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Misterwilling dooooo it, I'm getting one 
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ArcticMyst Security by Avery
635nm vs 650nm
- Thread starter zxn474l
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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.
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.
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Hmmm the one I'm getting is focusable, think that will be a problem?
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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.
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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..
Benm
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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.
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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.
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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.
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Do you guys think a 1 watt 635nm will be brighter than a 50mw green?
dr-ebert
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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).
@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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Thanks! That makes me even more excited I had no idea the beam would be so visible
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YOU (or I) don't measure it, the EXPERTS measure it. A $30 piece of equipment from DX doesn't cut the mustard.
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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.
