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Optimax Systems, Inc. - Optical Components & Systems 2024 LB
Photonics Marketplace
623 terms

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secondary x-rays
X-rays emitted by a substance that formerly has been exposed to x-rays. The properties of the substance determine the frequency of the rays.
section converter
An arrangement of optical fibers in a bundle whereby the geometric configuration of the input end differs from that of the output end without changing the total area; for example, a circular bundle...
sector disc
A disc, having opaque and transparent sectors or sectors with unlike reflectances, that is rotated at a specific rate to form a continuous response to the average energy transmitted or reflected by...
Seebeck effect
Characteristic of dissimilar metals in thermoelectric solar cells whereby separate junctions exhibiting distinct temperatures transform incident voltage into a current.
seed
1. In glass, a solid inclusion having a small diameter. 2. A particular, single crystal that, after undergoing the Czochralski method, evolves into large single crystals.
segment
In multifocal spectacles, a term used to denote glass with a high refractive index that has been fused to the blank and ground to a curvature, resulting in added power.
segment height
In a bifocal spectacle lens, the vertical measurement of distance from the uppermost borderline of the bifocal segment to the lower lens edge.
segment width
In spectacle lenses, the lateral measurement of a multifocal segment at its maximum width.
segmentation
In optical character recognition, the method of dividing a string of characters into separate, distinct characters.
Seidel aberrations
Seidel aberrations refer to a set of monochromatic aberrations in optical systems, named after the German mathematician and physicist Ludwig von Seidel. These aberrations describe deviations from...
selective laser melting
Selective laser melting (SLM) is an additive manufacturing (AM) or 3D printing technology that belongs to the powder bed fusion category. SLM is primarily used for metal additive manufacturing, where...
selective reflection
The reflection in different amounts as a function of wavelength, as a result of absorption and scattering, leading to color effects if occurring in the visible wavelength region.
selective transmission
Transmission in different amounts as a function of wavelength, as a result of absorption and scattering, leading to color effects if occurring in the visible wavelength region.
selenium cell
A photoconductive cell consisting of a layer of selenium on a substrate whose electrical resistance varies with the illumination falling on the cell. Selenium cells have been replaced largely by...
selenology
That branch of astronomy concerned with the study of the moon's physical characteristics.
self-absorption
In optical emission spectroscopy, the reduction in radiant power in the central portion of spectral lines arising from the selective absorption by the cooler outer vapor of the source envelope of...
self-electro-optic effect device
An optically bistable device used for photonic switching, constructed of a multiple quantum well biased by an external voltage, which creates an external field that shifts the wavelength of the onset...
self-generating barrier layer cell -> photovoltaic cell
A photovoltaic cell, commonly known as a solar cell, is a semiconductor device that directly converts light energy into electrical energy through the photovoltaic effect. The photovoltaic effect is...
self-heating
Heating that results from the dissipation of energy.
self-luminous light source
Any material that derives its energy from chemically or electrically induced reactions; isotope or radium excitation is used to form the glow in luminescent watch or clock hands.
self-phase modulation
Self-phase modulation (SPM) is a nonlinear optical phenomenon that occurs when an intense laser beam passes through a medium, causing a change in the phase of the light due to its interaction with...
self-reversal
The extreme case of self-absorption.
SELFOC fiber
Derived from "self-focusing,'' Nippon Sheet Glass Co. (NSG) of Japan's trade name for graded-index fiber rods with parabolic index profile, suitable for use as cylindrical microlenses.
SELFOC lens -> SELFOC fiber
Derived from "self-focusing,'' Nippon Sheet Glass Co. (NSG) of Japan's trade name for graded-index fiber rods with parabolic index profile, suitable for use as cylindrical microlenses.
Sellmeier's equation
An equation that uses the wavelength of light passing through a medium, along with a set of coefficients, to calculate the medium's index of refraction. The coefficients, called Sellmeier...
semiconductor
A semiconductor is a type of material that has electrical conductivity between that of a conductor and an insulator. In other words, semiconductors have properties that are intermediate between...
semifinished blank
A formed piece of glass, one surface of which has been ground and polished to the required curvatures.
semifinished
A term used to describe a spectacle lens or blank with one surface totally finished.
semilenticular screen
A projection screen having vertical ribs or flutes set into a plastic surface.
semitransparent and p-phase annular aperture
An aperture consisting of a semitransparent central region whose amplitude transmittance only is varied, and the relative phase difference between the central and annular region is fixed as p -...
semitransparent photocathode
A photocathode that receives radiation from one side and emits a photoelectric current from the opposite side.
Senarmont compensator
A type of compensator for use with a microscope and consisting of a quarter-wave plate in a fixed position and a rotatable analyzer.
Senarmont prism
A polarizing beamsplitting prism similar in design to the Rochon prism. However, the Senarmont transmits the extraordinary ray without deviation and deviates the ordinary ray due to the orientation...
sensitivity
In a radiation detector, the ratio of the output to the input signal.
sensitized fluorescence
The optical energy transfer between ions of differing atoms.
sensitometer
An instrument for determining the sensitivity of a photographic film to light. The film is given either a stepped exposure or a continuously varied exposure; after processing, the density is measured...
sensitometry
Primarily the measurement of photographic sensitivity of certain materials such as photographic film. It refers to the measurement of the response of photographic materials, after exposure, to forms...
sensor
1. A generic term for detector. 2. A complete optical/mechanical/electronic system that contains some form of radiation detector.
separate absorption and multiplication region avalanche photodiode
An avalanche photodiode in which the light-absorbing area is a low-bandgap material and the PN junction is placed in an area of high-bandgap material, reducing dark current and increasing gain.
separation filters
Three filters used in making a color print of a color negative, red, green and blue-violet, respectively. Each filter transmits about one-third of the visible spectrum onto the print.
sequence camera
A type of motion-picture camera in which single frames are photographed either automatically at a predetermined rate (as slow as one frame per minute or hour), or whenever the operator presses a key....
sequential color transmission
With respect to television, the transmission of the signals that originate from variously colored parts of an image in a particular sequential order.
sequential scanning
Raster scanning process like that of television: each line is scanned successively.
serial scanning -> rectilinear scanning
The scanning of a region in a given sequence of slender, straight parallel strips.
serial transmission
A mode of data transmission whereby each bit is generated in sequence on a single carrier.
serioscopy
A variation of tomography, which is a means of visualizing any one of a large set of parallel planes in the patient. A series of x-ray pictures taken from different angles results in developed...
serpentine bend mode filter
A device used in measuring attenuation in optical fiber. The loss caused by the bends in a short reference length of fiber approximates that of a much longer fiber under test.
servomechanism
A closed-loop system that is constantly adjusted in response to input signals generated within the system.
servomotor
A type of motor that acts as the control element in a servomechanism. It is powered by an amplifier circuit and drives the load with linear or rotary motion.
sextant
A handheld navigational instrument used to measure the elevation angle of celestial bodies such as the sun. An image of the sun is viewed through a small telescope via two plane mirrors so that any...

Photonics DictionaryDefinitionsS

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