power - 3.0v - 3.7v OR 3.7v - 4.2v / battery

I found this ebay seller and they have one 30mW with 3.7 - 4.2v and another 30mW with 3.0v - 3.7v. (see links below for photo and description) So, what would be the difference with these, other than the +- connection point being wires on the 3.7v as opposed to spring and copper burl on 3.0v?
Would performance be the same, or would the higher voltage increase performance for pointing at stars?
And, what of battery's. If it is 3.7 i need 1x 3.7v battery right?
If it is 3.0v then i need 2x1.5v battery's connected in series yeh?

Q. Is 3.7v superior to 3.0v?

30mW 532nm Laser Diode Module/Green Laser/Laser Beam | eBay
30mW 532nm 3.7V-4.2V /Laser Diode Module/Green Laser | eBay

Well, there are lithium battery that are 3V, but if you usually use 3.7V Battery, it's better you stick with 3.7 V, Beacuse it's really easy to mess them up, I did that before, so I will try to keep them the same voltage without puttin them into the wrong charger.

and supposedly is 3V = 2 x 1.5v battey, but it's good to notice that most 1.5V battery wont' have 1.5V when you gives them loading.


I think it's not easy to answer your questions, but I think if the output is certainly 30mW, then they makes no differnece. But the currentl on the 3V should be higher than the 3.7.

Neither module is 'better' than the other. They're just designed to be used with different power sources. The 3v driver is designed to be used with 2x 1.5v batteries (AA, AAA, etc) while the 3.7v driver is designed to be used with a single li-ion battery.

If you try to run a 3v driver off a li-ion, all it does is make it run hotter and die prematurely. The 3v ones can be modified to handle a li-ion, all it takes is adding a diode in series, however, if there's already a 3.7v version of this module available, it's not worth the effort.

Like I said. It just boils down to how you want to power the module and nothing else.

This is good qumefox, thank you.
Help me a again please - this supplier sells a 200mW 3.7v - 4.2v module. Obviously best powered with 1x3.7v battery, as you explained above. But, it is made to fit into pen style holder which houses 2x1.5v aaa battery's. Can i power a 3.7v - 4.2v module with with 2xaaa 1.5v battery's? I understand that it is ment to be powered by 3.7v but can't figure out why they make it to fit in pen style holder with 2xaaa 1.5v battery's?
If i fit 2x3.7v battery's connected in series that will be overpowered, so, can't figure out how i would set in up in a two battery housing?

The modules are fairly 'standard' being 11.9 or 12mm. They're used in far more than pen hosts. You can use them in other hosts it just usually takes some modification. (bypassing the switch so it's always on, for use in a host with an end clicky is a good example)

Here are two 'non normal pen style' builds i've done with normal 532nm modules.





If you really want to put one in a 2x AAA pen host. About yoru only real option is to use a 10440 li-ion and a spacer, and only use one battery.

i do not want to put the 3.7v module in the pen style, but it looks like it is made for pen style, witht he button on the side. I can't figure out why they make them that way when it is designed for 1x 3.7 volt battery.
Anyway, i will wait until they arrive and maybe i wont be confused
when i have them in hand. Thanks again for the help.