An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 13 Search : grating
blazed grating
  توری ِ بلیزی   
turi-ye belizi

Fr.: réseau échelette   

A → diffraction grating ruled appropriately so that a large proportion of the diffracted light is concentrated into a few, or even a single → order of interference.

Blazed, adj. of → blaze; → grating.

Turi, noun from tur "a net, a fishing net;" belizi adj. from beliz, → blaze.

concave grating
  توری ِ کاو   
turi-ye kâv (#)

Fr.: réseau concave   

A → diffraction grating ruled on a concave spherical mirror that eliminates chromatic aberration and transmits regions of the spectrum, such as the ultraviolet, which is not transmitted by glass lenses.

concave; → grating.

diffraction grating
  توری ِ پراش   
turi-ye parâš (#)

Fr.: réseau de diffraction   

An optical device containing thousands of very fine parallel grooves which produce interference patterns in a way which separates out all the components of the light into a spectrum.

diffraction; → grating.

echelle grating
  توری ِ نرده‌ای   
turi-ye narde-yi (#)

Fr.: réseau à échelle   

A diffraction grating in which the groves are relatively widely spaced and serves to provide high resolution and dispersion.

Echelle, from Fr. échelle "ladder," , from O.Fr. eschele, from L. scala "ladder;" → grating.

Turi, → grating; nardé, contraction of nardebân "ladder; échelle."

grating
  توری، ~ ِ پراش   
turi, ~ -e parâš (#)

Fr.: réseau   

Same as → diffraction grating.

M.E. grating, M.L. grata "a grating," variant of crata, from crat-, stem of cratis "wickerwork."

Turi, from tur "fishing net, net, snare," variants târ "thread, warp, string," tâl "thread" (Borujerdi dialect), cognate with tanidan, tan- "to spin, twist, weave" (Mid.Pers. tanitan; Av. tan- to stretch, extend;" Skt. tan- to stretch, extend;" tanoti "stretches," tantram "loom;" tántra- "warp; essence, main point;" Gk. teinein "to stretch, pull tight;" L. tendere "to stretch;" Lith. tiñklas "net, fishing net, snare," Latv. tikls "net;" PIE base *ten- "to stretch").

grating angle
  زاویه‌ی ِ توری   
zâviye-ye turi (#)

Fr.: angle de réseau   

The angle between the incident optical beam and the normal to the grating. It is the angle to which the grating must be set to place the desired wavelength at the center of the detector.

grating; → angle.

grating efficiency
  کار‌آیی ِ توری   
kârâyi-ye turi (#)

Fr.: efficacité de réseau   

The measure of the light intensity diffracted from a grating.

grating; → efficiency.

grating groove
  شیار ِ توری   
šiyâr-e turi (#)

Fr.: trait du réseau, sillon ~ ~   

One of thousands of long, narrow indentations in the surface of a → diffraction grating.

grating; → groove.

holographic grating
  توری ِ هرونگاریک   
turi-ye harunegârik

Fr.: réseau holographique   

A → diffraction grating produced from a series of constructive → interference fringes. The fringes, whose intensities vary in a sinusoidal pattern, correspond to the grooves of the grating. They are recorded on a photosensitive substrate and subsequently treated using a chemical procedure. Since the grooves are created by the interference of light, such a grating is free from the random and periodic errors present in → ruled gratings.

holographic; → grating.

integrating factor
  کروند ِ درستالنده   
karvand-e dorostâlandé

Fr.: facteur intégrant   

A function that converts a → differential equation, which is not exact, into an → exact differential equation. This is done by multiplying all terms of the original equation by the integrating factor.

integrate; → factor.

objective grating
  توری ِ بر‌آختی   
turi-ye barâxti

Fr.: réseau-objectif   

A diffraction grating placed over the aperture of a telescope in order to produce spectra of all the objects in the field of view.

objective; → grating.

ruled grating
  توری ِ شیاردار   
turi-ye šiyârdâr

Fr.: réseau à traits   

A → diffraction grating with a series of grooves that have been ruled on a reflective surface with a diamond tool mounted on a ruling machine. Ruled gratings may have triangular or trapezoidal groove profiles, whereas → holographic gratings usually have sinusoidal groove profiles.

Ruled, → rule; → grating.

Turi, → grating; šiyârdâr "having grooves," from šiyâr, → groove, + -dâr "having, possessor," → property.

transmission grating
  توری ِ تراگسیلی   
turi-ye tarâgosili

Fr.: réseau par transmission   

A diffraction grating that has grooves ruled onto a transparent material so that a beam of light passed through the grating is partly split into spectral orders.

transmission; → grating.