Topic: First Post - Blu Ray lasers in RGV scanners

[Fanny Pack]

I'm interested in hearing from those who have experimented with the blu-ray diodes for ue in RGV scanners.  With the blu-ray diodes now being relatively affordable and with different power levels I am thinking of using one in a scanner.  Actually, I am thinking of combining two PHR diodes. 

So, what I am wondering is if you have about 150mw of blu-ray, what levels of green and red would go with that to make a decent spectrum of colors?  I assume it can't be much but how much?  Has anyone tried it?  With a little fog, is a 150mw blu-ray beam visible enough for baem shows?  etc etc etc.

DrLava, your flex drives work OK for blu-ray diodes?  I'd like to have a dual driver PC board to save space and for ease of mounting.  Any chance of doing that in the future?  That norm guy has a triple driver board but I don't like his boards since they use shunting for switching power on and off so they get hot and need big heat sinks.

[BlinkenLights]

i will let you know soon.. im building the RGV with 2 phr and 2 open can

Flex == Bluray YES

im having 400ish or so red, 150 green and 150ish bluray

[Fanny Pack]

Interesting combo.  make sure to put the blu-ray closest to the galvos.  You use a lot going through dichros.  Reflecting off of them doesn't drop much.

[BlinkenLights]

thats how i have it setup...
but thanks fer the advice

[James]

One-of-these-days ...

That's what I'm trying to get together as well!

Some day, I should get my red diode pair back in working order. It's being built (re-built) for me by sk8.

I have a DPSS green and an AOM that Steve Roberts gave to me. I still haven't set it up and tested it yet!

I'm too busy working on LaserBoy code and DAC construction.  :

I already have a single BluRay diode that sk8 made for me, with a drlava flexmod driver. It's lots of fun! It is putting out about 72mW.

James. 

[Fanny Pack]

You're going to use an AOM instead of diode modulation?

[James]

Absolutely! 

It's WAY faster and very linear.

I have a PCAOM on my gas rig.

I'm spoiled that way.  :

James. 

[Fanny Pack]

That's cool.  Is there much power loss with those things?  I don't much about them.

[James]

Well... if it's set up right, you lose about 20%. But for a DPSS green, who cares? They are easy to get in power outputs that blow away red or violet anyway.

The problem with DPSS is that modulating the IR pump diode does not take into account that the frequency multiplier crystal takes time to work and is also very temperature sensitive. The best thing to do is just turn it on and let it warm up and be stable. Then modulate the beam with an AOM.

I plan to directly modulate the diode for the red and the violet.

James. 

[Fanny Pack]

Not a bad idea but unless your green just doesn't have analog modulation you might want to check to see if it is really an issue.  My cheap TEC-less green module was TTL controlled and I added a die4drive to it to go to analog and it is wonderful.  Couldn't ask for anything better.  On the other hand, my expensive blue laser is pretty crappy when it comes to modulation.  Which brings me back to why I am very interested in the blu-ray diodes.  My homemade red works fantastic, too, but the beam is a bit fat at the exit of the module.  Seems to be typical with the red diodes, though.

[Lazerjock]

I'm building a RGV projector too. I am using Dr.Lava's Flex to drive both the red and BR. I was hoping to have it finished to show off at bastment LEM 2009, but I'm just too busy.
I need to repair my scan amp too.

My BR is putting out 100mw
My red is putting out 125mw
My green is 300mw adjustable. (I will need to turn it down)

Yes the red is fat at the output, just make sure your mirrors are big enough to catch the whole beam. At a distance it ends up roughly the same diameter as the green.

The BR is another story. No matter how tight you collimate it, it appears larger than the others. This is due to the eye's in-abailty to focus well at that wave length. The effect is a violet halo around the other colors.

My solution to the halo effect is to use a screen that floresces under the BR laser. (a cotton sheet works well) This changes the color from vilot to a true blue and seems to make it brighter. It's all just an illusion, but it gives a great color mix and eliminates the halo.

[Absolom]

James, is it better to get a PCAOM or just get AOMs for each laser?  PCAOMs are $$$ aren't they?  I think the AOMs for a specific wavelength range are a little cheaper or am I wrong here?

[Absolom]

Let me rephrase my question.  Do they have AOMs that are broadband covering from 400nm to 700nm?  Not polychromatic though.  That way, you could put one inline with each laser.  I would imagine this would be way cheaper.  I know very little about them myself.

[BlinkenLights]

wish mark posted here.. he could probably answer that

[ImageLight]

wish mark posted here.. he could probably answer that

Your wish just came true..

I believe that AOM's will modulate just about any wavelength as long as the crystal is not AR coated for any specific laser line. They just have to be tuned
to the appropriate polorization and Bragg angle.

Mark