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I can see only little red light






Careful with that dim red light!!:eek:
It's actually rather powerful infrared laser light.
Very dangerous to your eyeballs, even if it looks dim to you!!
Don't be tempted to look "down the barrel".
 
The other possibility is that the diode itself has "burned out" where instead of putting out 800mw of 808nm, it's only putting out maybe 10-20mw of 808, which may not be enough for the crystals to do the conversion to 532.

I had this happen recently with a laser of mine that I purposely decided to push it as hard as I could - I was getting about 60mw out of it, but the poor little diode couldn't handle it and that's all that's left now is a faint little red light lol (Though if you use a webcam you can see that there's a LOT more IR light than your eyes are capable of seeing.)

Regardless - good advice all around is to not look down the barrel of any seemingly innocent laser :)
 
we seriously need a sticky about the dangers of IR light in greenies. just too many people having cheap Chinese ones burning out and looking into the apparent dim light (not sure if thsi guy has might've been caught in time).
 
True true.

And the worst part is, generally speaking, if you've lost sight in your eye because of an accident or looking down an IR beam without knowing it... You don't often know right away that you can't see in certain spots because you brain tries to fill in the blanks automatically. It's when you can't see something in your peripheral that you should be able to that you realize there's damage done. :(

Hopefully they're okay.
 
DO NOT LOOK INTO LASER WITH REMAINING EYE!!!
I think your laser was overclocked 100mW and pump diode died
 
I don't think that faint red glow is IR light.
The same thing happens to me if I push the button too gently ,there is no green light just faint red glow.
I don't look directly in to the barrel I look from the side.
Your problem could be bad electrical contact or broken switch.

Sorry for my bad English.
 
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robi500 said:
I don't think that faint red glow is IR light.
The same thing happens to me if I push the button too gently ,there is no green light just faint red glow.
I don't look directly in to the barrel I look from the side.
Your problem could be bad electrical contact or broken switch.

Sorry for my bad English.
Click to expand...

What other source of light is that "faint little red glow" going to be sir? You have an 808nm pump diode, 1064 crystal conversion which we can't possibly see, and then 532 out which is green.

So... The *ONLY* possible red that could exist is 808, unless your driver has a little red LED on it, but that's blocked behind the diode anyway.

Do you have an alternate explanation that doesn't involve suggesting it's not IR light and peering down the laser tube to see it? No the beam isn't directly pointed into your eye, but the fact that you can see it means it's reflecting off of something and yes... Is still getting into your eye.

You want to be sure it's IR? Use a webcam or something similar to look at this little red light and you'll see it's actually quite bright, and not so red.
 
enigmahack said:
What other source of light is that "faint little red glow" going to be sir? You have an 808nm pump diode, 1064 crystal conversion which we can't possibly see, and then 532 out which is green.

So... The *ONLY* possible red that could exist is 808, unless your driver has a little red LED on it, but that's blocked behind the diode anyway.

Do you have an alternate explanation that doesn't involve suggesting it's not IR light and peering down the laser tube to see it? No the beam isn't directly pointed into your eye, but the fact that you can see it means it's reflecting off of something and yes... Is still getting into your eye.

You want to be sure it's IR? Use a webcam or something similar to look at this little red light and you'll see it's actually quite bright, and not so red.
Click to expand...

Maybe crystals produce red light instead of green light when they are exposed to low intensity 808nm IR light or laser diode produces red light instead of invisible 808 nm when driven by very low voltage and amperage.
 
I just checked with my camera and it is "purplish" IR light but it is not much brighter than "red light" seen when looking bare eyed from the side ,IR light from TV remote looks far much brighter to the camera but is not visible to bare eyes .
 
Ok, I've been reading some recent posts like this and the lack of understanding on this forum is starting to irritate. I know that's how "noobs" can be, so please READ, READ, READ!

1. Don't ever buy from Chinese drop shippers! Their lasers above 5mW are absolute garbage EVERY time.

2. The red light is 808nm. It is the ONLY thing it could be. Again, READ! I would bet that the pump diode is burned out. That's what happens to low quality, mass produced, garbage. It is likely outputting 1-30mW of 808nm. Even though the power is "low," you should NEVER under ANY circumstances power up a laser while it is aimed at your face. That is just plain stupid!

3. Crystal alignment is almost never the issue. Now, the cheap China greenies are aligned very sloppy so they usually have terrible stability issues and ugly beams shooting off at a 20 degree angle from the aperture, but they will produce some green light even if the alignment is knocked off a tiny bit. If the diode was producing 800mW of 808nm, the spot would be visible on a near surface as a dim, cherry red and would be intense enough to irritate your eye if directly exposed. Also, cameras see 808nm and other near infrared wavelengths as a pale, purplish glow.

4. The crystals are coated for very specific wavelengths, so there is no way they could produce red light. That's just plain and simple bullshit. The only wavelengths you'll get from a DPSS green is 808nm, 1064nm, and 532nm.


Guys, please read the damned forum!
Refer to the Green Laser FAQ posted by Elektrofreak. It is stickied at the top of the Green Lasers section.
 
RA_pierce said:
2. The red light is 808nm. It is the ONLY thing it could be. Again, READ! I would bet that the pump diode is burned out. That's what happens to low quality, mass produced, garbage. It is likely outputting 1-30mW of 808nm. Even though the power is "low," you should NEVER under ANY circumstances power up a laser while it is aimed at your face. That is just plain stupid!
Click to expand...

My laser is not burned out it works normally when I give proper push on the button. I only see red glow when I push button too gently so his laser is not necessarily burned out maybe it is just a bad electrical contact or broken switch.
 
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