grism en · NOUN
Etymology
Blend of grating + prism.
Meanings
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A combination of diffraction grating and prism used to obtain spectra from selected parts of an image.
If this grism is placed in an ƒ/4 beam at s = 120 mm, the plate factor P ≈ 1100 Å/mm.
1987, Daniel J. Schroeder, Astronomical Optics, Academic Press, page 302:The advantage of grisms is that the same camera can be used both for imaging (without the grism) and spectroscopy (with the grism) without having to be moved.
As the name implies, grisms are a combination of a transmission grating and a prism. One common configuration uses the refraction at the grism surface to redirect nonzero diffractive orders along the original optical path.
1994, T. M. Herbst, J. T. Rayner, “First Experiences With A Solid ZnSe Grism for Near Infrared Astronomy”, in Ian S. McLean, editor, Infrared Astronomy with Arrays, Springer,, page 515:The grism usually consists of an SR transmission grating mounted on the hypotenuse of a right-angle prism.[…]Volumetric phase holographic grisms, which are capable of relatively high angular dispersions, have begun to appear.
2010, Frederick R. Chromey, To Measure the Sky, Cambridge University Press, page 382:
Forms
| Spelling | Features | Labels | Source |
|---|---|---|---|
| grisms | Number=Plur | lexicographic |
Synonyms
Translations (3)
it grisma (combination of diffraction grating and prism) · de Gitterprisma (combination of diffraction grating and prism) · fr grisme (combination of diffraction grating and prism)