Lasers from China

I pulled out some 10mW green laser modules from some weapon mounted lasers.  I notice that they solder the board directly to the laser pins.  I'm just curious if these laser diodes are similar to the diodes we pull from our DVD burners.. such as having one side for laser and the other side for reading.  

I was thinking of taking the module and replacing it with a different diode.  Apparently 2 pins are connected together.  Currently I'm assuming the 2 connected together are the ground and the detector.

If it is a Green Laser as you say... the Laser Diode will be an 808nm...
pumping crystals to produce the 532nm green...
You can't replace just the LD...  


Jerry

What do you mean you can't just replace the diode?

Oh.. and for clarification, I was considering using a IR diode as a replacement. Technically I actually have a few modules that were meant for green laser diodes, but they haven't been populated with diodes yet. Since I don't have green diodes, I wanted to see if I can do a IR diode.. My target power of the IR laser would be 10 mW..
I suspect the power level of the green diodes would blast a IR diode from a DVD burner up to a burner level way above my 10mW target. I think I read somewhere that to get a green laser you needed 300 mA and I believe that relates to 180mW of IR power.

The pinout of the IR diode is different from red laser diodes, but wasn't sure about green laser diodes. That's why I was asking about pins being shorted together..

Ryo said:

What do you mean you can't just replace the diode?
Oh.. and for clarification, I was considering using a IR diode as a replacement.  Technically I actually have a few modules that were meant for green laser diodes, but they haven't been populated with diodes yet.  Since I don't have green diodes, I wanted to see if I can do a IR diode.. My target power of the IR laser would be 10 mW..
I suspect the power level of the green diodes would blast a IR diode from a DVD burner up to a burner level way above my 10mW target.  I think I read somewhere that to get a green laser you needed 300 mA and I believe that relates to 180mW of IR power.
The pinout of the IR diode is different from red laser diodes, but wasn't sure about green laser diodes.  That's why I was asking about pins being shorted together..

Click to expand...

You need to read much more. You are mixing terms and ideas so much that you are virtually unintelligible. For example; green laser modules do NOT have a green diode in them.

Peace,
dave

For reference, here's the typical layout of any small green laser module like yours:

>200mW 808nm laser diode (IR) => pump focusing lens => Nd:YVO[sub]4[/sub] crystal => KTP frequency douling crystal => output coupling optics (collimating lens) => 532nm green output.

The 808nm IR diode (MUST be 808nm) pumps the Nd:YVO[sub]4[/sub] crystal which gives us 1064nm light, the output of which is fed through a KTP crystal which frequency doubles the 1064nm light into 532nm green light. This is currently the only way to produce this color of green light in a small module for pointers, gun sights, etc.. There is no such thing as a green laser diode.

As you can tell, green lasers are always MUCH more complex than any laser diode by itself. In order to replace the diode in one of those modules, you'd need at least a 200mW 808nm diode.

If you just wanted to convert the module into an IR only module, the optics that are built into these green modules won't work properly. The only way to make an IR only module with parts from a green laser module is to remove the IR diode from the green module and press it into an Aixiz module, and then power it with the driver of your choice (you can use the tiny driver that was attached to the green module..).

Ryo said:

What do you mean you can't just replace the diode?

Oh.. and for clarification, I was considering using a IR diode as a replacement.  Technically I actually have a few modules that were meant for green laser diodes, but they haven't been populated with diodes yet.  Since I don't have [highlight]green diodes[/highlight], I wanted to see if I can do a IR diode.. My target power of the IR laser would be 10 mW..
I suspect the power level of the [highlight]green diodes[/highlight] would blast a IR diode from a DVD burner up to a burner level way above my 10mW target.  I think I read somewhere that to get a green laser you needed 300 mA and I believe that relates to 180mW of IR power.

The pinout of the IR diode is different from red laser diodes, but wasn't sure about [highlight]green laser diodes[/highlight].  That's why I was asking about pins being shorted together..

Click to expand...

Hey Ryo...
you have posted 111 times on the forum and you have been registered
for 204 days...
You could not possibly have been doing too much reading or research on the forum if you
still think that Green Laser Diodes even exist... :-/

A small suggestion.... perhaps you should do a little more reading... :-? :-? :-?

Jerry

Okay.. I'm getting hit by the green laser is not a green laser.  yes I know it's a IR diode.. haven't read the details about that.  That actually wasn't my concern about making a green laser since I have a green laser, I was thinking of making a IR laser using the driver circuit that came with the green laser.

The whole point about the question was to talk about the driver circuit..  the 2 pins of the "green" laser diode is connected together to ground on the circuit board.. so didn't know if I solder a replacement diode (with the correct polarity) would I have a problem. Note I've seen this design on a few modules on lasers I have opened up..

As for the posting of 111 times in 204 days.. I disappeared for a while.  Been busy with other projects and jobs.  I have 2 jobs and a baby.. so I rarely have time to do a lot of stuff.
I've also already build up 2 lasers, 1 BluRay and 1 Open Can burner.. and have a BSEE degree (so I understand circuits).  But of course i'm always trying to learn more.   Great stuff here on this web site!  

As long as you replace the diode with another 808nm diode, then the connections will stay the same..

Ryo said:

Okay.. I'm getting hit by the green laser is not a green laser.  yes I know it's a IR diode.. haven't read the details about that.  That actually wasn't my concern about making a green laser since I have a green laser, I was thinking of making a IR laser using the driver circuit that came with the green laser.

The whole point about the question was to talk about the driver circuit..  the 2 pins of the "green" laser diode is connected together to ground on the circuit board.. so didn't know if I solder a replacement diode (with the correct polarity) would I have a problem. Note I've seen this design on a few modules on lasers I have opened up..

As for the posting of 111 times in 204 days.. I disappeared for a while.  Been busy with other projects and jobs.  I have 2 jobs and a baby.. so I rarely have time to do a lot of stuff.
I've also already build up 2 lasers, 1 BluRay and 1 Open Can burner.. and have a BSEE degree (so I understand circuits).  But of course i'm always trying to learn more.   Great stuff here on this web site!  

Click to expand...

Sorry if I offended you about the length of time here... your previous post (green diode) just
seemed a little odd... :

If you want to build an IR laser... Take an IR Laser Diode and the Driver from your 532nm Laser
and mount them into an Aixiz Module... the Aixiz modules come with an adjustable lens.. so you
can focus the laser's beam..
That would be the easiest and fastest way... IMO..

Jerry

Oh I don't take offense that easily. Text is hard to read emotions..

Anycase that's what I was planning on doing.. IR Laser Diode in the driver.. but I'm trying to figure out if the short on the driver for 2 of the ground pins are going to be a problem if I solder all 3 pins from my IR diode. I wouldn't think it would effect anything, but just wanted to ask.

Only thing I can think of is that I need to make sure the ground of the body of the laser is isolated from the body of the IR laser since the case is + polarity. Weird they would do that..

The two pins that are shorted are case positive and photodiode.. the photodiode pin is shorted to case since the photodiode isn't used, and might not even exist in the diode in your laser.. The third pin is the negative pin for the diode.

In most green laser pointers, the case of the body itself is also positive.. You shouldn't need to isolate anything... I'm not sure about weapon sights, but I'd think it would be similar..

That's what I was thinking.. photodiode shorted to ground. Just didn't know what diodes they used in these Chinese units. Well I'll give it a shot after I adjust the power level down with my load diodes..

Hmm that leads me to a new question. Now many diodes do I need to simulate a IR diode from a DVD player?

I'd use 3 for IR diodes..

Thanks.