Photonics Dictionary

In a laser, the fraction of plasma volume used by a particular transverse mode of oscillation, a determinant of the gain available to the mode.

Mode hopping in the context of lasers refers to a phenomenon where a laser system abruptly switches from one longitudinal mode to another. In a laser, different longitudinal modes represent distinct...

Mode locking is a technique used in optics and laser physics to generate short pulses of light with extremely high peak powers. In mode locking, the phases of different longitudinal modes (specific...

The pulse-to-pulse fluctuations in power distribution among modes of a Fabry-Perot laser, which can result in system-limiting noise.

A multimode laser characteristic defined as the ratio of power loss for the second mode to that of the lowest mode.

A form of laser output noise that is caused by thermal, mechanical, or acoustical disturbances of the cavity length. Mode sweeping occurs when the length of the laser cavity changes as a result of...

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.

A zone plate produced by a computer and having a binary structure that can be etched into a chromium or quartz layer. It often is used in laser machining, in which the machining of small holes with...

The highest frequency at which a laser diode can be driven and still be modulated acceptably that further results in the maximum rate of change (modulation) in output frequency that can be obtained...

In a laser diode, the photocurrent produced by a photodiode that detects the emission from the rear facet of the semiconductor chip. It can be used to provide feedback control of the forward current...

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...

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...

Method for reducing laser speckle in which the object field comes from a real diffuse object or the reconstructed object field from a hologram. During recording of the image, an aperture is moved in...

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...

Describing a laser that emits simultaneously at more than one wavelength.

A monolithic laser diode incorporating multiple coupled emitters.

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 function that quantifies the performance degradation of coherent communications systems, imaging systems and all systems that rely on the spot size of a laser beam that has propagated along an...

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...

Nanopositioning refers to the precise and controlled movement or manipulation of objects or components at the nanometer scale. This technology enables the positioning of objects with extremely high...

A unique glass made up of nano-structured materials to create millimeter sized monolithic glass space-variant polarization converters which ultimately alter the way light propagates through and is...

A nanotube, also known as a nanotubule or simply a tube-like structure, is a nanoscale cylindrical structure composed of various materials, including carbon, boron nitride, or other compounds....

In a laser diode, lateral motion of the beam center at the facet when the drive current is changed.

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.

Literally, neodymium:yttrium-aluminum-garnet. A cylindrical rod of yttrium-aluminum-garnet doped with neodymium that is the active medium of the Nd:YAG laser, a highly serviceable solid-state device...

A strip or annulus of glass coated with a semitransparent material such as inconel. The coating thickness, and as a result its transmission, varies linearly as a function of distance. The neutral...

A pollution-measuring device used to detect the presence of nitric oxide regardless of other gases present. It utilizes the principle of laser magnetic resonance (LMR).

Zone of laser operation in which the direct, reflected or scattered light exceeds the laser's MPE and (by ANSI standards) requires the use of protective eyewear.

A nonlinear crystal is a type of crystal that exhibits nonlinear optical properties when subjected to intense electromagnetic fields, typically from laser light. Unlike linear optical materials,...

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.

A class of optical phenomena that can be viewed only with nearly monochromatic, directional beams of light, such as those produced by a laser. Harmonic generation and the stimulated Raman effect are...

Nonlinear optical materials are substances that exhibit optical properties that are not linearly proportional to the intensity of incident light. In other words, these materials produce optical...

The coupling of laser or light beams via nonlinear optical techniques such as four-wave mixing to achieve spatial variation of the electrical field of the target beam. This technique is also referred...

Nonlinear optics is a branch of optics that studies the optical phenomena that occur when intense light interacts with a material and induces nonlinear responses. In contrast to linear optics, where...

Nonlinear polarization refers to the phenomenon where the polarization of a material responds nonlinearly to an applied electric field. In linear systems, the polarization of a material is directly...

Off-axis paraboloid and ellipsoid mirrors are specialized optical components used in various optical systems, particularly in applications requiring precise focusing, collimation, or imaging of...

On-board optics refers to optical systems integrated into devices or platforms for various purposes, such as imaging, navigation, communication, and sensing. These systems are crucial in a wide range...

An optical accumulator is a concept or device that collects and stores optical energy or data for subsequent use. This can be applied in various fields within optics and photonics: Optical data...

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,...

An instrument used to test lenses by utilizing the optical transfer function. It consists of a HeNe laser, a beamsplitter and two mirrors.

An optical barcode reader, commonly known as a barcode scanner, is a device that uses optical technology to capture and interpret data encoded in barcode symbols. Barcodes are typically printed on...

A term referring to an optical force field used to trap and stabilize particles acted upon by a force such as laser light.

Optical cements and adhesives are specialized materials used in the assembly and bonding of optical components in optical systems. These materials are designed to provide secure and durable bonds...