grism
nounEtymology Blend of grating + prism.
1
A combination of diffraction grating and prism used to obtain spectra from selected parts of an image.
- 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.
- 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:
2 more examples
- 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: