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ArcticMyst Security by Avery

Need help with battery choosing

Joined
Jun 4, 2010
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Hello,
I bought some days ago some parts to build a red laser:
Host
Laser diode
Diode driver
I read in the host information that I should use 2X CR2 Ultrafire battery for a red laser and this driver.
My question is - Do I need this battery or something else? (Because they meant that I should use it with driver that I didn't buy)
And I found this site to buy the battery. Is it a reliable shop?
Do you have another shop that offers this battery and charger?
Thank you,
Yuval
 





Joined
Feb 18, 2013
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I'm still new to this too, but I think you will need two batteries, because the driver you got is linear.
As for the ultrafire batteries, they should work.
Good luck.
 
Joined
Dec 31, 2012
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That host looks like it takes two (2) CR2-sized batteries. If you use actual CR2 batteries, those are 3.0V each, and together, will supply 6.0V, more or less.

I know this can seem confusing, at first.

Many of us use Lithium batteries in our pointers. They are reusable, rechargeable, and can supply lots of current. They are typically 4.2V fully charged. The 16340 battery is the same size as the CR2. Using two of those will supply 8.4V, and if your driver can handle it, it is a common combination among the highest output laser pointers.

Another Lithium battery, is the 18650, which is roughly the size of two CR2 or two 16340 batteries. Each 18650 supplies 4.2V fully charged. They are larger and can last longer between recharging.

I have both batteries in my collection. Sometimes, I run a pointer off one 18650 for lower output, and two (2) 16340s for balls-out maximum output.

The driver you linked looks like its designed for 1.5V max. I think you will have a problem with that driver, whether you use CR2s or Lithium batteries.

Search the forums. There is a great deal of discussion about drivers.
 
Joined
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I really don't know what to search, I just want to know if the laser diode can work with this driver and output 100mW and higher power.
I will be glad if you check it - I saw some info in this the laser diode page and the driver page in the shop's site. you just have to enter to the links I wrote and go a little bit down and then you will see some pictures and in one of them you have some information. Just tell me if this driver can work with this laser diode and what voltage I have to supply.
And I have some questions:
What is the meaning of "pulsed 240mW"? (See the info in the laser diode site, there I read this)
And in the info picture of the laser diode they also write in the limits "reverse voltage - 2v". What is the meaning of this reverse voltge? I it the max voltage the diode can handle with?
Thank you!
 
Joined
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Yes, the driver will drive that diode. I think it's a poor choice as a driver for a laser pointer. I just noticed that driver has a TTL input, in addition to the power. Typically, the TTL input is used to turn the laser on and off really fast using 0-5VDC. The most common application for TTL input is using the diode in a laser projector, with other colors. By combining the beams of different colors, and turning them on and off individually, we can change the overall color of the output beam.

I think a better driver is something like:

17mm Round Linear Driver - $8.99 : Mohgasm LLC, Have you experienced one lately?

This one can handle the 6V input better, and is simpler.

CW often mean Continuous Wave. It means operating the laser continually for some period of time, be it 5 minutes, three (3) hours, or all night. Some lasers, particularly DPSS lasers, are pulsed very fast, like 100 of times per second. By pulsing it, the laser does not heat up as much, and the output (per pulse) is greater than that achieved by CW.

In a laser pointer, the diode you've referenced will be operating in CW mode, meaning you can expect to get 100mW output @ 200mA. This presumes, of course, the diode will be properly heatsinked and/or cooled, so it doesn't cook, overheat, and die.

Good luck and keep us posted.
 
Joined
Jun 4, 2010
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I'm a begginer and this gonna be the first laser I build. I bought it with a driver because I want to purchase a 500mW 445nm laser diode from one of the forum members and firstly I want to try assembling a laser just like I'm going to do with this diode (I don't want to risk it as I'm still a noob). So this driver will give me 100mW output? (I want also to keep this red laser...) and I didn't understand - can I operate it with 6V?
And some questions:
How do you know what current the laser diode needs?
And just if you know - the CR2 batteries (6V total) can operate 500mW 445nm laser diode to max output?
And where can I buy CR2 rechargable batteries in good quality online?

Thank you very much.

Edit:
(read also the post)
I was sure that it was written in the diode's page that it outputs between 100mW to 200mW!
And now I saw that it was 200mA!
Do you know how can I calculate it?
And one more question:
I bought 10 pieces of this LM317 current regulator:
http://www.taydaelectronics.com/lm317t-lm317-voltage-regulator-ic-1-2v-to-37v-1-5a.html
Is it the type of LM317 that operates with 100 ohm potentiometer it is the one that operates with 200 ohm potentiometer?
 
Last edited:
Joined
Feb 18, 2013
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You can operate a 500mW 445nm on six volts, but it will not be max power. 2 16340 at 3.7v(4.2 full charge) is what you need for full power.
 




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