Can you see the beam of a Blu-Ray or Blue laser?

[Hydrogen]

The title explains it really, I can see the beam my 1mW green laser in daytime, I think it is overpowered, but anyway can you see the beam of a blue laser?

 

[anselm]

BluRay is not very visible, at least on low power, but in darkness it is visible if you
look carefully. A blue laser (445nm or even 478nm) is much more visible than 405nm,
but still not as much as 532nm?

 

[Hydrogen]

Thanks, also another question, at what power of mW does a laser start damaging you eye from diffuse reflections?

Thanks for the fast reply also.

 

[joeyss]

It depends on the the % reflected. Most are around reflections are 5-10% ( except a mirror.) so anything over 40 or 50 can damage your eyes without a problem.

 

[anselm]

Might I suggest you use the search engine? All of your questions have already been asked and answered in the past...

 

[Hydrogen]

Didnt really find much.


And it seems you could give me a very good answer.

 

[DrSid]

You can't just say diffuse reflection is 5% to 10%. Good white wall or paper will reflect almost 100% .. but it will reflect it into all directions .. so the distance from the dot is important. From 1 inch yeah, even 50mW could be dangerous. From few feet no way. Class 4 lasers are usually thought dangerous for diffuse reflection, and they go from 500mW. But it really depends on the situation.

 

[Hydrogen]

You can't just say diffuse reflection is 5% to 10%. Good white wall or paper will reflect almost 100% .. but it will reflect it into all directions .. so the distance from the dot is important. From 1 inch yeah, even 50mW could be dangerous. From few feet no way. Class 4 lasers are usually thought dangerous for diffuse reflection, and they go from 500mW. But it really depends on the situation.

OK thanks, so if I had a 100mW green laser burning some electrical tape, it wont do no harm while looking at it?

 

[qumefox]

Electrical tape tends to be shiny, especially when it starts melting. It's always advisable though to use appropriate safety goggles when playing with lasers when there's even the slightest chance of dangerous reflections.

 

[Hydrogen]

Electrical tape tends to be shiny, especially when it starts melting. It's always advisable though to use appropriate safety goggles when playing with lasers when there's even the slightest chance of dangerous reflections.

I was messing around with a IR diode from a 1mW greenie, and my right eye has gone a little blurry.

 

[qumefox]

That... isn't a good sign. You'd best see an eye doctor ASAP. IR, at least in the range we're talking about, is especially dangerous. It fries your retina the same as any visible wavelength would, only since you can't really see it, it's hard to tell you've caught a reflection until after the damage is done.

 

[DrSid]

For any kind of burning goggles are recommended, as you will probably stare at it from close.

 

[Hydrogen]

OK then. My right eye isnt that bad, but I clearly have damaged it as it has gone slightly blurry.

 

[david1235102]

you should listen to qumefox; go get it examined by an eye doctor.
also, anything above 4.95mW has the potential to cause eye damage; but as others have said, it depends on the situation: reflection or direct hit to eye, wavelength (color), power output, etc.

 

[Krogith]

GOTO the Eye doctor ASAP like seriously unless you want that damage for the rest of your life. They can help you some but you really might of got some permanent damage. don't Mess around with things if you don't have the right protection.

What Are you doing?? looking into the diode to see if it was on?? If so thats a NO NO ever

 

[Hydrogen]

I didn't look at the diode, I looked slightly at the IR burning a bit of black tape, but there was no collimated dot, it was the bare diode, close up to a bit of black tape, still I'll see the doctor.