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ArcticMyst Security by Avery

For sale[ch65281]200+ green laser pointer

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Aug 17, 2007
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$411 for a 300mw is actually pretty high. There are suppliers I know that can sell for under $250. I would post the website that has a list of hundreds of manufacturers, but I don't want to ruin this person's thread.
 





H

High_Octane

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verybigkitty said:
$411 for a 300mw is actually pretty high. There are suppliers I know that can sell for under $250. I would post the website that has a list of hundreds of manufacturers, but I don't want to ruin this person's thread.

PM me with that link please.
 
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verybigkitty said:
$411 for a 300mw is actually pretty high. There are suppliers I know that can sell for under $250. I would post the website that has a list of hundreds of manufacturers, but I don't want to ruin this person's thread.

You must understand a key difference though:

Lasers that are called >300mW, and actually output >300mW, cannot really be had for <$500.

Lasers that are called >300mW, and actually output <50mW. THOSE can be had for <$250, or $411.
 
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Nov 8, 2006
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I can't believe you guys would fall for the old "spymode up the tail pipe" trick so to speak.

There is no way this laser can sustain 200mW for more than a few milliseconds at turn on.
In Fact I doubt they can produce even 100mW.
This was one of the original "ebaysers", I got one that looked exactly like this around a year ago. I posted about it on the CPF, I'll have to search my posts to refresh my memory as it wasn't a memorable product. I don't recall what I got out of it, but it wasn't much. It might impress someone who doesn't know what 100mW really looks like.
The entire laser was only about 4 inches long (about the length of 3-4 of the cr-123 cells) and only weighed in at maybe 3-4 ounces. It had very little mass to it.

I can hardly wait for one of our forum members with a meter to do a review of this, chew em
up and spit em out.

I'm not sure where someone thought that a diode pumped green laser had 20% efficiency?
No that I've come across have ever exceeded ~8%.
For instance, an RPL-350 running at 370mW with it's current tuned for maximum efficiency of say current level 4 would have around 1.4Amps of current running through the laser with a cell voltage of 3.8v (fully charged cell is 4.22v) would be a power consumption of 1.44x3.8=5.47 Watts. If the laser is outputting 370mW, then the efficiency is 0.37/5.47=0.0676 or 6.7% efficiency. Thsi is about the ballpark for all the diode pumped solid state CW green lasers. This number changes up or down a little bit depending on crystal quality and it's doping, but it doesn't exceed 10%.

So, lets work the math backwards to see if it's possible.
200mW output and lets say 7% efficiency to give them the benefit of doubt. 0.2/0.07=2.857 Watts that the laser would consume and the battery would have to provide. 2.857/3.0=952mA (this is a very conservative number on the current as when the battery is under load, it's not going to be operating at 3.0V, but something less.

I think if you take a look at the voltage under load and current curves of CR-123 cells in the CPF link above, you will find that the 1.0amp curve of all of these cells loads down the battery voltage to 2.5V or less. This would mean, the amount of current needed would be 2.857/2.5=1.14 amps of current. It appears that even using the best CR-123 in the CPF post it would be very difficult to get to get 1.14Amps @2.5V for any length of time. This makes 200mW of laser output from a CR-123 possible, but not for long. As for 250or 300mW, only in their dreams or if they leak IR and power testing is done with a lasercheck meter.

Jack
 
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pseudonomen137 said:
[quote author=verybigkitty link=1191467799/30#32 date=1191632612]$411 for a 300mw is actually pretty high. There are suppliers I know that can sell for under $250. I would post the website that has a list of hundreds of manufacturers, but I don't want to ruin this person's thread.

You must understand a key difference though:

Lasers that are called >300mW, and actually output >300mW, cannot really be had for <$500.

Lasers that are called >300mW, and actually output <50mW. THOSE can be had for <$250, or $411.
[/quote]
Hi Verybigkitty,
I agree with Pseudo completely.
Go ahead and buy one of those lasers and see the crap that arrives and fills your hand.
There are many websites that have these hundreds of "suppliers" or perhaps I should say scammers; alibaba, tradekey and others. The real lasers that perform and the companies that supply them won't be found in these scammer websites. If you want to find them, go to one of the big photonic conventions that are held several time each year, that's where you find the real deal.
\
Jack
 
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Jan 8, 2007
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woah... what?

bootleg2go said:
There are many websites that have these hundreds of "suppliers" or perhaps I should say scammers; alibaba, tradekey and others.


Sunny said:
Hey, everyone
You can find our company at alibaba.and our website:
http:\\www.laserpointer.en.alibaba.com
http:\\www.boblaser.com
You can find our products picture and specs

EDIT:: Just checked out their website. It's a nice website with a lot of flash and sound effects, but the laser themselves, from what I saw, are all IR spewers
 

elitex

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Sep 22, 2007
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Sunny's translated English shows he is a foreign supplier, possibly in China, judging by the way he phrases his messages. He won't send it to you because he knows you will break this item down and find it's real source. I'll bet he is a seller/reseller of re-branded equipment. He is hiding something. He is looking for someone who won't go deep-digging.
 

Sunny

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Sep 16, 2007
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Hi guys[ch65292]
Fistly I must apologize to everyone that I have not introduce myself till now.I am Sunny Liu[ch65292]from Bob Laser CO.,Ltd.in Guangzhou[ch65292]China.I am a girl[ch65292]just gratulated from the university[ch65292]then now as a foreign trader in our company.Our company manufacture and develop the laser.So everyone[ch65292]please do not suspect me hiding something and our company credit.I just come across this forum and I want to learn from this forum.
Secondly[ch65292]I come to this forum mainly learn and know more about the laser.I will not cheat anyone to buy our products.I put pictures mainly for you enujoying the picture.Of course this does not exclude that I am aslo willing to sell our products.But this must be baseed on our trusting each other.
So do not guess that I am hiding somthing or I am a cheat.
 
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Oct 7, 2007
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If your company is based on trust then you all should have no problem shipping one to senkat so that he can test it out. You just need to trust us before we can trust you because we are the ones that may spend alot of money. its common business knowledge.
 

mw1111

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Oct 8, 2007
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they are nice lasers, mW like, but until someone tests it out here i would not expect sales unfortunately sunny liu, sorry
 
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Oct 31, 2007
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i personly would not touch anything made in china with a barge pole!!! (some products excepted,like runners) in my other interest ,drag racing , we have a huge problem with chinese copys .they will bye a top class product ,msd ignitions,callies cranks etc and just copy it in their factories.the parts look pretty good but fail when the heat is on!.

caveat emptor ;)
 




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