Help with 3.5w

[NiteRyder]

hi, i need some guidance/help with my 3.5w laser, i had it built but dont have many details on it, and the guy who built it i cannot contact.
so if anyone can help that would be great.
1. i want more intensity out of my laser, how can i do this?
it burns but only up close. and is powered by 9v battery.
2. i cannot get it to focus to pinpoint, how can i do this?
ive tried changing lenses.


ive tried to upload pictures but no matter how much i resize they are still to big.

 

[Sta]

Your description does not seem to match a 3.5W laser.
A 3.5W should be able to burn at most distances, and there is no way it could be powered by a 9v battery. 9v batteries cannot supply enough current.
Could you please upload your images to imgur and then post the links?

 

[Chrisbee]

... And include your location in your sig.
It's hard to help if we don't know were you're at. Different countries have different options available.

 

[NiteRyder]

sorry, Melbourne Australia.

i was told by the guy who built it that it was only to be powered by a 9v battery or it would kill the diode.

see picture of the driver, the was also powered off the same 9v battery but i changed that to run on its own battery.

 

[Chrisbee]

There are some people on here that are also from Australia that could get you some better advise on where to source parts. But depending on how you found this guy that sold you that laser, it sounds like it's not what he led you to believe it is. Did he actually show you that it's putting out over 3 watts? Because it doesn't sound like it is. Also it's hard to tell from that pic, but that looks like it could be a cheap ebay sourced driver. For it to only be powered by a 9v and nothing else "or it will kill the diode" isn't right either. Although this is still speculation as you don't know any actual specs for this thing. You should post more pics of it first, so we can get a little better understanding of what you have. Since it looks like it mite be a project box type of a build, get pics of as many components as you can. especially the laser module and the lens.

 

[wmgeorge]

I am not even close to an expert level on lasers, but been a electrician and in ham radio for over 30 years. There is no way a 9 volt standard battery can drive a laser to 3 watts. Not enough current available. Maybe .3 of a watt?

 

[diachi]

I am not even close to an expert level on lasers, but been a electrician and in ham radio for over 30 years. There is no way a 9 volt standard battery can drive a laser to 3 watts. Not enough current available. Maybe .3 of a watt?

Yeah, a 9V power supply would work for sure, but those square 9V batteries have a relatively tiny capacity and can't really provide much current at all. Maybe that's what the guy meant, a 9V power supply instead of a 9V battery?

To answer your questions:

1. Technically if you want more "intensity" you'd focus the beam to the spot - what I assume you mean though is that you want more power. The short answer is: No. Chances are the diode is already being driven at full power - although without knowing which diode it is it's hard to say for sure. You could probably try turning up the current on the driver - or use a different driver if the one you have won' go any higher. But you risk killing the diode entirely if you do that without knowing what the maximum current should be.

2. Can you post some more pictures? You'd normally adjust the position of the focusing lens to focus it to a point (Which would also improve burning capabilities). If we can see how the lens is set up we may be able to tell you if that's possible with this laser and how to do it.

 

[wmgeorge]

Yes maybe a 9 volt power supply would work, or my other thought was the 9 volts a signal voltage to the driver? ... kind of a bit over the usual 0-5 volt.

 

[diachi]

Yes maybe a 9 volt power supply would work, or my other thought was the 9 volts a signal voltage to the driver? ... kind of a bit over the usual 0-5 volt.

Yeah, I've never heard of 9V being used for modulation. As you said, normally 0-5V. That driver may be fine with 12V - but it's hard to say without more information/pictures. Could just be that it needs more heatsinking on the driver to work at 12V.

 

[autonomousperson]

A 9v battery can put about 500mA. Without accounting for voltage sag, that is 0.5x9 = 4.5w. The power supply has a peak efficiency of 90% leaving you with 4.05w to the LD. LD probs has an efficiency of 25% so that would be 1w of output not accounting for losses of lense and voltage sag.

Try to get a proper 9v power supply.


The laser looks similar to this... 445nm 2000mW 2W Blue Laser Module Signal Outer Driver CNC Cutter Engraving TTL | eBay