Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

How to Register on LPF | LPF Donations

250mW Red E-Bay Laser for Real?

U

Ubbers

0
Joined
Aug 24, 2007
Messages
8
Points
0
I'm a newbie who recently won a Red 250mW E-Bay laser.
Guess it's apparent I'm a newbie since I took the listing's bate.
I haven't received it yet. There's another now for sale on E-Bay
by Lee_Math.

Looks like a "Changshu A-Laser Tech" laser, the kind Spymodex
offers. But, theirs only goes to 200mW.

The writeup for the one I bought says:

  Continuous output power:  250mW class 3B
  Peak output power:  300mW
  Laser diode:  1 watt
  Power:  2 X CR123A batteries (included)
  Duty cycle:  80 seconds on 10 seconds off
  Laser life:  Up to 10000 hours
  Wave length:  650nm

Once I receive the laser, is there a way to confirm the
specs without expensive thermal and spectral tests;
Ie, a marking on the laser diode or a "will light a
match at 20ft" test?

Any other comments, however disparaging, I'd
appreciate too.

Many Thanks, Ubbers
 





Rough man! Hopefully it is 200 mW, or around there. Ebay isn't reliable for lasers as you probably just realized. If it doesn't satisfy you, you should contact the seller and see if he will take it back. I hope it works out for you!
 
The ONLY thing I can say about it is this - they do not use a pump diode....the write up on that auction, and on Spymodex's site are WAY off ! You should thoroughly enjoy it when it arrives, but if they are the same type as the ones I ordered, you should definitely send it off for testing before the return period is up - just to make sure it is putting out what is advertised !

G !
 
Thank you for the helpful advice. I feel
better after reading your comments.
Three questions if I might:

1) Where can I get the 250mW spec tested?
The seller also said it has a divergence of
<0.5mRad.

2) Anywhere to buy protective glasses for
less than what seems to be the $40 dollar
going rate?

3) I dare to ask . . . what was the group
buy price Senkat negotiated? If it was
under $150, I might use this laser on
myself !

Many Thanks, Ubbers
 
something stands out. how would you use this laser on yourself?
 
I meant that as a joke of sorts: use it on
myself if I overpaid. "Use it on myself"
wasn't meant to make any sense in itself.

Truth is I purchased this red laser thinking
it would make a better star pointer than
my 5mW green. Once in awhile a moth
would fly by, intercept the green beam,
and the flash would set back night adjusted
eyes. I thought red would be less inclined
to do this. Of couse to get a visible red
650nm beam, much higher power is required.

Recently, however, I've become concerned
that anything much above 5mW may not
be safe to have at a star party. Hmmm?

Thanks, Ubbers
 
Ubbers said:
Truth is I purchased this red laser thinking
it would make a better star pointer than
my 5mW green. Once in awhile a moth
would fly by, intercept the green beam,
and the flash would set back night adjusted
eyes. I thought red would be less inclined
to do this. Of couse to get a visible red
650nm beam, much higher power is required.
Click to expand...
Well, if that thing really is putting out 250mW, you might just vaporize that moth instead of being blinded.
 
Unfortunately a red laser is not a good starpointer. In all likelihood, the red you bought will have a less visible beam than your 5mW greenie. Starpointers are pretty sweet in the ~30mW green range though. You may want to contact atlasnova.com about one of their high spec greenies.
 
Might anyone have a lead on two earlier questions:
1) Where can I get a 250mW laser tested?
2) Anywhere to buy protective goggles for cheap?
Again, thank for the helpful comments,
Ubbers
 
Well to answer those questions.

1) Depends which side of the pond you are on and trusting one of our members to do it for you. You would probably have to pay postage both ways. If you are in the US then we have the likes of Senkat who can check that for you and a few others have meters too like Pseudo and Hemlock_Mike to name a few you would have to ask them nicely (; If you are UK based then there is Myself and I believe Timelord has a meter too. If you are in the EU then not sure sorry unless you sent it over here........

2)Cheapest place would probably be Wicked Lasers but you dont want the Sport ones as even though they look cool you cant see the dot at all, you are much better off with the normal shades as you can see the dot so you know where you are aiming.....

Hope that helps.

Martin
 
Ubbers said:
Might anyone have a lead on two earlier questions:
 1) Where can I get a 250mW laser tested?  
 2) Anywhere to buy protective goggles for cheap?
Again, thank for the helpful comments,
Ubbers
Click to expand...

Well, sorry if this sounds a bit harsh, but I'll tell you from the start that that laser won't hold up 250mW. To get the laser tested you may want to check if a local place like a university has a laser power meter to test it for you. Other than that, Merl answered it all.
 
Thanks Merl and pseudonomen137,

I'm in America, Pennsylvannia to be exact. I'd be quite
grateful if a fellow member would be willing to test the
laser's power level. Of course I'd handle all shipping.

I'll try out Wicked on the goggles.

Oh, and Thanks SenKat. You mentioned this laser
isn't a DPSS one. Is there a site I can refer to learn
more about pumped and non-pumped reds?

Thanks Again, Ubbers
 
I believe all reds are directly injected diode laser (At least for pointer class), and not pumped through a crystal like the green, blue, or yellow laser...
 
I just see the ebay pages for specification of these laser, it is wrong. How can direct injected 1W laser diode only produce 250mW power?
It should produce close to1W even if they underdrive it to extend diode life.
 
Bernhard said:
I just see the ebay pages for specification of these laser, it is wrong. How can direct injected 1W laser diode only produce 250mW power?
It should produce close to1W even if they underdrive it to extend diode life.
Click to expand...

Bernhard, I believe the 1W figure is the electrical power fed to the LD and the 250mW figure is the optical output. Unfortunately, the remainder is given up as waste heat. The percentage seems to be in the right ballpark.
 
You must log in or register to reply here.


Back
Top