Newbie needs help :3

[Rachm]

Hey,

So I live in a country that doesn't allow lasers >1mW (have a guess ) and I recently acquired a laser when I went on an international trip. The pointer sticker claims to be 500mW but I highly doubt that. Without buying a meter whats the easiest way to approximate the mW? I mean I've only used it outside and I can see the dot over 5 kilometers away (3 ish miles) and after that there inst anything I can aim for. It's a standard 532nm green (dpss?) laser pointer and I can't really open it to get a look at the diode either as the casing is all sealed off. If I want to use it indoors, e.g. just pointing at walls etc. Do I need to buy safety goggles/glasses for that?

Cheers!
Rachm

 

[Eudaimonium]

Having glasses is ALWAYS highly reccomended, regardless of your laser's actual power.

If it'll pop a balloon, it's above 50mW.
If it'll burn a match without additional focusing optics, it's above 100mW.

Not sure about other possible comparisons.

 

[Lazy Laser]

Do we have another Aussie on the forum? :na:

 

[DrSid]

Glasses for indoors should be used. On the other hand if you are careful (as for example with loaded gun), you can do without. Don't point on glossy, glass, or metallic surfaces, and if it really is 500mW, not even bright or white. Still .. you only have one pair of eyes.

As for simple power check, try this. Focus it to smallest possible point at distance about 25cm/10 inch (use magnifying glass if you cant focus the laser itself), and burn through common black thin CD case. Measure the time.
200mW laser should burn through in roughly 10 seconds. 500mW at about 4 seconds. It's very poor precision device, but it should give you an idea.

On the other hand, for burning the glasses are especially useful. If you can't use them, use only black target, don't stare at the dot, and don't look from close.

Everything depends on how strong the laser really is. 500mW is pretty strong, and I would not turn it on without glasses. 100mW on the other hand is fine, as long as you are careful. But even there, the glasses are pretty useful, because accidents DO happen, as every laserist will tell you.

 

[Rachm]

I may or may not be Australian Well see, I took a chance as I knew I may not get it through customs so I bought a cheapie in China. It's a heck of a lot more powerful than a 1mW that I am certain of However, how do I focus it? I'm new to this. Do I need to open it up?

 

[DrSid]

No, do not open it .. some lasers have focusing knob. Some don't. Looks like yours is the second kind. You can use the magnifying glass then, but look out for reflections.

 

[Toke]

It it was cheap it is not likely to be more than 30-50mW.

The "cheapie" modules are 12mm in diameter and go from 5mW to 150-200mW, the higher end tend to be more expensive even though they look the same.

If you want more power than that you have to get the next size up in module, they are 30-some mm in diameter and do not sell cheap.

Even if what you got is "only" 30mW it is still plenty to give you permanent eye damage even from a reflection, so be careful.

 

[Lazy Laser]

Feel free to post some pics

Welcome to LPF :beer:

 

[Rachm]

Hey, yeah I'll post a few pics. I'm not gonna open it but it does have an thread/barrel head which you can attach with. I mean it came with one of those attachments which just makes cool patterns.

Cheers for the welcome!

Here's some photos, forgive the poor iPod image quality, and this was done in full daylight so its not the brightest laser..

 

[InfinitusEquitas]

There is absolutely zero chance that laser is 500mW. I have several lasers exactly like that.

Most likely it is in the 30-50mW range. For pointing at night, that's more than enough.

Welcome to the forum

 

[Haloid95]

Nice laser. But sorry i doubt its even 100mW. Its still good for night pointing. And you can probably still burn or pop balloons with it. But its defiantly not a 500mW laser.

 

[Rachm]

Haha yeah, I already knew it was nowhere near 500mW. I kinda guessed it would be around 30mW - can I attach something on the front to focus it?

 

[chipdouglas]

just stick to the advice in post number 2

michael.

 

[InfinitusEquitas]

Haha yeah, I already knew it was nowhere near 500mW. I kinda guessed it would be around 30mW - can I attach something on the front to focus it?

Personally I find a jeweler's loupe to be a very handy aid for burning things. Any magnifying glass should do though.

Just be careful about reflections off of the glass.