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FrozenGate by Avery

635nm vs 650nm






What would be really great to find is a 635 with both decent power (maybe a 100mw or so) AND good divergence or focusing ability! I had originally ordered a portable 635 pointer from the first CNI GB, and while it was defective with regards to power output when Glenn (Scopeguy) received it, still, he said that the divergence was pretty lousy - the dot was something like 2 or 3 cm wide at about 10 feet!
So, keep in mind that a commercially available 635 probably won't have a very small beam. But if you only want to use it to burn then it won't matter, but I had wanted one for a nice, sharp, bright red visible beam.
 
New diodes have hit the market. They're 642nm and have a beam just as good as their 660nm counterparts. They run only $99 for 150mW in the PL group buy.
 
I saw those.. 642nm would actually be in spec for a 635 +-10 diode so I'm sure the visibility is nice. I might get in on that. My problem is there are always too many decent deals around and not enough cash..
 
HIMNL9 said:
Also if is true that, basically, the peak sensitivity of the human eye is on the green region, perhaps that not all the peoples have the same identical sensibility curve about level and spectral range, also in absence of color blindness (daltonics) ..... so, how can we say this is better than that, or brighter, if anyone can see it differently ? .....
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It's actually true that for people with 'normal' trichromatic vision, small differences between the photoreceptors exist troughout the population. This is normally not noticeable, but it might present at edges of the spectrum.

The again, these differences are quite small (unless pathological in the sense of missing or malformed receptors), and mostly affect the M cones (most sensitive to green) anyway.

Interestingly, you can have a mutation that developed in early foetal stage causing a difference it color perception between your eyes.
 
Andycon pointed out some 250mW 635 diodes here for a mere $100. These of course have the standard horsesh:)t beam.
 
I don't know of any 635nm diodes at those powers that don't have multimode beams.. I have a 300mW multimode red in my RGB and it does fairly well. If you're not a laser expert, you'd never know the difference since it's mixed with other colors most of the time.. Of course that assumes that the laser would be used in a scanner.
 
Cyparagon said:
According to my source, it is three times brighter than 660 (also a common red diode wavelength) and 2.3 times as bright as 655. 532 is 4.7 times as bright as 635. This is not for color mixing, just apparent brightness under photopic conditions.
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How do you measure this ?
The only way measuring laser (visible light output) power I think is measuring it pointing it to a white surface on a defined distance from both the laser to the surface and the surface to the luxmeter.
 
You can't measure this with a luxmeter, as this device already incorporates the curve (it takes the sensitivity of the eye into account, unlike a power meter). This curve, the spectral sensitivity of the human eye, can only be determined by testing with a large number of people and averaging the results. I guess this is done by giving them two narrow-band light sources and then asking them to turn the intensity of one up or down until it appears equal in brightness to the other one - then the relative power of both is the inverse of the relative sensitivity for this wavelength pair.

@themandalorian: yes, it should be clearly brighter (according to cyparagon's source, 250mW of 635nm should be about equal to 50mW green).
 
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partylighter said:
How do you measure this ?
The only way measuring laser (visible light output) power I think is measuring it pointing it to a white surface on a defined distance from both the laser to the surface and the surface to the luxmeter.
Click to expand...

YOU (or I) don't measure it, the EXPERTS measure it. A $30 piece of equipment from DX doesn't cut the mustard.
 
for a rough idea of how it compares to 660nm, click the link in my sig. Granted though, the 635 was 3mw and the 660 was 4mw, but it should still give you an idea.
 
@ themadelorian

hey are you getting a 9mm 1W red in a kryton beast from Darkarmyofone?
 
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