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ArcticMyst Security by Avery

would one of these be good in a projector?






andy_con

andy_con

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Benm said:
I got this information from the CIE tables for the luminosity function. The values i stated are for equally bright looking beams/dots of each wavelength. The values required for exact white appearance are slightly different depending on the exact wavelengths used, but very close (within a few percent).

This doesnt mean that you cannot make a full color projection using equal amounts of 445, 532 and 635 though. Provided many combinations are present in the show, the full mix woul still appear (most) white to an observer. The projection as a whole would appear very green though when viewed side by side with oher light source.
Click to expand...

well the info is poo, come/go to a laser meet and see the perfect whites made by 1;1;1 projectors using 532 445 and 640
 
andy_con

andy_con

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i couldnt give to shits what a computer program says, see these colours and powers in real life then comment and ive seen and have plenty
 
andy_con

andy_con

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what modules?

ill make you a red module if you want power from 200mw to 5watt @ 660nm
 
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Gappa

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how would it be done? by using a single diode or combining several?
 
andy_con

andy_con

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depends on the power you wanted.

but generally combining more than one diode
 
Morgan

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^... Andy's combo units are a sight to behold! I speak from personal experience here too... :D

M
:)
 
Cyparagon

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I'd like to point out there's a difference between equally bright dots, equally bright beams, and white balance. 445 is closer to the peak sensitivity of the "blue" cones so you need less to make white. Something like that, anyway.

Of course, a 300mW 445 will look dimmer than 300mW 473, but 300mW of 445 will have more of an effect at adding blue to the white. Hope that makes sense :undecided:
 
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Gappa

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yes the further in the color spectrum the more balancing effect that wavelength can provide. so 660 would have have more "red" than 635 but you need more wattage because of the makeup of our eyes?
 
andy_con

andy_con

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Gappa said:
yes the further in the color spectrum the more balancing effect that wavelength can provide. so 660 would have have more "red" than 635 but you need more wattage because of the makeup of our eyes?
Click to expand...

well a 635nm module will produce a beam of 5mm by 8mm so alot will be lost off the galvo mirrors
my 660nm build will have a beam of 3mm by 3mm so none will be lost off the galvo mirrors

i have known people to loose 40% of the power when use a 635 module due to so much missing the galvo mirrors

a tight beam looks brighter than a fat beam, but in general yes you will need more 660 to get a good colour match.
 
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ElektroFreak

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Unless of course you use DT-20H galvos, which have larger mirrors but maintain 20kpps speeds. They don't cost significantly more than the other DT options, but I haven't seen too many people using them. It seems to me that they would be an ideal choice and the simplest solution for beam projectors using wide beams.
 
andy_con

andy_con

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ElektroFreak said:
Unless of course you use DT-20H galvos, which have larger mirrors but maintain 20kpps speeds. They don't cost significantly more than the other DT options, but I haven't seen too many people using them. It seems to me that they would be an ideal choice and the simplest solution for beam projectors using wide beams.
Click to expand...

but then you would be left with a tiny green beam and a big fat red beam which isnt great for colour mixing
 
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ElektroFreak

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True, you'll still get the red fringes.. I don't mind that so much myself since it's hard to notice from a distance or when the beams are overhead, but I could see how it would be important to minimize that issue when audience scanning.
 
andy_con

andy_con

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i think in this day and age its more about beam quality than power.

heres my results using red, as you can see red beam is same as green at distance making for perfect mixing

20100919_001-1.jpg
 
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