Photonics Dictionary

See honeycomb table; indexing table.

Laser light show effects equipment including optics and mechanical devices that reflect, position or distort the laser beam, but not including the laser itself.

A matrix-controlled display that has information storage at the display surface, and requires that an element be addressed only once to assure that it is on or off.

An optical test table made up of two outer layers or "skins'' bonded to either side of a honeycomblike core, usually of aluminum or steel. It results in equal quality with greatly reduced weight...

A desklike apparatus with an opal glass surface illuminated from beneath by fluorescent tubes. It is equipped with roll holders for aerial films and a low-power microscope or some form of...

Generally, a rotatable table with scales marked in degrees. The fiducial marking also may be a vernier scale. The same scheme is applied to linear movement. Such devices are often applied to...

In image processing, the memory that stores the values for the point processes. Input pixel values are those for the original image, while output values are those displayed on the monitor as altered...

An excited energy state of an atom or atomic system that has a longer lifetime than the ordinary excited state and typically a shorter lifetime than the ground state of that system. Metastable states...

A matrix-controlled display that has no information storage at the display surface.

An optical table, also known as an optical bench or an optical breadboard, is a specialized platform used in optics laboratories for mounting and aligning optical components. These tables provide a...

A plane-parallel interferometer that yields extremely high contrast over a wide range of finesse values without significantly reducing transmission.

A laser resonator in which a mode oscillating between the mirrors will converge upon the laser's longitudinal axis.

In sensitometric testing, a series of areas progressing by equal density steps (usually the increments between steps are equal to the logarithm of the square root of two). They are commonly used in...

A resonator often used for mode control in Fresnel number laser cavities that is highly vulnerable to extremely weak external sources of feedback.

3D printing, also known as additive manufacturing (AM), is a manufacturing process that builds three-dimensional objects layer by layer from a digital model. This technology allows the creation of...

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 accelerometer is a sensor or transducer that measures the rate of change of velocity of an object, or in simpler terms, it measures acceleration. Accelerometers are widely used in various...

An alexandrite laser is a solid-state laser that utilizes a synthetic crystal made from the rare earth element alexandrite (BeAl2O4:Cr3+). This crystal is capable of emitting laser light in the...

An old name for the rotating arm moving about an axis of rotation over a divided circle used to measure angles. Now the term refers to a small stadia telescope mounted over a ruler for use in...

A positively charged particle emitted from the nucleus of an unstable isotope, characterized by two protons and two neutrons. Quantitatively, the equivalent of a helium atom's nucleus.

The angle formed between a ray of light striking a surface and the normal to that surface at the point of incidence.

The second adjustable iris diaphragm in an optical system. In the common microscope condenser system, it usually is located beneath the substage condenser on a transmitted light microscope. When the...

A physical constraint, often a lens retainer, that limits the diameter of the axial light bundle allowed to pass through a lens.

An apochromat, often referred to as an apochromatic lens or apochromatic objective, is a type of optical system designed to minimize chromatic aberration. Chromatic aberration occurs when different...

An aptamer is a short, single-stranded DNA or RNA molecule that can bind to a specific target molecule with high affinity and specificity. Aptamers are often referred to as chemical antibodies due to...

Area scan, in the context of imaging and cameras, refers to a method of capturing an entire two-dimensional image in a single snapshot or exposure. Unlike line scan, which captures images one line at...

iris or adjustable radially symmetric opening used for allowing the passage of useful light

Radioactivity formed by the bombardment of stable elements by either neutrons or high-energy, charged particles under regulated conditions.

An aspheric lens is a type of lens whose surface profiles deviate from the traditional spherical shape. Unlike spherical lenses, which have a constant curvature across their surfaces, aspheric lenses...

A lens aberration that results in the tangential and sagittal image planes being separated axially.

An astronomical telescope is a type of optical instrument designed to gather and magnify light from distant celestial objects for observation and analysis. It typically consists of two main optical...

An atomic absorption spectrometer (AAS) is an analytical instrument used to determine the concentration of specific chemical elements in a sample by measuring the absorption of light at...

An atomic clock is a highly precise timekeeping device that uses the vibrations or oscillations of atoms as a reference for measuring time. The most common type of atomic clock uses the vibrations of...

Attenuated total reflectance (ATR) spectroscopy is a technique used in analytical chemistry to obtain IR spectra of samples. It is particularly useful for analyzing solid and liquid samples without...

An electronic transducer, either fixed or adjustable, that reduces the amplitude of a wave without causing significant distortion. See also beam attenuator.

Augmented reality (AR) is a technology that integrates digital information, typically in the form of computer-generated graphics, images, or data, with the real-world environment in real-time. AR...

An autocollimator is an optical instrument used for measuring small angular deviations with high precision. It operates on the principle of autocollimation, where a light source is directed onto a...

Automated optical inspection (AOI) is a technology used in manufacturing processes, particularly in electronics, to automatically inspect and detect defects or anomalies in products. AOI systems use...

A system for automatic industrial process control or measurement, consisting of an optical module for image acquisition, a segmentation processor to isolate the image from its background, and an...

Calculates the exponential growth of the least stable spatial frequency in a laser beam, and is the numerical equivalent of the nonlinear phase shift along the laser system's optical axis.

In a laser, the series resistance necessary for a stable electrical discharge.

A negative lens used to increase the effective focal length of a telescope objective.

The negative distortion that causes a square grid pattern to be imaged as barrel-shaped.

A beamsplitter is an optical device for dividing a beam into two or more separate beams. A simple beamsplitter may be a very thin sheet of glass inserted in the beam at an angle to divert a portion...