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first hand-drawn holograms, 1994
vid.puffyan.usSee http://amasci.com/holo/ Scratch-holograms can be made upon CD/DVD cases or other soft plastic using a couple of thumbtacks poked through a stick. Or get fancy and use a professional compass and black-painted polycarbonate plates. Or automate the process with a paperclip stuck into a motorized electric eraser, or a CNC mill with a drag-engraving tool.
For lots of hints, see http://amasci.com/amateur/holohint.html Best is to use a good $10 compass, soft plastic that's slightly greasy, and replace the extremely sharp compass needle with a small finishing nail. Clear plastic works fine, or place some dark paper behind it.
Are these genuine holograms? Abrasion holography or "Chatoyant holograms" employ the same physics as white-light or "rainbow" holograms invented by Stephen Benton at MIT. Benton holograms reflect light from a point source, and they do not require any interference pattern. This is why a Rainbow Hologram functions the same under any wavelength of illumination. The fringes of Benton holograms can have any spacing: even spacings much wider than wavelengths of light. Said another way: if the holograms on your credit cards are genuine holograms, then also "Scratch-holograms" must be genuine holograms. See http://amasci.com/amateur/holo3.html
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Lots more stuff at SCIENCE HOBBYIST http://amasci.com/unew.html
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Note: trolls & spammers blocked instantly. Zero tolerance.
how? what’s the principle behind it and how he can do it by hand
Compass & plexiglass or plastic CD cases, as shown in the video.
Amateur Science doesn’t seem to be hosted anymore, but here’s an archived copy of the page if you wanna read the instructions: https://web.archive.org/web/20111108131359/http://amasci.com/amateur/holo1.html & https://web.archive.org/web/20111117234715/http://amasci.com/amateur/holohint.html#0
thank you!