Photonics Dictionary

Optical coherence tomography (OCT) is a non-invasive imaging technique used in medical and scientific fields to capture high-resolution, cross-sectional images of biological tissues. It provides...

A rigid medium, generally a polycarbonate substrate coated with a reflective aluminum layer, that stores information (such as audio, video or data) as digital bits in the form of variations in the...

A periodic structure formed by intersecting or superimposed laser beams. These beams can trap atoms in low-potential regions, forming a pattern of atoms resembling the structure of a crystal.

Optical materials refer to substances or compounds specifically chosen for their optical properties and used in the fabrication of optical components and systems. These materials are characterized by...

An optical modulator is a device used to control or modify a property of light, such as its amplitude, phase, polarization, or frequency. Optical modulators are essential components in a wide range...

Optical parametric amplification (OPA) is a process in nonlinear optics where a weak signal beam is amplified by a much stronger pump beam through the nonlinear interaction in a nonlinear optical...

The process whereby the number of atoms or atomic systems in a set of energy levels is changed by the absorption of light that falls on the material. This process raises the atoms to specific higher...

An optical testing instrument is a device or system used to evaluate and measure the performance, quality, and characteristics of optical components, systems, and devices. These instruments play a...

Optical tweezers refer to a scientific instrument that uses the pressure of laser light to trap and manipulate microscopic objects, such as particles or biological cells, in three dimensions. This...

The partially reflective mirror at the end of the laser cavity that is the source of the beam. It controls the coupling percentage for high output power and maintains correct mode structure in the...

The condition of the numerical aperture or beam diameter of the laser, LED, or other optical source being larger than the optical fiber core or other driven source. Also called overfilled launch...

A device using a parametric amplifier inside a resonant optical cavity to generate a frequency-tunable coherent beam of light from an intense laser beam of fixed frequency. This device is tuned by...

The use of a reflective device, which can be fashioned from a variety of materials including gases, solids, dyes, aerosols, semiconductor crystals and plasmas, to replicate a laser beam by reversing...

Phase matching is a crucial concept in the field of optics, particularly in nonlinear optics and the generation of coherent light. It refers to the condition where the phases of two or more waves,...

A method of producing disks for erasable optical data storage. Information is recorded by a laser beam that generates pits on the surface of the disk while it is being cryogenically cooled. Erasure...

An optical medical instrument that uses an intense, precisely focused beam of light to stop weakened blood vessels from hemorrhaging. The thermal effect of the beam strengthens the weakened vessels...

Spectroscopy used to study the concentration, diffusion and Brownian motion of small particles suspended in a fluid by measuring dynamic fluctuations of light that is scattered or fluoresced by the...

The induction of an electric field in a semiconductor by an incident laser beam. The technique has rapid response time at room temperature.

The photographic recording of data, in binary form, for storage in memory. Exposure is achieved by a cathode-ray tube or by modulating a continuous-wave laser beam with a Kerr cell, both relative to...

A plasma accelerator is a type of particle accelerator that uses electric fields and magnetic fields to accelerate charged particles, typically electrons or ions, by exploiting the motion of charged...

Introduced into the laser beam from localized fluctuations in current density within the plasma itself. These fluctuations represent macroscopic changes of gain in the laser.

A mixture of ionized gas and metal vapor generated by impingement of the laser beam onto a material being welded or a weld joint. The plume causes absorption and/or scattering of the incident laser...

A polygonal mirror, also known as a multifaceted mirror or facet mirror, is a type of optical component used in various laser systems, optical scanners, and imaging devices. It consists of a flat or...

In laser welding or heat treating, the instantaneous laser beam power per unit area. This parameter is key in determining the fusion zone profile (area of base metal melted) on a workpiece.

An accurately produced hole of any size and shape that is used as a masking device in an optical system. Pinhole apertures of accurate diameters often are produced by laser beam penetration or by...

The compression and intensification of a laser pulse of a specific width into a smaller pulse width. A spherical cavity, in conjunction with a beam compressor, is efficient for pulse amplification....

A pump laser is a type of laser used to provide the necessary energy to the gain medium of another laser or laser system, initiating the process of stimulated emission and producing laser light. The...

1. An optical distance finder that depends on triangulation of two convergent beams on an object from disparate view points. 2. A device that depends on the measurement of time of wave travel from an...

An image that appears when a hologram is illuminated by a suitable light source, generally a laser beam.

A device employed to identify toxic agents lingering on the ground or in the air from up to three miles away, by using laser beams to detect infrared light-absorption patterns that can be analyzed to...

A robotic process commonly employed by automakers that enables high-speed and flexible production throughput by using swiveling optics for precise beam positioning.

A ring laser gyroscope (RLG) is a type of gyroscope that uses laser light to detect and measure changes in orientation. It operates based on the Sagnac effect, which is a fundamental principle of...

A Risley prism, also known as a Risley prism pair or Risley rotating prism, is an optical device used for controlling the direction of a laser beam or other optical beam by independently rotating two...

A structured light device using a rapidly rotating laser to project a beam of light that appears to the human eye as a continuous circle; used as a reference marker on walls or landscape for...

Also called scanning laser acoustic microscope. A device that uses high-frequency ultrasound waves to penetrate surfaces. A scanning laser beam is used as a detector, which transmits information...

1. The variation in intensity of a light beam as it travels through the atmosphere. 2. In radiation physics, a light flash formed by an ionizing event in a phosphor; a flash formed when rapidly...

A self-interference effect that generates random patterns; secondary speckle pattern (SSP) typically occurs in diffuse reflections of a laser on paper, white paint or rough surfaces. By tracking both...

Selective laser melting (SLM) is an additive manufacturing (AM) or 3D printing technology that belongs to the powder bed fusion category. SLM is primarily used for metal additive manufacturing, where...

Self-phase modulation (SPM) is a nonlinear optical phenomenon that occurs when an intense laser beam passes through a medium, causing a change in the phase of the light due to its interaction with...

A singlet lens is an optical lens made from a single piece of material, typically glass or plastic, with one or both surfaces being spherical or aspherical. It is the most basic type of lens used in...

Sisyphus cooling is a technique used in atomic physics to achieve ultracold temperatures of atoms or molecules by exploiting the periodic motion of particles in optical traps or lattices. The name...

A gelatinous fluid that can be used as a porous thin-film coating for optical components, including laser beam collimators, or as a protective coating for glass and crystalline materials.

A solid-state laser is a type of laser that uses a solid gain medium (as opposed to a liquid or gas) to produce coherent light. The term "solid-state" refers to the fact that the active medium, where...

The diagnostic procedure that uses ultrasonic energy to probe the body and, with the help of laser beams, a reflecting membrane to produce a three-dimensional picture.