about the shape and...

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,...

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

A lumen is a unit of measurement used to quantify the amount of luminous flux, which is the perceived power of light. In other words, the lumen measures the total amount of visible light emitted by a...

A Mach-Zehnder interferometer is an optical device used to measure the phase difference between two collimated beams of light. It is named after the physicists Ludwig Mach and Ludwig Zehnder, who...

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 machine vision system is an integrated combination of hardware and software components designed to capture, process, and analyze images to perform automated inspection, measurement, and quality...

An electron system using the effect of a constant magnetic field on electron paths to differentiate electrons that have varying velocities for the accurate measurement of the energies and intensities...

Nondestructive measurement of the delta and alpha of clad optical fibers that involves interferometry with the fiber immersed in an index-matching oil and illuminated perpendicular to the fiber axis.

A gauge designed to measure high degrees of vacuum. It consists of a glass bulb attached to the vacuum vessel, the measurement being made by filling the bulb with mercury and observing the volume of...

A wedge in a rangefinder or heightfinder used to displace the image produced by one telescope so that it coincides with that produced by the other telescope, thus affording a measurement of the...

A MEMS fiber optic switch is a microelectromechanical system (MEMS) device designed to selectively route optical signals between multiple fiber optic channels. These switches utilize miniature...

Metabolic imaging refers to the visualization and quantification of metabolic processes within living organisms, tissues, or cells using various imaging techniques. It provides insights into the...

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.

1. The SI unit of length equal to 10-6 m. Also called micron. 2. A screw thread device used to make accurate physical linear measurements.

The measurement of the intensity of spectral lines by the examination of a very small area under a microscope and the measurement of the density at any point of the image.

A unit of metric measurement, equal to 0.001 m. 25.4 mm equal 1 inch.

The observation and measurement of the flatness of a mirror surface by contacting an optical flat with the mirror. The process generally is done before coating so as not to damage the delicate coated...

In optics, "mode beating" refers to an interference phenomenon that can occur in laser systems with multiple longitudinal modes. Longitudinal modes are specific electromagnetic field patterns that...

For a single-mode fiber, the measurement of the irradiance distribution at the fiber's end face.

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...

In optics, a motion controller refers to a device or system that precisely controls the movement of optical components, such as mirrors, lenses, stages, or other elements within an optical setup. The...

Multi-axis alignment refers to the process of aligning or adjusting components or systems in multiple spatial dimensions or axes. In various technical and engineering contexts, achieving precise...

A spectrometric instrument that detects radiation simultaneously in multiple channels, sorts it spectrally from the deep ultraviolet to the infrared, digitizes the information and stores it for...

A specific form of phase shifting interferometry - commonly referred to as multiple wavelength phase shifting interferometry - this form of interferometry utilizes two short wavelengths to synthesize...

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...

A form of shearing interferometer that contains a simple wedged (plane-parallel) glass plate with a nonzero optical path difference to create interference between split optical wavefronts. The...

A measurement technique used to determine the spatial distribution profile of an electrical or optical quantity of interest which is provided by multiple scans within the near-field region of a...

An instrument devised by Nichols and Hull for use in the measurement of radiation pressure. The device has two small silvered, glass mirrors that are suspended, in the way of a torsion balance, by a...

Unit of measurement of brightness (luminance) equal to one candela per square meter.