Abbe refractometer; acoustic radiometer; acoustic resonance; active region; alpha ray; amplitude ratio; antireflective; aperture ratio; applied research; argon; aspect ratio; atomic reactor; augmented reality

ASFIR

active swept frequency interferometer radar

ASM

ampere second meter

astronomical mirror

An astronomical mirror, also known as a telescope mirror or primary mirror, is a key component of a reflecting telescope. It serves as the primary optical element responsible for gathering and...

atomic force microscope

An atomic force microscope (AFM) is a high-resolution imaging and measurement instrument used in nanotechnology, materials science, and biology. It is a type of scanning probe microscope that...

automatic current control

Automatic current control (ACC) refers to a system or mechanism designed to regulate and maintain a desired level of electric current in a circuit or device without manual intervention. This control...

automatic recording spectrograph

A direct reading spectrograph having a photomultiplier assembly in place of a photographic plate. The output from the photomultiplier assembly is received by a microammeter or a pen recorder.

axicon

An axicon is a type of optical component characterized by its conical shape and its ability to transform a collimated Gaussian beam of light into a ring-shaped beam with a gradually increasing...

B/D

blur diameter

Babinet compensator

A device containing two opposed quartz wedges of equal angle, one wedge being movable along its length by a micrometer screw. The wedges are cut so that their fast directions are along, and...

ball lens

A ball lens is a small, spherical optical component typically made of glass or other transparent materials. It is characterized by its spherical shape, with both its front and back surfaces forming...

bandgap

In semiconductor physics, the term bandgap refers to the energy range in a material where no electronic states are allowed. It represents the energy difference between the valence band, which is the...

bar

barometer

Baume scale

The scale for floating hydrometers used to measure the specific gravity of a polishing suspension. The depth of immersion is a linear function of the inverse of the density. The Baume scale is linear...

beam divergence

Increase in the diameter of an initially collimated beam, as measured in milliradians (mrad) at specified points; i.e., where irradiance is a given fraction (often 1/e2) of peak irradiance.

beam expander

A system of optical components designed to increase the diameter of a radiation beam. Usually an afocal system.

beam profiler

A device that measures the spatial distribution of energy perpendicular to the propagation path of a radiant beam. An energy or power meter is typically used to monitor the amount of light passing...

beam profiling

Beam profiling is a technique used to characterize and analyze the spatial intensity distribution of a laser beam. It involves measuring and visualizing how the optical power or intensity is...

beam waist

That point in a Gaussian beam where the wavefront has a curvature of zero and the beam diameter is a minimum.

Bessel functions

Two formulas used in diffractometer analysis, the first giving the individual diffraction patterns of each aperture, the second representing the constant of the degree of an incoherent circular...

blaze height

Blaze height typically refers to a parameter in the context of diffraction gratings, which are optical devices consisting of a series of closely spaced parallel grooves or slits. The blaze height is...

blue diode laser

A blue diode laser is a type of semiconductor laser that emits light in the blue wavelength range of the electromagnetic spectrum, typically between 400 and 500 nanometers. Diode lasers are compact,...

bolograph

A bolometer that serves to record. The photographic record formed by the bolometer may be called bolograph or bologram.

Bragg cell -> acousto-optic modulator

An acousto-optic modulator (AOM) is a device that utilizes the acousto-optic effect to modulate the amplitude, phase, frequency, or polarization of a laser beam or other coherent light source. It...

Brewster's fringes

The fringes used in the Jamin interferometer and produced by light that has been internally and externally reflected by two plane-parallel plates, inclined toward each other at a small angle.

Bunsen screen

A photometer screen that contains a diaphragm of paper or parchment with a translucent central spot of oil or paraffin.

C-mount

A standard lens interface initially made for 16mm movie cameras and now used primarily on closed-circuit television cameras. It is a 1-in.-diameter, 32-thread-per-inch interface with a...

cadmium lines

The three lines in the spectrum of cadmium that have the purest radiations and that were first used by Michelson to calculate the standard meter.

calorimetry

Calorimetry is a branch of science that involves the measurement of heat flow in physical or chemical processes. It encompasses various techniques and instruments used to quantify heat transfer,...

candela

SI unit of luminous intensity. It is defined as one sixtieth the normal intensity of one square centimeter of a blackbody at the solidification temperature of platinum. A point source of one candela...

Photonics Dictionary