theSpectrum
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Lecture Demonstration Specialist beehler@physics.utah.edu
Adam Beehler’s Demolicious Physics presents:
TRICKS YOU DIDN’T KNOW YOU COULD DO WITH
LASERS
Laser Spirograph
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(Lissajous Patterns*)
I think I first saw such an arrangement at the Little Shop of Physics outreach program at Colorado State University. Taking a laser pointer and aiming it at a mirror, the beam is directed toward a second mirror, and then on to a third mirror. Each mirror is mounted onto a little motor that can be controlled by a switch (both items easily found at any hobby supply store). In this way, one rotating mirror can reflect the beam in one direction while another mirror can reflect that same beam in another direction. Due to the persistence of vision of our eyes, we see the beam drawn around in wonderful patterns on a screen. I have personally made a little portable version with the components mounted on a board. It was a big hit one campout when I projected cool, moving patterns onto the trees at night.
I was contemplating some of the cool things that could be done by folks with common, everyday materials. It was not long before I remembered the laser. What was non-existent in the not too distant past, is now ubiquitous & necessary for so many other applications. To many people, a laser is considered just a toy. So, here are a few activities that I have enjoyed over the years that are made possible, or easier, with a simple laser pointer, found at any office supply store. (Laser pointers are less expensive online, on sites like Amazon.com)
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