Rgb spatial filter. One blade pinhole method

[jors]

Today, with lots of technology, we return to talk about LASERS & drilling RAZOR BLADES, like Mr. Maiman did with first LASER. They measured the pulsed laser power by "Gillettes"...this is surprising
http://www.osa.org/en-us/about_osa/n...uaries/maiman/
Thanks for the calculator!

[krazer]

Also worth mentioning is that there are a few people on the forum who are capable of cutting pretty decent quality pinholes. Macona comes to mind with his 355nm rig, if you want some really fancy holes and do not mind waiting a few months I can do a run on one of the picosecond or femtosecond lasers I run at MIT. I suppose it could be interesting to do 'variable' pinholes, take a strip of SS and cut a few sizes into it.

The plan of doing it with your own laser is a good one, just be careful the edges of the cut will probably be pretty poor when cut using a CW laser and no gas assist. However, this may actually help the quality of your farfield beam, having a jagged edge helps scramble any diffraction effects (airy rings, etc) that would normally come from a good clean aperture.

You can also always just couple your projector into a piece of fiber and then have a prefect* overlap between your colors and perfectly round beam. *only limited by the quality of the lens you use for collimation and variation of the mode field size for different wavelengths, both of which should be pretty negligible. The beam parameter product for a 62um telecom fiber is really not that bad when you compare to the starting beam quality of a knife-edged projector. Plus you get a free fiber remote launch for your projector

[swamidog]

i was able to blast a pin hole into very thin steel shim stock with my 60W co2 laser, but the edge quality wasn't as good as i would like.

Also worth mentioning is that there are a few people on the forum who are capable of cutting pretty decent quality pinholes. Macona comes to mind with his 355nm rig, if you want some really fancy holes and do not mind waiting a few months I can do a run on one of the picosecond or femtosecond lasers I run at MIT. I suppose it could be interesting to do 'variable' pinholes, take a strip of SS and cut a few sizes into it.

The plan of doing it with your own laser is a good one, just be careful the edges of the cut will probably be pretty poor when cut using a CW laser and no gas assist. However, this may actually help the quality of your farfield beam, having a jagged edge helps scramble any diffraction effects (airy rings, etc) that would normally come from a good clean aperture.

You can also always just couple your projector into a piece of fiber and then have a prefect* overlap between your colors and perfectly round beam. *only limited by the quality of the lens you use for collimation and variation of the mode field size for different wavelengths, both of which should be pretty negligible. The beam parameter product for a 62um telecom fiber is really not that bad when you compare to the starting beam quality of a knife-edged projector. Plus you get a free fiber remote launch for your projector

[kecked]

If someone can make the damn filter as a module it would be really hot I bet.