Pushing Argon tube to the limit

[steve-o]

Yea i was looking for something close to 488 (my favorite laser color-I've always been partial to turquoise/ blue/green colors ) -everybody's got their fav's I guess..
I wonder if I could mix 473 with a small amount of 532 using some kind of combiner..?

[buffo]

Of course you can! And if you have analog modulation on both lasers you can create any color inbetween the two. (If you only have TTL modulation you can still create a cool looking "teal", but it will be a fixed color based on how much blue and green power you have.)

A simple "reflect blue, pass everything else" dichro is what you want. See if you can get the blue cutoff frequency to be around 500 nm or so. (longer than 500 nm passes, shorter than 500 reflects)

On the other hand, if you get a trichro, you can use just the green and blue windows to accomplish the same feat.

Adam

[steve-o]

Yeah I've got an Edmunds teal dichro at the house, I just need the blue laser. Ive got the argon but it's too low power-I'd like to simulate the argon color with DPSS lasers. How much blue power would I need do you reckon to mix with the 200mW 532 green I've got now to get the appropriate color mix? Probably VERY expensive and out of my present budget range :cry: Unless I attenuate the green ALOT.. but then it'd be low power again..

[steve-o]

Looking at his cool applet:
http://www.cs.rit.edu/~ncs/color/a_chroma.html
(was on another thread in PL)
I would need about 65% blue 473 and 35% green. Does that sound about right?

[buffo]

Yeah, that's about right. I was going to say that if you want to mix the blue with 200 mw of green and keep the color balance perfect, you're going to need a shitload of blue!

But seriously, the ratio is about 2 to 1 for blue to green. (Closer to 5 to 1 for red to green) So if you've got 200 mw of green, you'd want around 400 mw of blue. And at 473 nm, you're talking about spending a small fortune. (Well, it would be a lot of money for me anyway!)

However, after viewing the output of several projectors that have really bad color balance (at least as far as the numbers go), I've learned that the numbers don't tell the whole story. That is, even if your numbers are way off, you can still create beautiful colors and be very pleased with the results.

Do a search for color balance here on PhotoLexicon and you should find a few threads where this is discussed in detail.

On the other hand, if you're available on the 27th of January, haul yourself down to Orlando Florida (I know, it's a hell of a long way away...) and you'll get a chance to see a few projectors in operation - up close and personal like. I know that one of those units will be running a full watt of green with just 200 mw of blue and 500 mw of red. Another will have 125 mw of blue with 100 mw of green and 200 mw of red. And depending on what some of the other attendees bring, it's quite likely that you'll be able to view at least one projector (if not more than one) that has close to the ideal color balance of 5-1-2, R-G-B. So you'll be able to see the effects of color balance on the output.

Adam

[steve-o]

That'd be way out of my budget! I think I'll go for the orange laser. That's my next favorite color. A 200mW red Maxyxmodule and a hightly attenuated green using a beamsplitter or dichroic or something...
Orlando FLEM is 9 days away. I'll try to make it if i can... thanks for the invite..