Photonics Dictionary

Brightfield refers to a type of microscopy and imaging technique in which the specimen is illuminated with a white light source, and the image is observed or captured against a bright background. In...

Brillouin microscopy is a non-invasive imaging technique that utilizes Brillouin scattering to measure the mechanical properties of materials at the microscale. This advanced optical technique...

A broadband filter is an electronic or electromagnetic device designed to pass a range of frequencies or signals within a specified bandwidth while attenuating or rejecting signals outside of that...

The behavior of microscopic solid particles suspended in a fluid, first observed by botanist Robert Brown in 1827 as a continuous random motion.

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...

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.

A microscope that allows examination of a small crystal and conveniently provides linearly polarized object and reference beams so that, by suitable orientation of an anisotropic crystal, the optical...

The production of visible light by infrared radiation whereby the light is produced by heat and not by any direct change in wavelength; the transformation is indirect.

Name originally given to the sun's infrared radiation by Sir William Herschel in his Philosophical Transactions of 1800.

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,...

An electromagnetic device used to separate isotopes of elements based on their respective masses.

Camera Link HS (high speed) is a standard developed for high-speed digital data transmission in machine vision and industrial imaging applications. It is an evolution of the original Camera Link...

A portable instrument that uses a four-sided reflecting prism or set of mirrors to create a duplicate image of an object on a horizontal sheet, on which outlines of the subject may be traced by hand.

The use of the photographic process to produce precision copies of an original image that are many times smaller in size. One of its many applications is in microcircuitry.

A resin obtained from the balsam fir, Abies balsamea, used as a lens cement.

A device that accumulates and stores electrical energy to introduce capacitance into a circuit. Basically, it is composed of two electrical conductors, separated by an insulating medium.

An instrument incorporating an infrared detector assembly, used to analyze carbon dioxide gases and in medical applications to monitor air exchange in the lungs of patients on ventilators or under...

A gas laser in which the energy-state transitions between vibrational and rotational states of CO2 molecules give emission at long IR, about 10 µm, wavelengths. The laser can maintain...

Carbonization is a process in which organic materials are heated in the absence of air, leading to the decomposition of the material and the production of carbon-rich residue. During carbonization,...

Carrier injection refers to the process of introducing charge carriers (either electrons or holes) into a semiconductor material. Semiconductors are materials with electrical conductivity between...

An image tube that functions in low-light-level conditions by virtue of its series of stacked sections wherein the output of one section becomes the input for the next.

A heterochromatic photometric process using successive comparison of similar chromaticities and the calculation of relative luminances of unlike chromaticities as the product of ratios of luminances...

A shower of cosmic rays whereby a high-energy electron produces one or more photons that convert into electron pairs, the secondary electrons producing the same effects as the primary. As the process...

A surface heat-treating process that produces a highly stressed surface. In case-hardening of glass, a plate of glass is heated almost to the softening point and then cooled quickly in a blast of...

A two-mirror lens design used in astronomical telescopes, the primary being a parabola, the secondary a smaller hyperbola. The image formed is free of spherical aberration and color and is located...

A system that uses both reflection and refraction to achieve its focal power. While the relative powers of the lenses and mirrors vary from system to system, the use of the reflective surfaces to...

A type of comparator with a telescope equipped with a cross wire mounted on a vertical sliding column. It is used to measure vertical distances on fairly near objects.

The amplitude modulation through the application of modulating voltage to the cathode circuit.

Cathode radiant sensitivity refers to the ability of a photocathode to convert incident radiant energy, typically in the form of light, into an electrical signal. Photocathodes are components used in...

A cathode is an electrode through which electric current flows out of a polarized electrical device. In different contexts, the specific role and behavior of the cathode can vary, but it generally...

A cathode-ray tube, driven by a computer, that receives impulses of information from the computer and displays it in a series of lines, circles, curves or other graphic forms to be viewed by the user.

Envelopes for cathode-ray tubes are made by blowing glass in the same manner as light bulbs. They have a fairly flat end face to carry the phosphor material applied internally.

A vacuum tube with an electron gun at one end and a fluorescent screen at the other. Electrons emitted from a heated filament are accelerated by a series of annular anodes at progressively higher...

Light that is directed or focused by means of curved reflective surfaces.

An optical system in which the only image-forming elements are curved-surface mirrors; e.g., a Cassegrain lens system.

Catoptrics is the field of optics concerned with the reflection of light from reflective surfaces such as mirrors. It encompasses the study and analysis of how light rays interact with these...

In a laser, the optical resonator formed by two coaxial mirrors, one totally and one partially reflective, positioned so that laser oscillations occur.

A CCD camera, or charge-coupled device camera, is a type of digital camera that utilizes a CCD image sensor to capture and record images. CCD cameras are widely used in various applications,...

A CCD image sensor, or charge-coupled device image sensor, is a type of electronic device used to convert optical images into electronic signals. It is a key component in digital cameras, camcorders,...