I never had any laser pointer before and last Tuesday Oct 5th I ordered one green 200mW pointer at Amazon for $40.67 after shipping. It came today and I played with it in my back yard before and after dark. It's bright but I don't know it's as bright as 200mW or not, how to check? I pointed at the tip of a power line post about 500' away: my Tiablo A9 with aspheric lens is doing the same but this green laser is much, much, much brighter and smaller spot. I just wonder it's true 200mW or just about 30mW or even 5mW.
Just got my first laser pointer from Amazon: 200mW Class IIIb, is it that bright?
- Thread starter TDKKP
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AnAppleSnail
Flashlight Enthusiast
Be careful with those. You can cause eye damage pretty easily. 200 mW in green is pretty freakin' bright.
I hope it's a 200mW not the 5mW. I don't have any laser to compare to find out.
black_ice_pc
Newly Enlightened
Due to the nature of green lasers, they are more dangerous than your typical red pocket laser for a few reasons:
1: Power
Anything over 5mW poses certain risks that REALLY need to be understood. Due to the nature of a laser, all the light (theoretically at least) travels in a straight line, whereas a flashlight beam is scattered light aimed in a certain direction by a reflector. The straight line pattern of a laser makes it much more dangerous, because if it hits your eye, the light will be focused into a very small point and can easily cause permanent damage. You must be VERY careful to not shine it on anything reflective that might cause the beam to bounce back into your eyes. With a laser this bright, even shining it on a wall in your house and looking at the dot can cause damage.
Here's a way to reference the power of your laser. A 5mW green will have a slightly visible beam in the air. Not too bright, but still visible. ~50mW will have a clearly visible beam, even standing say 10' away from the laser. A 200mW is gonna have a very visible beam, and will easily hit low clouds. If this is your first laser, don't be too bummed if it's not actually 200mW. It could be a good thing, since lower power is always safer.
2. IR. Green lasers emit light in a different way than a red laser does. They use a method called DPSS or Diode Pumped Solid State. Basically, the light starts out as infra-red, and is shined through crystals to halve the lightwave frequency to end up green.
This poses another risk though, because green lasers can put out IR light. This can be a bit wider than the beam, so you could be shining IR into your eyes and not even know it! Most cheaper lasers like the one you bought do not come with an IR filter to block IR from escaping. If you have a camera with "night vision" you can check to see if your laser is putting out IR. Switch the camera to night vision and shine the laser at it. DO NOT stand behind the camera, or you might accidentally end up hitting yourself. If possible, just record for a moment and then look at the tape.
Just remember, a laser like this is not a toy to be shined at people or at cars etc. That's a felony, in case you didn't know. I can't stress enough how important it is to not screw around with a high powered laser.
Anyway, I'm done ranting lol
. If you want more info, go check out laserpointerforums.com. That's the place for all things lasers.
1: Power
Anything over 5mW poses certain risks that REALLY need to be understood. Due to the nature of a laser, all the light (theoretically at least) travels in a straight line, whereas a flashlight beam is scattered light aimed in a certain direction by a reflector. The straight line pattern of a laser makes it much more dangerous, because if it hits your eye, the light will be focused into a very small point and can easily cause permanent damage. You must be VERY careful to not shine it on anything reflective that might cause the beam to bounce back into your eyes. With a laser this bright, even shining it on a wall in your house and looking at the dot can cause damage.
Here's a way to reference the power of your laser. A 5mW green will have a slightly visible beam in the air. Not too bright, but still visible. ~50mW will have a clearly visible beam, even standing say 10' away from the laser. A 200mW is gonna have a very visible beam, and will easily hit low clouds. If this is your first laser, don't be too bummed if it's not actually 200mW. It could be a good thing, since lower power is always safer.
2. IR. Green lasers emit light in a different way than a red laser does. They use a method called DPSS or Diode Pumped Solid State. Basically, the light starts out as infra-red, and is shined through crystals to halve the lightwave frequency to end up green.
This poses another risk though, because green lasers can put out IR light. This can be a bit wider than the beam, so you could be shining IR into your eyes and not even know it! Most cheaper lasers like the one you bought do not come with an IR filter to block IR from escaping. If you have a camera with "night vision" you can check to see if your laser is putting out IR. Switch the camera to night vision and shine the laser at it. DO NOT stand behind the camera, or you might accidentally end up hitting yourself. If possible, just record for a moment and then look at the tape.
Just remember, a laser like this is not a toy to be shined at people or at cars etc. That's a felony, in case you didn't know. I can't stress enough how important it is to not screw around with a high powered laser.
Anyway, I'm done ranting lol
. If you want more info, go check out laserpointerforums.com. That's the place for all things lasers.black_ice_pc
Newly Enlightened
One more thing. In all likelihood that laser is probably only putting out 30-50mW of green. The rest might be IR, or just a plain lie. Don't sweat it though, that's not too bad of a price. For future reference, you can get tested true 50mW green lasers here. They're a well known source for cheap but good greens. I have 3 and all are great.
glockboy
Flashlight Enthusiast
If it's true 200mW you can burn a match easy.
Good summary by black_ice_pc.
I measured a number of laser pointers that were confiscated by the local police, and almost all of them had significant IR emission, in some cases way more than the green. If you have a red filter (preferably glass, but plastic might also work) you can use that to block the green light and look for IR with a night-mode camera.
The IR is typically 1064 nm which is completely invisible to the eye, but will still cause rapid eye damage given enough power. What happens is that the retina is cooked. Double-plus ungood, so be careful.
Disclaimer: I am a laser spectroscopist.
I measured a number of laser pointers that were confiscated by the local police, and almost all of them had significant IR emission, in some cases way more than the green. If you have a red filter (preferably glass, but plastic might also work) you can use that to block the green light and look for IR with a night-mode camera.
The IR is typically 1064 nm which is completely invisible to the eye, but will still cause rapid eye damage given enough power. What happens is that the retina is cooked. Double-plus ungood, so be careful.
Disclaimer: I am a laser spectroscopist.
black_ice_pc
Newly Enlightened
You are correct about the legality. If customs finds the laser, they'll keep it. However, they typically get through pretty easy.
Anything over 5mW is in a different class of laser, either 3B or 4. For a 3B laser to be legal, it has to have certain safety features and have certification from the feds as legal. The safety features are:
A shutter over the aperture that must be opened to use the laser.
A key switch that must be turned on.
A momentary delay main switch, that delays 1 seconds after pressing for the laser to fire.
An LED to show when the laser is on.
That's all I can remember, but the point is the common pen style lasers have none of these.
So while they are illegal, most companies will still ship them. It's just rolling the dice to see if it makes it through customs or not, but typically it does with no problems.
As for coupons, AFP004 will get you 15% off $60+, or YABEPG will get you 10% off any order. I should also point out that, if I recall correctly, their greens do come with an IR filter, so there's none of that nasty IR to deal with, it's 50mW of straight green photon goodness
.>Anything over 5mW is in a different class of laser
I think classification is (also) done according to the possibility of the laser beam to exit the enclosure, that is, a 100 W laser could technically still be class II or whatever as long it is in a light-tight enclosure (and has all the safeties you mention). Take blue-ray burners for example----high laser output but still not class IV.
I think classification is (also) done according to the possibility of the laser beam to exit the enclosure, that is, a 100 W laser could technically still be class II or whatever as long it is in a light-tight enclosure (and has all the safeties you mention). Take blue-ray burners for example----high laser output but still not class IV.
About testing IR leaking: are you talking about using a camcorder or a camera? If it's a camcorder more details how to test: record a moment with the laser beam directly on the lens or slightly off? What's the distance bettween them? How long is good enough to check the recording and what I need to see it's leaking or not?
I check mine in house last night from wall to wall and I can see easily the beam at 25' in my lighted room. I guess mine is much more than 5mW just don't know how powerfull it is. I also ordered the 50mW at LED Shoppee to compare when it arrives, how long will it take to the US?
I check mine in house last night from wall to wall and I can see easily the beam at 25' in my lighted room. I guess mine is much more than 5mW just don't know how powerfull it is. I also ordered the 50mW at LED Shoppee to compare when it arrives, how long will it take to the US?
If you want to check the power of a laser, the only accurate way is to use a meter for the purpose. Kenom and Laserbee are the most prevalent for the non-professional. If you are in southern Alberta, you may borrow mine.
For reference, my <200mW O-Like actually measures 132mW total output with 12mW of that in the infrared. When focused, it will light a blackened match and burn through electrical tape quite easily.
For reference, my <200mW O-Like actually measures 132mW total output with 12mW of that in the infrared. When focused, it will light a blackened match and burn through electrical tape quite easily.
I just did a little test at work. I change the batteries with 2 new AAA Duracell Alkaline at Costco, put 2 books about one foot apart connected with electrical tape, hold the laser about one inch above the tape with support of my left hand to make it steady as much as I can. Close my eyes, push the button and count to one hundred and stop. All I can see is a little smoke and some smell of it, that's it, no hole or burnt area of anything I can notice.
So I guess mine is no where <200mW but how much: 10mW, 20mW, 30mW, ...???
So I guess mine is no where <200mW but how much: 10mW, 20mW, 30mW, ...???
black_ice_pc
Newly Enlightened
hcb is correct about classification. I was talking about pointer classification, but there are definitely other things to take into account in a different application. TDKKP, I was talking about a camcorder. It has to have a "night vision" mode to use in the dark. The night mode means it doesn't have an IR filter in the camera. Set the camera to record and shine the laser slightly off axis at the camera, so the dot isn't shining in the lense, just right past it. IR looks white with a little pink in it on a camera. If you see any color besides green from the laser on the recording, it's IR.
Based on the smoking tape but no cutting, I'd say it's probably around 100mW. The thing about pen style pointers is the focus is fixed(unless you open it up), so you can't get the dot super small. The smaller the dot, the better the burning etc. But I'd guess it's in the 100mW range. Try popping a black balloon or a balloon with a black dot sharpied on it.
Based on the smoking tape but no cutting, I'd say it's probably around 100mW. The thing about pen style pointers is the focus is fixed(unless you open it up), so you can't get the dot super small. The smaller the dot, the better the burning etc. But I'd guess it's in the 100mW range. Try popping a black balloon or a balloon with a black dot sharpied on it.
Mjolnir
Flashlight Enthusiast
- Joined
- Dec 19, 2008
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If you use something as a diffraction grating, like a CD, the IR component of the beam will be diffracted differently than the green because of its longer wavelength.
Here is an article about how to do it:
http://www.wired.com/wiredscience/2010/08/laser-pointer-hazard/
Here is an article about how to do it:
http://www.wired.com/wiredscience/2010/08/laser-pointer-hazard/
Astroscanner
Newly Enlightened
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When did you order from Ledshoppe ?
Did they give you a tracker number yet ?
If so does the tracker number say if it has left China yet ?
I ordered last week Oct 14th. Five days later Oct 19th they emailed me order has been ship but no tracking number so may be another two weeks I'll receive it.
Astroscanner
Newly Enlightened
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I placed an order on Oct 11 and got an email on Oct 13 saying it was shipped registered air mail Oct 12, but when I input the tracking number it would not give any results.
I had heard that Hong Kong post office can be slow in processing so I kept trying the tracking number for several more days.
Well after emailing the company on Monday October 18th to check if my tracking number was accurate I received a reply today where they said:
"Thanks for your contact. You package was returned from the post office by some reason. Please confirm the following shipping address and we will send it to you again. Thanks for your patience and understanding"
So if when you get a tracking number it just does not show up in the system after several days it might be good to have them check and see if your tracking number was correct and if so why it is not showing up in the postal tracking system.
This is my first order with them but I have read several positive comments about them from others on forums so I am feeling like things should be resolved ok.
(I'll see about posting how it turns out)
I keep looking at the green lasers on amazon, they seem to be very inexpensive compared to some other places. But I worry about the quality? I don't seem something especially great to just point at my powerpoint/keynote slides, but it'd be a pain if my pointer dies in the middle of a large conference! Are the lasers on amazon usually regarded as being OK, or should I go to a specialist store?
Thanks!
Thanks!
black_ice_pc
Newly Enlightened
Wherever you buy from, don't get anything over say 15mW for presentations, 5mW would probably be better. Bouncing lasers off a white surface and staring at it calls for a low power laser so as to not fry your eyeballz .
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