Choosing a violet laser

[lasercraft]

I want to buy a violet laser pointer, and I'm hoping someone can recommend one to buy. This is for an art project which I call a "Laser Frame." Right now, it's essentially complete, and is hanging on my wall, and has a green laser pointer in it. See the attached image.

What I'd like to do is replace that green laser pointer with a violet laser pointer, to make it match better with the décor of the room.

The one in the frame right now is a green laser pointer I bought at Radio Shack:

Green Laser Pointer : Laser Pointers | RadioShack.com

I'm not sure what the power of that laser pointer is; the tech specs are vague and only say "<5 mW." Whatever its power is, I'm pretty sure I would need a violet pointer of even higher power, because the eye is less sensitive to violet light.

If you'd like more details about the project, ask and I'll provide them.

 

[Speedy78]

I really like this. What size pointer are you currently working with? If its a pen style you may need to stick with the same. Ebay has alot of these and you can find them in 405.

 

[lasercraft]

Thanks, I'm glad you like the project. Yes, the pointer is a pen-style pointer. It fits into a compartment at the bottom of the frame. I'm attaching another photo, with the top and bottom panels removed, to show you what I mean. It's 1/2" diameter and about 6.5" long.

So, yes, another pen-style pointer of the same shape and size would be great. I'll look on eBay as you suggested. But, I might be able to use a larger pointer, and cut the wood to fit the new pointer. Is there any advantage to buying a pointer that's not pen-style? Like, lower price per milliwatt? Also, it might be nice to have a pointer than can be plugged into a wall outlet, so that I don't have to keep changing batteries.

 

[Shakenawake]

how long will you need the laser to be on at a time? the higher the power, the less this time will be in general. good heatsinks help, but I'm not sure what the max power that can be left on would be

 

[Speedy78]

Keep in mind the violet is less visible than green. For plugging it in all you will need to do is find a DC wall wart that's outputting the correct voltage for your laser.

 

[zyxwv99]

According to my calculations you need a 1 watt 405nm violet to equal a 532nm green. Or actually 925mW. That's according to CIE 1978, which is much more accurate than CIE 1931 for wavelengths below 460nm. (According to CIE you would need 6.7W, which is noto right.)

Here's a link (the data tables are near the bottom): http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/Sample-Chapter.pdf

Also, 5mW 532s tend to be overspec by a factor of 2 or 3, which could throw everything off. Maybe what you need is a dollar-store 532, then any wavelengths except 405.

 

[lasercraft]

Can I get some further advice about DC adaptors (wall warts) and heat sinks? With the current laser, the green one, I've tried connecting it to a DC adaptor. It works, but it seems to automatically shut itself off after a while. Is this because it's overheating? If so, how would I go about using a heat sink with it?

Also, I knew I'd need a higher power for violet, but I didn't realize it'd have to be as high as 1 watt. First of all, that's probably going to be expensive. And second of all, isn't 1 watt powerful enough to burn the wood? I might just keep the green one.

 

[Speedy78]

Yes it will burn the wood for sure. You csn always go witha low powered 450nm laser. Would be blue instead of violet. Your dc wall adapter is most likely supply to much voltage to the driver for it to overheat like that. Look on the sticker and see what the output is. Your laser will be 1.5V if its one battery or 3V if its two.

 

[Leodahsan]

@OP
I really like your idea! :yh:
Bigger, rectangular mirrors could make a "laser lightshow frame"...

Maybe painting some flurescein (+ some transparent resin or paint) inside the glass would make a things a lot cooler?
Ideas...

 

[lasercraft]

Speedy: When I used the laser with a DC adaptor, I matched up the voltage. The laser uses two AAA batteries, so it's 3 volts, and I'm using a 3 volt DC adaptor.

Leodashan: Thanks, I'm glad you like it. Maybe at some point I'll put bigger mirrors in it, or more mirrors.

I guess I'm getting off-topic here. This forum is for blu-ray and violet lasers, but now I'm abandoning the idea of using a violet laser, and I'm talking about adaptors and heat sinks. Maybe I should start a new thread in another forum on this site.