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prisms

2 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

Prism \Prism\ (pr[i^]z'm), noun [L. prisma, Gr. pri'sma, fr. pri'zein, pri'ein, to saw: cf. F. prisme.]

1. (Geom.) A solid whose bases or ends are any similar, equal, and parallel plane figures, and whose sides are parallelograms.

Note: Prisms of different forms are often named from the figure of their bases; as, a triangular prism, a quadrangular prism, a rhombic prism, etc.

2. (Opt.) A transparent body, with usually three rectangular plane faces or sides, and two equal and parallel triangular ends or bases; -- used in experiments on refraction, dispersion, etc.

3. (Crystallog.) A form the planes of which are parallel to the vertical axis. See {Form}, noun, 13.

{Achromatic prism} (Opt.), a prism composed usually of two prisms of different transparent substances which have unequal dispersive powers, as two different kinds of glass, especially flint glass and crown glass, the difference of dispersive power being compensated by giving them different refracting angles, so that, when placed together so as to have opposite relative positions, a ray of light passed through them is refracted or bent into a new position, but is free from color.

{Nicol's prism}, {Nicol prism}. [So called from Wm. Nicol, of Edinburgh, who first proposed it.] (Opt.) An instrument for experiments in polarization, consisting of a rhomb of Iceland spar, which has been bisected obliquely at a certain angle, and the two parts again joined with transparent cement, so that the ordinary image produced by double refraction is thrown out of the field by total reflection from the internal cemented surface, and the extraordinary, or polarized, image alone is transmitted. Prismatic

From WordNet (r) 3.0 (2006) [wn]:

prism

noun

1: a polyhedron with two congruent and parallel faces (the bases) and whose lateral faces are parallelograms

2: optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an image [syn: {prism}, {optical prism}]


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In the interest of FULL DISCLOSURE, there is a particularly interesting partial SCREENSHOT of the home page here.

I used Abduction! for Firefox or Webpage Screenshot for Chrome to get this series of SCREENSHOTS.

Electronic Frontier Foundation Golden Key Campaign

I don't want Uncle Sam having my SIM Card PRIVATE keys.

SIM Card
Golden Key
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This is a Thumbnail of the particularly interesting partial SCREENSHOT above. The really fine print is not legible, but if it's slightly oversized, it can be read in the thumbnail. Generally, in the thumbnail, you can't read the fine print. In the fine print I say that I'm using all of these copyrighted and trademarked seals and logos and images without the permission of the intellectual property owners. I am stating that these parties are not endorsing my website and that I am not related to them in any capacity. I state that my ideas and suggestions might affect them or might be related to their industries or areas of interests and that I am addressing these parties and institutions.

I allow commentary on the home page and variants of "Cool." I may not stay with DISQUS but right now it suits me - at least in these places.

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Thursday, March 5, 2015 6:43:49 PM Coordinated Universal Time (UTC)

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