Laser for laser spirograph show

Hello, to everyone. I am new to this forum and I d like some information.

I m planning to make my first laser spirograph. I know some things about lasers and i have seen some tutorials about making a laser spirograph. I have heard that a laser of less than 5mW is safe enough for the eyes. However, I wonder if a 1mW or even a 5mW laser would look good. I mean will the beam be visible in a dark environment? I am afraid of buying a more powerful laser due to safety reasons.

Thank you in advance. I hope there is not a similar thread (i searched the first pages and didnt find nothing).

Usually for such low powers you will want some source of smoke (a fog machine or other methods).

Just use 5mws of 532nm (green), it will be the most visable for the power due to its wavelenth (yes will vary, but in general to most people 532nm is the most visable per mw), and with a combination of smoke, you can get your effects without needing to go into high powers.

hope that helps you out.

And welcome to LPF.

I built a 4 motor spyro (still need to make a thread with the completed product) and used a 50mW module. I project on dark surface and haven't any issues.

You could wire an external pot to control the brightness.

to me spiro is all about the image projected and not so much about the beams so fog/smoke is not really needed. But total darkness allows even low powered laser make an enjoyable spiro. 4 motors are better than 3 and reverse makes more patterns and the ability to change the speed of all motors make even more possibilities. Add the ability to change color of the laser is better still.


Kevlar plz do make that tut for the beginners.
hak

I played with my spiro using 5mW red, green, and violet. And they all looked good. You should have no problem seeing it in a dark room, no smoke needed.

Old home movie screens can be obtained at many thrift shops for very little. These work great for low powers BUT if you use one with higher powered lasers they can work too well. So just a white or other light color wall and/or ceiling is fine.

Tip- keep your mirrors very close to each other- put the one with the smallest mirror first and the largest mirror last. The idea is to keep all the laser on the mirrors -not off the edges.

In this pic you can see a spiro made by Ken.
its in post #19
the spiro is towards the back left corner- note how close the mirrors are to each other.

http://laserpointerforums.com/f42/white-laser-kit-rgbr-aixiz-63256.html