Is tight beam possible out of 445nm/450nm MM laser?

[w8r]

Hi everyone. This is probably where the highest density of experts gather so I'm open to hear your experience and suggestions.

From these powerful, multimode laser diodes, is it possible to have a ~2mm beam in the near field with a small divergence (2mrad to 5mrad max)? I'm sure it depends on what laser used, etc... but I'm trying to gauge from your expertise what is possible.

If this has been discussed before please guide me to the thread.

Thanks for you help on this.

Walter

[VDX]

... with double-prisms-beamshaping its much better, than with the collimator optics alone ... but don't expect wonders

Viktor

[sbk]

Hi Walter,

That should not be a problem, since the usual specs we can expect from such diodes with good optics is around 4-5mm with <1mrad, sometimes up to 0.5mrad.

So either put a 3:1 telescope / beam expander in front of a standard diode assembly, either use a different kind of collimators to reach the target result. You will get 1.5-2mm with 1.5-3mrad.

Depends also if you need a perfect square beam, or if a rectangle beam will also fit your needs, but usually cylinder lens correction is working quite great.

Sebastien

[w8r]

Viktor and Sebastien, thanks for your advice. This is a great starting place and I'll look in to these optics and see what can be done.

[sbk]

U're welcome.

Btw, I had a good experience with OPT Lasers (Poland, not China) for their mounts and optics, you may have a look : https://optlasers.com/cylindrical-lenses/

You may also ask some of the laser manufacturers out there, like Phritzler (Live-Lasersystems) or Edison (Brightlight lasers), they have far more experience into optics and they could even build a custom solution for you :-)

[mixedgas]

John Laughlin at Technological Artisans can order you a Goldenstar 445 module with integral optics inside the diode can to correct the beam shaping. I have the corrected, circularized, blues inside my 5 watt projector and I know they will come close to your specifications. In my case the beam is is a rounded, symmetrical, square in the near field, and if I were to bother to spatial filter it, it would be beautiful and reasonably circularized.

It is a beam shaping lens implanted on the diode mount, then the diode is gas filled and re-canned, not something you can do at home.

Steve

[w8r]

U're welcome.

Btw, I had a good experience with OPT Lasers (Poland, not China) for their mounts and optics, you may have a look : https://optlasers.com/cylindrical-lenses/

You may also ask some of the laser manufacturers out there, like Phritzler (Live-Lasersystems) or Edison (Brightlight lasers), they have far more experience into optics and they could even build a custom solution for you :-)

I've seen the OPTLASER designs and look good. I'll talk with them. I'll also look at the other two. Thanks!

[w8r]

John Laughlin at Technological Artisans can order you a Goldenstar 445 module with integral optics inside the diode can to correct the beam shaping. I have the corrected, circularized, blues inside my 5 watt projector and I know they will come close to your specifications. In my case the beam is is a rounded, symmetrical, square in the near field, and if I were to bother to spatial filter it, it would be beautiful and reasonably circularized.

It is a beam shaping lens implanted on the diode mount, then the diode is gas filled and re-canned, not something you can do at home.

Steve

Steve, this is quite interesting. I'll reach out to John. I'm willing to test a few things to get a good beam, hopefully at high efficiency.

Thanks!