Using inexpensive and easy to get parts, build a 7 colour, including of course white, hand held laser.The following parts will be enough to build a bare, 7 selectable colour laser, it is up to you to make the housing of your choice. This could easily be built into a project box but the author wanted a hand held pointer.
You will need to remove all of the optics EXCEPT the 2 splitter cubes and the turning mirror.The three holes circled in red below need to be drilled out to 5.0mm dia.Saw the beam splitter section off, cut along the green line. Cut out the turning mirror.
When you assemble the modules the bezel needs to be screwed tight up to the front half of the module metal to metal, no plastic lens nut showing at exactly the focus point, this is quite easy for the blue, it is just a case of getting the lens the right distance into the bezel.
The red will need a thin washer to take up the gap, I used a ring of solder squashed to the right thickness in a vice to get it right
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