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Confirmation of cancer causing properties for 445nm please

Lumify

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I agree on the brightness. They said blue LEDs appear most visible to human eyes due to rods and lalala. I find this true. My sisters phone charger has a blue LED which glows the whole fricken hallway! I should ask if she has any sleep issues :p The chargers bright blue led right next to her bed XD

Blue isn't the most visible light to the human eye. Green is. I believe 445nm might be the least visible wavelength that is commonly used in lasers with the exception of blu-ray (405nm). Here is a graph of the eye's response to light of all wavelengths.
25442d1265045018-looking-build-laser-read-me-v_lambda.jpg

I got that from MFO's laser building guide. These diodes are still really really bright for the price because they put out 1 Watt.

I haven't hear anything about blue light giving you cancer, but I've read that it's the most damaging to the eyes. Read up on the blue light hazard for more info. :beer:
 



Tanamil

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Expecting the beam/dot to be about as bright as a 100mW green laser. Wonder if this is accurate...
 

kevinmassey

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It all depends on if it's light or dark. If it's light then the 100mw green would appear brighter than 500mw of blue. If it's dark 500mw of blue would appear much brighter than 100mw of green IIRC.
 

brtaman

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Expecting the beam/dot to be about as bright as a 100mW green laser. Wonder if this is accurate...

In twilight 800mW of 445nm blows 100mW of 532nm out of the water...

The beam is very very bright. I was very pleasantly surprised. Only thing green has going for it is better divergence and tighter beam specs.
 

Morgan

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Hell, of all of the things out there that for a fact cause caner, this is what you're worried about? I wonder what % of the suns rays contain wavelengths of 445nm.

Stop being paranoid :p

Certainly not being paranoid mfo. I for one didn't for a moment think they could cause cancer due to it's unique colour but when the media get a hold of that sort of tag line then it tends to freak everyone out. Personally I'd be more worried about dying from being beaten with the thing than exposing my skin to the light. :D

In response to the request for a link, here it is. Fourth paragraph down it mentions the, 'C', word. (You should take some time to read some of the comments left by people. Alarmist or what! Someone suggests locking you away for 10 years for just possessing one! Click the, "Buzz up", icon at the bottom of the article.)

Deadly 'Star Wars Lightsabre' Sold To UK - Yahoo! News UK

As I said, I am not in the least bit worried but I'd like to be sure of my facts when I tell people this is propagandist tripe!

Thanks,

M
:)
 
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pullbangdead

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Blue isn't the most visible light to the human eye. Green is. I believe 445nm might be the least visible wavelength that is commonly used in lasers with the exception of blu-ray (405nm). Here is a graph of the eye's response to light of all wavelengths.
25442d1265045018-looking-build-laser-read-me-v_lambda.jpg

I got that from MFO's laser building guide. These diodes are still really really bright for the price because they put out 1 Watt.

I haven't hear anything about blue light giving you cancer, but I've read that it's the most damaging to the eyes. Read up on the blue light hazard for more info. :beer:

As mentioned, that curve isn't always true, that's the sensitivity curve for photopic vision and applies when in full light. In low light conditions, ie at night, vision is scotopic, which shifts maximum light sensitivity lower in wavelength, towards blue. Not all the way to blue, but towards blue.


ps- I hate biology. Living things make no sense.
 
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charliebruce

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In response to the request for a link, here it is. Fourth paragraph down it mentions the, 'C', word. (You should take some time to read some of the comments left by people. Alarmist or what! Someone suggests locking you away for 10 years for just possessing one! Click the, "Buzz up", icon at the bottom of the article.)

Deadly 'Star Wars Lightsabre' Sold To UK - Yahoo! News UK

As I said, I am not in the least bit worried but I'd like to be sure of my facts when I tell people this is propagandist tripe!

Don't let my mum see that article! :crackup:

For better of for worse, whenever a news article mentions cancer, it will always get read, hyped and taken out of context (and sell copies, and get ad revenue!) - the serious point behind my less-than-serious video. I wouldn't normally even venture into the comments section on most sites, but in this case I guess it shows how the great unwashed perceive our hobby.

Makes me wonder what Wicked's motivation really was...
 

mfo

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It's just weird how we're worried about a laser causing cancer, which is something we pretty much receive zero exposure to when we compare it to everything else in life that we're exposed to much more frequently and on a daily basis. Toxins in foods we eat, pollution in the air, pollution in our water supplies, smoking, etc.
 

Morgan

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It's just weird how we're worried about a laser causing cancer, which is something we pretty much receive zero exposure to when we compare it to everything else in life that we're exposed to much more frequently and on a daily basis. Toxins in foods we eat, pollution in the air, pollution in our water supplies, smoking, etc.

When you say, "We", do you mean us here at LPF or the wider, "We", of the general public?

I genuinely don't think any of us here are worried by this. It's another example of the mythology attached to misunderstood technology such as lasers. There's another thread, (by cmak I think), that says someone should do something and if I chose to be that someone then I would like to dispell some of these myths.

I agree, there are far more dangerous long term exposures to other everyday hazards, and all these things should be kept in perspective. This one is relevant now and I, for one, would like ammunition to quell the fears of an uneducated public. The eye hazards of this laser are not really any different to other high powered lasers already on the market that are currently less strictly regulated, (in the UK at least). Of course distance; severity and; likelyhood of damage are increased but blind is blind! You start to add cancer in there and the legislators will start listening just because of that one word.

This thread has provided me with some ammunition so I'm happy it's another job well done by the community. Thanks everyone...

M
:)
 

Benm

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445 nm light is not inherently danagerous. We are exposed to it all the time, even the blue pixels in the computer screen you are looking at right now, emit light in that frequency range. For many of us this means exposure many hours a day, each and every day, with no known carcinogenic effect.

When you go to the point of intensities that burn skin, things change obviously. Essentially there is a plausible mechanisms for burns to increase cancer risk in the future, but this is not specific or limited to light/lasers at all. Even if you burn your skin on a flame, or a hot oven dish, there is some risk involved. Any burn that leads to scarring can possibly have adverse effects on the long term.

Lets summise to say that playing around with a 445 nm laser without actually burning yourself is less dangerous than spending even a short while tanning on the beach without being covered in sunscreen top to toe. Even casual exposure to sunlight (like walking around town on a sunny day) poses a greater risk - so if you must worry, worry about that first.
 




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