Building a laser sounds like a lot of fun, but it is not easy!
are several ways you can build a laser. Probably the easiest way is to
purchase a Helium Neon Laser tube and connect it to a ready made power
supply. This will make a red light that you can see, but does not
involve a lot of construction time or skill. The parts for something
like this will probably cost somewhere around $50-$75. Some resources I
found for these parts are: American Science and Surplus Herbach and Rademan
, and here is a link directly to their catalog
. You will need adobe acrobat reader to view their catalog.
you are a little bit more ambitious, and have more money you can try a
Nitrogen laser, a carbon dioxide laser, or a YAG
(yttrium-aluminum-garnet) laser. A particularly good page with
information about these is located below. Mark Csele's laser page
these end up being too difficult or expensive, I'd suggest trying,
instead, to get an already working laser and find some fun projects to
DO with it. You can easily go to Walgreens or Radio Shack and buy a
laser pointer for under $15. These contain small laser diodes which
produce a beam that is suitable for making holograms, or generally
experimenting with light. Some things I thought of to try are:
a mirror onto a speaker (right on the paper cone) and point the laser
right at the mirror. It will bounce off of the mirror and hit the wall
somewhere. Play some music through the speaker and watch what happens
to the spot.
Explore the differences between a laser and a
flash light. Try pointing them at things that are far away and
close-up. Try pointing the laser through some different lenses, maybe
through a prism and see what happens.
Cut a hole in one end of
a shoebox, Take a piece of your hair and stretch it across the hole and
glue or tape it so it is straight. Now shine the laser on the hair and
see what the light looks like on the other side of the box. You
shouldn't see just a shadow of the hair (this is called diffraction).
If your laser pointer is oval or square you may need to turn the laser
so the longer direction of the laser spot and the hair are going the
same direction. It may also help to put a piece of white paper at the
end of the box as a flat screen.
(republished on 07/28/06)