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ArcticMyst Security by Avery

685nm 35mW Laser Diodes on Ebay!

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How come when Comparing 635nm to 650nm witch is around the same difference between the 650nm/660nm to 685nm that the 635nm looks a different color too.?

How come when comparing a ~25nm Difference from other wavelengths you can see a difference.

Because it is on the edge. I could follow that logic in 25nm increments all the way to radio waves, but saying "radio waves are just a really really really deep red" doesn't make any sense. Just the same, Gamma rays aren't a really really really deep violet either. You'll also notice there is only a slight difference between 635 and 660. Unless you're really looking for it and/or unless you have them side-by-side, you won't notice a difference.

Try turning down the power of your 660 pointer. You'll get them to look very similar. :)
 
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Because it is on the edge. I could follow that logic in 25nm increments all the way to radio waves, but saying "radio waves are just a really really really deep red" doesn't make any sense. Just the same, Gamma rays aren't a really really really deep violet either. You'll also notice there is only a slight difference between 635 and 660. Unless you're really looking for it and/or unless you have them side-by-side, you won't notice a difference.

OK I think understand now.

So because its on the edge its Just dimming out to IR Rather then Becoming deeper in color. Witch is why its giving the illusion of it being a deep red.?

Edit: Dint see the last part.

In Post 58 i have a 1-2mW 650nm comparing to the 13mW 685nm.:) I think i have to get it alot more Lower then that.:)
 
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Mine arrived, but unfortunately they had been stepped on, the leads completely crushed and one window cracked... Disappointed in that, looks like the thin envelope they were in had been stomped on or driven over.

To those who have gotten these working - is it definitely deeper red, to you, than 650?
DANG buddy! you have the worst luck with damaged deliveries!!

MIne came in today in pristeen condition. I had to make the trip to the PO and sign too.
 

DJNY

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Read about them some time ago..

Anyone interested in building me one, is welcome to send me an offer via PM :beer:
 
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So i was really tempted to extract another diode today to test and see what the output was since the first one i extracted and installed in an AixiZ module was only doing 13mW at 48mA.

So i did Just that.:D

This one is Great:


Iam using an Aixiz Glass lens running at the same 48mA.

Now you can see the beam better with some fog in the Air.

I am now very Happy.:wave: I cant wait to get my Hosts in to put these 3 diodes in there homes.:evil:
 
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Just put mine together.

At 66mA, I'm getting 45mW. And that's with aixiz plastic. I do admit the WL is a bit of a trick, as my 40mW 638 sure does look a lot brighter :) But also, it is a very red red. To cameras they look pretty similar..

Now if I only had room to add something else to my sig...
 
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Nice.:) You are Running it Higher then Normal. :) Let us know how that works out.:) Iam going to Run 3 different ones in there 35mA 50mA & 60mA. range.

I really like how my 32mW 685nm Looks next to my 650nm.

Red is one of my favorite colors.


Edit:

By the way your Sig is one of my Favorites to look at.:p
 
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OK I think understand now.

So because its on the edge its Just dimming out to IR Rather then Becoming deeper in color. Witch is why its giving the illusion of it being a deep red.?

Edit: Dint see the last part.

In Post 58 i have a 1-2mW 650nm comparing to the 13mW 685nm.:) I think i have to get it alot more Lower then that.:)


We don't have photo-receptors that can "see" every wavelength.
The color we perceive depends on which cones are stimulated (red, green, and blue). Wavelengths that are on the edge of our sensitivity will stimulate few photo-receptors so they appear dimmer.

For example:
473nm stimulates some "blue" and some "green" cones. As the wavelength gets shorter, you start activating more blue cones than green cones. If you move closer to 532nm, the light will stimulate more green cones than blue cones.
The reason there is little difference between ~700nm and ~800nm or 660nm and 685nm is because there are no "infrared" or "deep red" cones to stimulate, so the only photo-receptors that are being activated are the same ones used to perceive red - and few of them.

Does this make any sense?
 
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We don't have photo-receptors that can "see" every wavelength.
The color we perceive depends on which cones are stimulated (red, green, and blue). Wavelengths that are on the edge of our sensitivity will stimulate few photo-receptors so they appear dimmer.

For example:
473nm stimulates some "blue" and some "green" cones. As the wavelength gets shorter, you start activating more blue cones than green cones. If you move closer to 532nm, the light will stimulate more green cones than blue cones.
The reason there is little difference between ~700nm and ~800nm or 660nm and 685nm is because there are no "infrared" or "deep red" cones to stimulate, so the only photo-receptors that are being activated are the same ones used to perceive red - and few of them.
Does this make any sense?

Yes it makes perfect sense Now to me. The Part is Red is the Part i dint understand but Now i truly understand exactly what is going on.:bowdown:

Sometimes it just get me so confused to understand certain things and the way it works. This was one of them.

Learn something new everyday on LPF. No matter how much you know there is always something to learn.

Thanks RA_pierce , Cyparagon & aryntha for the help.:beer:
 
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rhd

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It always amazes me that there are colors we cannot see, yet I cannot imagine what they would look like ;)
 

mfo

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We don't have photo-receptors that can "see" every wavelength.
The color we perceive depends on which cones are stimulated (red, green, and blue). Wavelengths that are on the edge of our sensitivity will stimulate few photo-receptors so they appear dimmer.

For example:
473nm stimulates some "blue" and some "green" cones. As the wavelength gets shorter, you start activating more blue cones than green cones. If you move closer to 532nm, the light will stimulate more green cones than blue cones.
The reason there is little difference between ~700nm and ~800nm or 660nm and 685nm is because there are no "infrared" or "deep red" cones to stimulate, so the only photo-receptors that are being activated are the same ones used to perceive red - and few of them.

Does this make any sense?

it makes perfect sense, but as I asked earlier howcome there's such s huge difference between 445 and 405?
 
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it makes perfect sense, but as I asked earlier howcome there's such s huge difference between 445 and 405?

Don't quote me on this, but I believe it is because the blue side of the spectrum also stimulates red and green cones.
Humans have fewer blue cones than red and green cones, so the blue cones are much more sensitive in comparison. Also, the blue cones are present around the red and green cones which is part of the reason there is noticeable chromatic aberration with violet-blue light.

Since the perception of color depends on the ratio of the red, green, and blue cones that are stimulated, and blue wavelengths also stimulate red and green cones in addition to blue cones, we can perceive 405nm as a different color than 445nm because the shorter wavelength is stimulating more red (and some green) cones in addition to a few blue cones.

People that lack red sensing cones (some types of color blindness) can often not distinguish the difference between cyan, blue, and violet.
So to them, 473nm, 445nm, and 405nm may appear to be the same color. Apparently, humans also use the red "channel" to perceive violet and blue light.
 
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Johnyz

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Got them today, but apparently my camera is blind at that wavelength, I'm barely seeing any light with it... anyone having the same issue? I'm driving it at about 50mA with a temporary LM317 DDL driver with 9V battery I was using for the red diode in PHR.
 
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The Brightness of the dot at 50mA witch should be ~30mW - 35mW will be close to 1-2mW of 650nm .

Do you have a LPM.?

Also you could have gotten a low efficiency one like i did that only put out 13mW at 48mA or a Zombie.

Edit:

Also the only way you can see the beam is by using some Fog or Smoke. :)
 
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