Photonics Dictionary: A

Discipline within optical physics that addresses sound vibration, phonon effects and their influencing behavior within optical elements and systems.

Technology that corrects the shape of reflective optics; primarily applied in large telescope systems, in order to compensate for slowly varying changes in temperature, wind and mechanical stress.

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...

The analysis of the properties of radiation, such as light, when acted upon by variations in the atmosphere. Blue and red skies, along with ice halos, glories, coronas and rainbows can all be...

The area of optics in which the wave nature of a particle is exploited to carry out very accurate interferometry and other optical techniques with atoms instead of photons. In this process, particles...

Ray oriented and assumed to propagate orthogonal to the optical axis

A dispersion relation defined in order to value the reciprocal amount of dispersion. It is defined as the refractivity over the difference in index values of the shortest and longest visible...

A form of roof prism used to invert an image. The prism has faces cut normal to the optical axis; therefore, the prism may be placed within the optical path of a system and invert the image without...

A reflecting prism that inverts the image. The image is reflected four times internally and emitted laterally. The prism is cut normal to the optical axis while the image is internally reflected from...

A departure from ideal paraxial imaging behavior. The distortion of an optical field wavefront as it is propagated through the elements of an optical system. The field distortion is due to the...

Designed for the function of optical wavefront analysis. Shack-Hartmann camera aberration sensors use a lens array to image the wavefront to the CCD image plane. Live feedback may be applied through...

The alteration and reduction of color with the addition of white light. The perceived color shift that occurs as the monochromatic-white combination meets the eye and is interpreted by the brain. The...

Optical surface damage due to abrasive rubbing. Abrasion damage affects are less than the thickness of the optical coating layers. Surface investigation may be achieved by aluminization of the coated...

Powder used to produce a smooth optical surface through abrasive polishing. Compounds may produce a surface finish specified for each.

An instrument that uses optical filtration in order to measure the transmittance for a discrete range or specific number of wavelengths.

The value of the distance of distinct vision, minimum focusing distance or near point, divided by the focal length of the lens. Magnification is produced when the optic is placed at its focal...

The natural log of the ratio of absorbed intensity over the total intensity which gives a constant value assuming a stable volume as well as energy. In optical physics the absorbance may be defined...

An optical lens manufactured to control the transmission of light over a specified wavelength range. Low absorption lenses are produced which are anti-reflection coated for UV, VIS and IR wavelengths...

The range of angle or solid angle values by which light may enter an optical system.

A curve expressing an optical fiber's total transmitted power as a function of its launch angle at the input.

A broadband continuum resonator that confines a wide range of wavelengths. From the optical confinement a single wavelength may be released by means of a tuning grating.

Optic surface cleaning liquid that may be applied to glass, crystal, dielectric and metal surfaces; however, may not be applied to plastic and polymer materials.

An achromat, in the context of optics, refers to a type of lens or lens system designed to reduce chromatic aberration. Chromatic aberration is an optical phenomenon where different colors of light...

The optical reconstruction of image information contained in a sound field. First the diffraction pattern, formed by an object irradiated by ultrasonic rays, interferes with a mutually coherent...

The angular change of an incident beam due to vibrational induced refractive index changes within a crystal.

A system designed with a laser as a light source and a means for producing sound waves extending beyond 100 MHz to deflect light efficiently.

Light diffracted by a solid (usually quartz in crystal or fused form) traversed by acoustic waves. If the ultrasonic wavelength is larger than the diameter of the light beam, the diffraction orders...

The altering of lightwaves by acoustic waves in a solid medium.

A device that varies the amplitude and phase of a light beam; e.g., from a laser or by sound waves. Also known as a Bragg cell.

An acousto-optic modulator (AOM) is a device that utilizes the interaction between sound waves and light waves to modulate or control the intensity, frequency, phase, or direction of laser beams. It...

A bulk crystalline optic which permits the propagation of light through a volume of index altered material. The variation in refractive index along the material volume is due to a piezoelectric...

The change in refractive index that occurs as acoustic vibrations are transmitted through an optical material.The index changes are periodic in relation to the frequency, spatial orientation, and...

A thermoplastic or optically transmitting hard plastic produced by applying polymerization initiator and heat to a monomer.

That point in the electromagnetic spectrum at which an optical system focuses the most chemically effective rays.

That layer in a semiconductor injection laser or light-emitting diode that provides optical gain.

The layer of material in a laser diode from which the optical radiation is emitted; light producing region

In biaxial crystals, the principal angle that bisects the smaller angle between the optic axes.

1. In optics, the housing, usually cylindrical, that contains the lenses and iris diaphragm of a camera. 2. In fiber optics, a device for coupling two connectors.

The process of adjusting input pixel by pixel at the filter plane to adapt to nondeal phase behavior in an optical correlator.

The intermolecular attraction between two surfaces, as between a substrate and a coating; it is an important factor in the durability of optical thin films.

An intermolecular substance that serves to hold materials together. Two types are used in the optical industry: one, which must be transparent and colorless, to cement lenses together; and a...

An optical illusion in which distant objects are lighter in tone and less distinct in outline than those closer to the observer because of the atmospheric diffusion of light.

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

An optical system with object and image points at infinity. Literally, "without a focal length."

A support device in which a column or chamber of air permits the free travel of a mobile part. In optical mounting and positioning equipment, air bearings are of two types, linear or rotary,...

The central peak (including everything interior to the first zero or dark ring) of the focal diffraction pattern of a uniformly irradiated, aberration-free circular optical element or system.

An optical tooling instrument consisting of an objective lens, a focusing lens, an optical micrometer, a reticle and an eyepiece. The alignment telescope projects a precise line of sight to which a...

Left- and right-hand circularly polarized beams that are produced at different velocities by passing plane-polarized light through an optical substance. When recombined, they exhibit different phases...