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Videology Industrial-Grade Cameras - Mini Color Camera 2024 HP

47 terms

Photonics Dictionary: V

Clear All Filters x HOEs x V x
V-number -> normalized frequency

Also referred to as the V number in fiber optics; the normalized frequency is a dimensionless quantity, denoted by the symbol V, given by: where a is waveguide core radius, l is wavelength in vacuum,...

V-value -> Abbe constant

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...

vacuum

In optics, the term vacuum typically refers to a space devoid of matter, including air and other gases. However, in practical terms, achieving a perfect vacuum, where there is absolutely no matter...

vacuum chamber

A vacuum chamber is a sealed enclosure from which air and other gases are removed to create a low-pressure environment, typically close to or at a complete vacuum. These chambers are often...

vacuum etching

Also known as cathodic etching. Surface etching achieved by bombarding an evacuated surface with gas ions.

vacuum gauge

A gauge designed to measure the degree of vacuum in an evacuated vessel. A simple U-tube containing mercury is adequate for low vacua, but for high vacua other methods must be employed. See McLeod...

vacuum phototube

A phototube that functions within a vacuum and thus eliminates the effects of gaseous ionization on its electrical properties.

vacuum ultraviolet detector

A device that serves to detect the presence of vacuum ultraviolet radiation. It may be photographic film, a thermopile, ion chamber, vacuum photodiode, photomultiplier or channel electron multiplier.

vacuum ultraviolet radiation

Radiation whose spectrum runs between 100 and 300 nm. Any work with these wavelengths requires evacuated equipment.

vacuum ultraviolet spectroscopy

A method of spectral analysis using wavelengths between 100 and 300 nm that utilizes both emission and absorption techniques.

vapor degreasing

A method of cleaning and drying coated optical components. The cooled parts are placed in a container above a boiling solvent, whose vapors condense on the parts. When the parts reach the temperature...

vapor-phase epitaxy -> epitaxy

A well controlled thin films technique for growing films with good crystal structure in ultra high vacuum environments at very low deposition rates. Epitaxy methods are well known for the growing of...

variable-focus condenser

An Abbe condenser in which the upper lens element is fixed. The lower lens may focus the illumination between the elements so that it emerges from the fixed lens as a large-diameter parallel bundle....

VCSEL

vertical-cavity surface-emitting laser

velocity modulation laser spectroscopy

A method of measuring negatively charged phase ions using a color-center or lead-salt diode laser.

venetian-blind effect

Short-distance scattering of light in holography caused by random index inhomogeneities and the developing index that interferes with the incident beam, thus recording a hologram of the scattered...

Verdet constant

A factor of an equation of the Faraday effect, which is the rotation of the plane of light polarization by transparent materials in a magnetic field. Therefore, in the equation: where a...

vertical air photograph

An aerial photograph produced when the optical axis of the camera is perpendicular to the surface below.

vertical blanking

With respect to a television system, a pulse transmitted at the end of each field to break off the cathode-ray beam as it begins the next field.

vertical external cavity surface-emitting laser

A laser that has a surface-emitting semiconductor gain element coupled to an external mirror designed to complete the laser resonator. VECSELs can be electrically or optically pumped. The extended...

vertical leveling mirror

A two-sided mirror suspended by a pendulum mechanism. An autocollimator set normal to such a mirror surface will, by definition, have its optical axis set horizontal.

vertical resolution

In television system specifications, the number of parallel horizontal black and white lines of equal thickness, that can be resolved from top to bottom of the raster. (One line equals either a black...

vertical-cavity laser diode

A type of surface-emitting laser diode that uses dielectric mirrors to produce surface emission. The laser cavity is established in a vertical direction with respect to the plane of the active region.

vertical-cavity surface-emitting laser -> vertical-cavity laser diode

vertical-deflection electrodes

Two electrodes that shift the electron beam vertically on a cathode-ray tube screen using electrostatic deflection.

via

In integrated circuits, a pathway, hole, or other passage through the substrate.

vibrational circular dichroism

Vibrational circular dichroism (VCD) is a spectroscopic technique used to probe the chiral properties of molecules. It measures differences in the absorption of left- and right-circularly polarized...

vibrational spectroscopy

Vibrational spectroscopy is a type of spectroscopy that involves the study of the vibrational states of molecules. It is used to obtain information about the molecular structure, bonding, and...

vibrational transition

A vibrational transition refers to a change in the vibrational energy of a molecule. Molecules consist of atoms that are connected by chemical bonds, and these atoms are not stationary but are in...

vibronic transition

A type of change in the energy levels of molecules in a laser that results in lasing action. Vibronic transitions are those between one electronic level and another.

video subtractor -> image comparison

A method used in imaging to detect subtle differences between two apparently similar pictures. It can be achieved by superimposing the negative of one photograph over a contact print of another, by...

videodisc

A disc whose surface contains recorded digital data at high-packing densities arranged in concentric rings. The data, representing video frames, are both recorded and read by a laser beam.

vidicon

A small television tube originally developed for closed-circuit television. It is about 1 inch in diameter and 5 inches long. Its controls are relatively simple and can be operated by unskilled...

viewing filter

A filter, pale purple in color, used in black and white photography to display the brightness values of a subject being recorded on film.

vignetting

In an optical system, the gradual reduction of image illuminance as the off-axis angle increases, resulting from limitations of the clear apertures of elements within the system.

virtual histology

Virtual histology refers to the use of digital technology and computational methods to simulate or recreate histological images and structures without the need for traditional physical slides and...

virtual image

An image that is formed when rays emerging from an optical system are diverging from the optical axis. The virtual image is formed where the bundle of diverging rays appear to intersect each other...

visibility meter

1. An instrument used to determine the visual range in an environment. 2. A type of photometer that artificially reduces an object's visibility to threshold limits and records the quantity of...

vision-transformer networks

Vision transformer (ViT) networks are neural network architectures that apply the Transformer architecture, originally developed for natural language processing, to the task of processing visual...

visual photometer

A photometer that permits visual comparison of the luminance of two surfaces.

visual storage tube

An electron tube that stores and visually displays information by means of a cathode-ray-beam-scanning and charge-storage mechanism.

voltage contrast analysis

A nondestructive testing method for very large scale integration circuits, using a scanning electron microscope to monitor changes in the electronic state of the chip as it is fed test voltages while...

volume Bragg gratings

Volume Bragg gratings (VBGs) are specialized optical elements that consist of periodic variations in refractive index throughout the volume of a transparent material, typically a photosensitive glass...

volume hologram

A three-dimensional hologram.

volumetric imaging

Volumetric imaging refers to the capture, visualization, and analysis of three-dimensional (3D) information from a volume of space. Unlike traditional two-dimensional (2D) imaging, which provides...

vortex phase plate

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...

VSTEP

vertical to surface transmission electrophotonic device

Photonics DictionaryV

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