Electrical – Best way to wire multiple laser modules

Chemistry dictates that lasers often produce light in the infrared spectrum. Popular neodymium-doped lasers produce light at 1064 nm, which is well into the infrared range. To get around this, frequency doublers are employed, which halve the wavelength to 532 nm, which is a green light.

For this reason, it's unsurprising that your laser emits IR light. The frequency doublers aren't perfect; a significant amount of IR gets through. Good lasers will filter this out, cheap ones won't bother. If this is important to you, use a reputable manufacturer (like the ones on Digikey) and verify that they at least claim to use IR filters.

Unforrunately, no -- not if you want them to work correctly.

Laser diodes are somewhat similar to light emitting diodes (technically they are....) in that they have a particular diode I-V curve.

If anything, you would at least want to use a LED driver if not a constant current source. In that case you could wire a few in series.

Without a datasheet for your lasers, design is going to be a bit more seat-of-the-pants.

I recommend http://www.linear.com/product/LT3598 as a laser driver. It will require circuit design, soldering, and more parts I'm afraid. Still if you work hard it will make a great costume @ the end of October!