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FrozenGate by Avery

Blue=violet+green?

K

kingbowser

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Hi, I need to build a RGB laser system, and I was thinking: "If I merge violet and a little bit of green, can I obtain a good blue?" Have you the proportions of V and G in order to have a good-looking blue (a color similar to the 475nm wavelength), or a way to calculate it?
Thanks, Riccardo
 





wouldnt violet and green make more of a pink or magenta? not sure...
 
It depends on proportions, with the right amount of green over the violet you'll obtain blue (or any other color between them) :)
 
FireMyLaser said:
The answer is no. You can't mix any colours to make blue, green or red.
Click to expand...

"No, noh, noh, noh,no,(pause) yes!" To quote one of my favorite Britt TV characters.
In a way, your both right, as well as classical color theory and real world go..

Go over to Photonlexicon. sign up, learn where the top sekret FTP site is, or contact Tocket via PM, download Tocket's Chroma program, and you'll find there is a non linear bug in the eye's response curve for bluing small amounts of green with deep violet... Chroma is made for predicting white graphics color temperature by inputting wavelength and power , but it does considerably more then that, including calculating theoretical wavelengths from binary and trinary combinations, based on the IEC curves.. At least in theory, I have not used the new somewhat standalone version.

Then do some public service and arrange for Tocket to be able host it over here so the sekret FTP site does not get swamped, the powers that be can barely manage and protect it as it is..

Steve
 
You can make a blue colour, but, after they are combined you now have a two wavelength beam. If you are to try and use dichros or any other optics other than a mirror, the beams will seperate and react to the different coatings. What will reflect 405nm will pass the green and so forth.

In the pic I posted is a combined beam labby that puts out a similar colour to that seen on a white piece of paper with 405nm. Its a nice blue, but again, if you pass through optics or AR coated , there will be undesired results. If you make a blue colour and run it straight to a mirror in a scanner etc, it will work.

In the pic, the beam is passing through a prism. You can see that the beam going in has a defined center which is the green. As it leaves the prism, the two seperate.

My camera is really sensative to the 405nm, so its hard to see the blue colour...

kingbowser said:
Hi, I need to build a RGB laser system, and I was thinking: "If I merge violet and a little bit of green, can I obtain a good blue?" Have you the proportions of V and G in order to have a good-looking blue (a color similar to the 475nm wavelength), or a way to calculate it?
Thanks, Riccardo
Click to expand...
 

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I can say for sure, there is NO hint of blue what-so-ever in a G+V set-up. It will make an excellent blueish-green and turquoise. But it never gets close to blue. It morphs from turquoise to violet, and that's it. The shades in between are very interesting, I can't even explain the colours I'm seeing, but it AIN'T blue.
 
FireMyLaser said:
I can say for sure, there is NO hint of blue what-so-ever in a G+V set-up. It will make an excellent blueish-green and turquoise. But it never gets close to blue. It morphs from turquoise to violet, and that's it. The shades in between are very interesting, I can't even explain the colours I'm seeing, but it AIN'T blue.
Click to expand...

We should also tell you there are a couple of minor genetic variations in human eyes.

My boss asked me to find a way to get the krypton ion 752 nm Line going. I'm aligning the mirrors on the laser looking for the usual flash. I'm doing a vert search, which means I've disconnected some fragile stuff and have stuck a screwdriver in the mirror plates, and am, as lasers go, rather violently swinging the mirrors around the vertical looking for the cavity to line up while turning a 100 tpi micrometer on the other axis. I've been doing it for a hour, and it usually takes me less then 5 minutes to align a cavity. A Russian postdoc walks into the lab and says, "Steve Cannot you see that bright red flash???? " When I got it going 250 mW of that looked like 1 mW of 670 to me...
Yet Alex could see well into the IR, but he did not do well in the greens and blues.....

So many people see part of what your seeing as a mild blue... I'm one of them.

We wont even get into colorblindness.

Steve
 
I cant agree with this, but it may be my eyes that are outta wack here...

If I shine a 405nm at a piece of plain white paper, the dot appears to me as blue. Now if you aim that same 405nm at the wall, it returns to its purple violet colour.

With the labby that I made, the dot looks just like the 405nm on white paper, but the combined beam will produce this same colour on almost any surface, and when lit by smoke in the air.

There is also another element to this. When I made my labby, I selected a diode (PHR) that was the most visible out of a bunch tested. I have PHR diodes that are a really deep purple, and others that seem more blue. Though I dont have any real method of testing wavelengths, I just go by eye and the brightest of the bunch to mix with green.

Mind you, ive always reffered to the combined beam as 'ice blue', im still seeing blue(ish).

I was testing some old lasers of the shelf and a decent comparison can be seen in this pic. Remember, my cam really pics up the 405nm but the blue(ish) colour can be seen coming from the black labby in the top right.

So what colour would 405nm lighting up a white piece of paper be?



FireMyLaser said:
I can say for sure, there is NO hint of blue what-so-ever in a G+V set-up. It will make an excellent blueish-green and turquoise. But it never gets close to blue. It morphs from turquoise to violet, and that's it. The shades in between are very interesting, I can't even explain the colours I'm seeing, but it AIN'T blue.
Click to expand...
 

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LOL

interesting answers :)

in the thread My RGV is Alive! I can see in the photos a good-looking blue. This is the effect I am looking for. Have you the proportions of violet and green in order to achieve that color?
P2200155-r3.jpg


Thanks
 
Why not combine your beams first, then ramp the current slowly up for the green? Your 405nm and 532nm will not be exaclty the same as others have, loss from optics etc.

With this in mind, by adjusting the current to your green, you can just pick the one you want...
 
Your seeing the blue "whitener" organic dye in the paper and white clothes flourescing blue. The dye is there to convert solar UV to blue to make you think your clothes or the paper is whiter... Aim it at a piece of granite or a white painted wall (TiO2 based white paint doesn't glow) maybe a white coffee cup, and you'll see your eye's real response.

Steve
 
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