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How visible do you see 405nm ?

Alex2893

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I have always wondered how visible other people see 405nm. I seam to be able to see it very very well because I can see the beam of a 45mw 405nm laser and with night adaped eyes I can see a 100mw 405nm laser beam very well even from the side. To my eyes a 100mw 405nm laser has a more visible beam compared to a 220mw 650 nm but the dot on the 650nm laser is brigher. I use to have a 1w 405nm laser and the beam was super visible outside at night. But some people can't see 405nm that well. Some can't see the beam very well even at powers over 1w from the side.
 
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Richie89

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Re: How visable do you see 405nm ?

On My 800mw 16X 405nm I can see the beam very well at night. Violet looks pretty bright to me also. Funny thing is that everyone of my friends including my girlfriend say that my purple lasers really hurt their eyes but it doesn’t hurt mine at all.
 
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RA_pierce

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Re: How visable do you see 405nm ?

405nm is very dim to me.
I also noticed that the beam of short-wavelength lasers appear brighter, compared to a red laser. The "dot" of the red lasers can be brighter, though. I'd speculate that this is due to increased scattering of short wavelengths by particles in the air. Any other ideas?

When I really liked PHR-803T diodes, I built a lot of lasers with them. I noticed that there were some that appeared much brighter at the same current. I think these were longer wavelength diodes. The difference may have been enough to result in an increase in brightness but not enough to perceive it as a different color. Variance in efficiency is probably too little to perceptibly affect variation in brightness.
It may be fun to find some long-wavelength PHRs again since they are so cheap.

my purple lasers really hurt their eyes but it doesn’t hurt mine at all.
It means all your cones are already burnt to a crisp, so no more damage can be done. RIP.

By the way, it's spelled "visible"
 
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I can see the beam from my wimpy ebay 405 in the dark, I can seen the beam from my 800mW 405 in a well lit room. I guess I can see 405 reasonably well.
 
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well i can see a beam with less than 5 mw 405nm pointer in a dark room,actually i have to agree that i see better the beam on 405nm than 650nm but this has to do with the dot brightness,i see the dot of the 650nm brigher thats why i can't see the beam well but if i aim it to a dark surface that changes and the beamshot becomes brigher.

405nm is my favorite color for playing with night adopted eyes ;)
 
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Merpie101

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i see 405nm about as bright as typical 650nm. much brighter than most other people see it i guess but im happy with it. i have a cheap 303 thats probably running 50mw and the beam is visible from the side in a mostly dark room im really exited to get enough money to get myself 800mw of this stuff or maybe one of those sanwu 1.6w 405s
 

paul1598419

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Got to be a MM diode. I don't see them PBS combining two single mode diodes.
 

Alaskan

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I wasn’t aware if a MM 405, I’d sure like to find the manufacture info on it, or at least a part number.
 

CurtisOliver

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Shorter wavelengths scatter more in the air so the beams appear more visible. Rayleigh scattering is the cause. I personally find 405nm bright, but not visibly in a direct sense. It strains my eyes like a powerful blue etc but the overall purple glow isn’t that bright to me. Most of the brightness comes from the materials it’s fluorescing.
I also find it difficult to focus my eye onto.
 
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Radim

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I see it very well and quite bright - dot and beam (yes, when standing behind the laser - the "most difficult to see" angle). Definitely it is not comfortable to look at dot of my 500 mW laser from close distance. Further even weak beams of higher maxima after the beam has passed diffraction grating are visible very well (even when I'm behind the laser). In adition I observe many effects like further dots around the central dot on certain surfaces hit, fluorescence, etc. However in far field the dot is harder to see, especially on some dark and matt surfaces.

Edit:

See this:




Source: Wiki - linked under click on the pics

Some easy reading related to the topic:
Let the light shine in
You don't have to come from another planet to see ultraviolet light, says David Hambling


Note: Human eye is capable to see beyond obligatory 400 nm - 700 nm, it varies from individual to individual (the distribution above is some kind of statistical average). I can see even some IR for example (yes I noticed the glow when using IR remotes), for lower end it might be even around 380 nm. Just in case of "tail" wavelengths the intensity decreases, here the rods are more effective, but they cannot distinguish colors - therefore "extra deep red" (IR) might be perceived as gray.


Source: Wiki - see under click on the pic

Here on the pic above you can see rods in deeper layer of retina (on the right).

Keep on mind human eye is a very complex organ, just a brief look on its structure is amazing and making those curious to explore more of its function and further mechanisms of vision:

Source: Wiki - reading and description is linked to the pic


Further related:

Richer color experience in observers with multiple photopigment opsin genes (more advanced reading)
 
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Oddly I've yet to experience any eyestrain from using my 405 and 445 lasers. UV doesn't seem to overly bother me.
 

paul1598419

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Shorter wavelengths scatter more in the air so the beams appear more visible. Rayleigh scattering is the cause. I personally find 405nm bright, but not visibly in a direct sense. It strains my eyes like a powerful blue etc but the overall purple glow isn’t that bright to me. Most of the brightness comes from the materials it’s fluorescing.
I also find it difficult to focus my eye onto.
Shorter WLs do scatter more in the air than longer ones, but this pertains to sunlight and our atmosphere. In the short distances we are using lasers, this scattering is not at all noticeable. It is why the sky is blue and sunsets are red.
 

dressur4

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I don't know. I see it well,,,, I really don't like that color by it's self I don't know how "good" it is for our eyes. My favorite colors are 473nm and 532nm. I think the 405 would be great for florescence. but just never liked that color When they were first talking about BLueray I thought the laser was blue like 473ish or so,, not purple. I was quite disappointed when I first saw that color and yes it annoys my eyes. but hurt. i don't know if it does or not. I don't have one myself and not in a hurry to get a 405nm laser Unless i could pump a dye laser with it.
 

thanhtung

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I see beam violet laser very well, i used sj06 and bdr209, MM diode, very bright!
I like violet, it is so nice in night
 




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