Photonics Dictionary

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...

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 angular spectrum approach is a mathematical and computational technique used in the field of optics to analyze and simulate the propagation of optical waves, particularly in the context of wave...

An optical system having one or more lens or mirror components that have nonspherical surfaces. These surfaces, whether reflecting or refracting, serve to advance or retard the incident wavefront,...

A computer-generated hologram (CGH) is a holographic image produced using computational methods and algorithms, rather than traditional optical techniques. CGHs are generated entirely in digital form...

Optical elements that use diffraction to control wavefronts. Diffractive optical elements include diffraction gratings, surface-relief diffractive lenses, holographic optical elements and...

An electro-optic modulator (EOM) is a device used to modulate the amplitude, phase, or polarization of light waves using an external electrical signal. Electro-optic modulation is a fundamental...

The holographic recording of a microscopic specimen whereby magnification is achieved by alteration in a wavelength or radius of curvature between recording and reconstruction of the wavefront. With...

Holography is a technique used to capture and reconstruct three-dimensional images using the principles of interference and diffraction of light. Unlike conventional photography, which records only...

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...

Metasurfaces are two-dimensional arrays of subwavelength-scale artificial structures, often referred to as meta-atoms or meta-elements, arranged in a specific pattern to manipulate the propagation of...

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...

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...

A lens used in the optical testing of an aspheric surface. It converts a spherical wavefront into one that precisely matches the surface under test. When the wavefront is reflected from that surface,...

Optical design software refers to specialized computer programs used by optical engineers, physicists, and designers to simulate, model, analyze, and optimize the performance of optical systems and...

Optical manufacturing tools and machinery encompass a wide range of equipment, instruments, and systems used in the fabrication, shaping, finishing, and testing of optical components and systems....

The relative path difference (or phase shift) traveled between two rays that pass through different mediums from the same object point. For a perfect optical system, the optical path, or distance,...

Optical phase distortion refers to a phenomenon where the phase of an optical wavefront is altered as it propagates through a medium. This distortion can result from variations in the refractive...

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...

The degree to which the surface of a lens causes an incident ray of light to bend, or the amount of convergence or divergence that the surface contributes to a wavefront passing through it.

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...

A phase screen, in the context of optics and wave optics, refers to a surface or medium that introduces a phase delay to an incident wavefront passing through it. This concept is often used in the...

A geometric representation of a light path through an optical device; a line normal to the wavefront indicating the direction of radiant energy flow.

The Shack-Hartmann wavefront sensor is an optical device used for measuring the wavefront aberrations of an optical system. It is widely used in adaptive optics systems to correct distortions and...

Spatial light interference microscopy (SLIM) is an optical microscopy technique that belongs to the category of quantitative phase imaging methods. It is designed to provide high-resolution,...

A vortex phase plate is an optical device designed to impart a phase singularity, commonly referred to as a vortex or phase vortex, onto a light beam. This singularity results in a phase profile...

In an interference pattern, that point where there is no difference between the optical paths of the interfacing wavefronts.