
Polished glass equilateral prisms. Equilateral because each edge of the end is the same length, 32mm. Thus, as all you geometry students know, each of the angles is also the same, 60 degrees. These are school grade and are fine for decorative and demonstration. They do a nice job of diffracting light to produce a nice rainbow-like spectrum, but are definitely not up to instrumentation standards. The missing dimension, length, is shown below.
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31801 PRISM, 2" | |
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31798 PRISM, 4" | |
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31799 PRISM, 6" |
Optical grade unsilvered glass prism from Uncle's WWII tank periscopes. This one is 2-1/8" on the hypotenuse, 5-3/4" long, and 1-1/2" on each leg. They may come with small non-interfering chips or surface scratches. Great for classroom experiments or for art projects. These are a true surplus find and they will not last forever so get yours today!
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3538 MINI-MONSTER PRISM |
Nice little cubic beamsplitter prism. (Get it?) 12 x 11 x 10mm, it's painted black on (3) sides. Low transmission-about 70/30 or 80/20-but it'll be fine for classroom demos, experimentation, or perhaps souping up your fancy laser device.
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42819 BEAM SPLITTER PRISM |
Porro Abbes are small glass prisms used extensively by Uncle Sam as image-erecting systems in small optical instruments of the World War II era. They look like two small right angle prisms cemented together, but are actually made from one piece of glass. Ours have entrance faces about 5/16" square, giving them an overall length of 11/16". In final use, porro abbes would have received two facefuls of silver or aluminum to enhance reflectivity from key surfaces, but ours are plain. . . and they do have small edge chips which your fussy Uncle found offensive, and which you will barely notice in your rapture over porro abbes. Enough history. The pure bubble-free optical glass renders these prisms optical jewels suitable for window sills, earrings, and general spectral fascination. No passport needed.
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2611 PORRO ABBEY PRISMS |
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