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Meadowlark Optics - Wave Plates 6/24 LB 2024
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380 terms

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disc calorimeter
A device that provides simple and reliable laser power and energy measurement. Essentially a heat flux sensor producing an output proportional to the power, rather than the energy input.
disc colorimeter
A colorimeter using a spinning disc made of different colored sections for colorimetric analysis.
disc laser
A laser having a rod that is a stacked array of discs immersed in a transparent flowing coolant fluid. In this way, the cooling rate is increased, the temperature gradients are basically parallel to...
disc telescope -> coronagraph
A telescope in which a mask occults the solar disk, generating an artificial eclipse and allowing observation and recording of the sun's corona.
discharge lamp -> electric-discharge lamp
A lamp that uses the transmission of an electric current through a gas or vapor to produce illumination. Neon, mercury and argon lamps are examples of electric-discharge lamps.
discontinuously reinforced aluminum
A composite derived from aluminum alloy powder and silicon carbide, used as an optical substrate in air- and spacecraft applications. It is as light as aluminum but exhibits greater strength and...
discrete
An individual circuit component, complete in itself, such as a resistor, diode, capacitor or transistor. It is used as an individual and separable circuit element.
discrete cosine transform
A mathematical transformation used in image and video compression that changes two-dimensional representation of data into data defined by the frequency content. Adapted in JPEG and MPEG standards.
discrete spectrum
A spectrum of component wavelengths whose values are separate from each other.
discrimination
The degree to which a vision system is capable of sensing differences in light intensity between two regions.
discriminator
A circuit incorporated into counter systems that records only pulses that have amplitudes between two preselected limits.
dislocation
The region of distorted atom configuration formed between the displaced and normal areas in a crystal when part of the crystal is displaced tangentially.
dispersing prism
A prism or series of prisms used to disperse a beam of radiant energy of mixed wavelengths into its spectral components.
dispersion
Dispersion refers to the phenomenon where different wavelengths (colors) of light travel at different speeds when passing through a medium. This variation in the speed of light for different colors...
dispersion filter
A complex filter that uses polarization and interference to transmit light that is nearly monochromatic.
dispersion formula
All formulas that present the index of refraction as a function of a wavelength of electromagnetic radiation. Also called dispersion equation, Cauchy formula, Hartmann formula.
dispersion-flattened single-mode fiber
A type of glass optical fiber that provides low pulse dispersion over a broad portion of the light spectrum and as a result can operate at 1300-nm and 1550-nm wavelengths simultaneously.
dispersion-limited operation
Operation in which the dispersion of a pulse limits the distance between repeaters in optical systems. Waveguide and material dispersion can make recognition of a pulse impossible.
dispersion-shifted fiber
A dispersion-shifted fiber (DSF) refers to a type of optical fiber designed to minimize the effects of chromatic dispersion, which is the phenomenon where different wavelengths of light travel at...
dispersive correlation spectrometer -> mask spectrometer
Instrument that uses absorption spectroscopy to detect gases in planetary atmospheres. Dispersed incoming radiation is transmitted to one or more sampling elements, or masks, before reaching the...
dispersive lens -> diverging lens
A diverging lens is a type of lens that causes parallel rays of light to spread out or diverge. It is thinner in the center than at the edges and is commonly referred to as a concave lens. The most...
dispersive power
A measure of the dispersive properties of a glass. The relative dispersion is defined as: where C, D, and F refer to the material's index of refraction at the three chief Fraunhofer lines in the...
display
The observable illustration of an image, scene or data on a screen such as a console or cathode-ray tube, seen as a graph, report or drawing.
display console
A visual display used with a computer to give access to the many elements of data as an array of points. With the display console, an operator may check information in the computer and change it if...
display primaries -> receiver primaries
Also known as display primaries. Colors formed by a television receiver that are of constant chromaticity and variable luminance, and that, mixed in certain proportions, form other colors. Red, green...
dissector
In optical character recognition, the mechanical or electronic transducer used to detect the level of illumination present in the various portions of an illuminated sample region.
dissonance
In optics, the production of maxima and minima by the superimposition of two sets of interference fringes from light of two different wavelengths.
distal end
The end of an optical fiber farthest from the source of illumination.
distance of distinct vision
The near-point distance of the normal eye. The value of 10 in. or 25 cm is normal. This value is used in evaluating the designated magnification of a simple magnifier or eyepiece.
distance-luminosity relationship
In astronomy, the relation that states that the intensity of a star's visible radiation is inversely proportional to the square of the distance from which it is viewed.
distortion
A general term referring to the situation in which an image is not a true-to-scale reproduction of an object. The term also is used to connote the temporal alteration of the signal's waveform shape....
distortion-limited operation
The limitation on performance imposed by the distortion of a received signal rather than its amplitude or power.
distributed Bragg reflector
A device similar to distributed feedback lasers in construction and operation, but in which the period grating that produces feedback is removed from the gain region to simplify fabrication. The...
distributed feedback laser
A distributed feedback laser (DFB laser) is a type of semiconductor laser diode designed to emit coherent, narrow-bandwidth light with precise control over the wavelength. It achieves this through a...
distribution temperature
Temperature of the blackbody having a spectral power distribution approximately proportional to the test source at all wavelengths; it follows that the two have the same chromaticity.
dithering
In image processing, modifying the dot that forms the image in order to simulate a series of gray tones.
diurnal aberration
Atmospheric aberration caused by the Earth's rotation; the degree varies from 0 at the poles to a maximum of 0.31 s of arc at other locations.
diurnal phase shift
Phase shift in electromagnetic signals caused by daily variations in the ionosphere, often during sunrise or sunset.
divergence
1. In optics, the bending of rays away from each other. 2. In lasers, the spreading of a laser beam with increased distance from the exit aperture. Also called beam spread. 3. In a binocular...
divergent lens -> diverging lens
A diverging lens is a type of lens that causes parallel rays of light to spread out or diverge. It is thinner in the center than at the edges and is commonly referred to as a concave lens. The most...
divergent-meniscus lens
A lens with one surface convex and the other concave, the latter having the greater curvature. It also is known as a diverging meniscus lens.
diverging lens
A diverging lens is a type of lens that causes parallel rays of light to spread out or diverge. It is thinner in the center than at the edges and is commonly referred to as a concave lens. The most...
divided circle spectrometer
A spectroscope having a divided circle and a means for the rapid reversal of prisms for the measurement of refractive index of the prism for a specific wavelength.
divided slit scan
A scanning technique in optical character recognition in which an array of photocells is used to scan each character to determine its horizontal and vertical characteristics.
Dobson spectrophotometer
A spectrophotometer that measures the amount of ozone in the atmosphere through a comparison of solar energy at two wavelengths in the ozone's absorption band. This comparison is achieved by...
Dogmar/Aviar lens
A general-purpose lens, also known as the Celor lens, used widely in photography and commercial processing; it has the form of a triplet with a split flint element.
doma
A primitive crystal possessing two plane surfaces that form a dihedral angle bisected by another plane surface.
dome -> optical instrument dome
A dome-shaped structure used for some optical instruments in place of a flat window. The transparent material should be of good quality and the hemispherical surfaces should be concentric.
dominant wavelength
A single wavelength of light that matches the color of a given sample when combined in suitable proportions with white light and a suitable adjustment of intensity.
donor
An impurity in a material that is capable of inducing electrical conduction in that material by transferring an electron to the conduction band.

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