4W C-mount 808nm IR laser

[Pman]

Figured I would post it although it isn't something a "normal" laser member would build. Basically I built it because I wanted to try my hand at a c-mount diode and I've had the diode for awhile. This is kind of an informational build post to show how it is put together.
Here's the c-mount parts that came from an Ebay seller from China. Just put in c-mount and you will find a few different styles:

3W Diode mounted:

Insulated negative wire to mount through the hole:

Cruddy pic that shows the wire up through the hole and then soldered to the ribbon:

Put down some Arctic Alumina as a just in case:

Here's the other piece and they will press fit:

Pressed tight:

Here's the front piece screwed into it but I didn't end up using it because you lose most of your power with the IR spread:

With the + wire attached:

I could have sworn I had taken other pics with the 5W driver mounted in to the Kryton Groove host but I couldn't find them so after testing I ended up with 4W of 808nm using an Eitan lens. I haven't figured out how to make it focus regardless of what lens I use and farther out like a few inches so basically the closer you put something black to the laser, the more it burns. Nothing to really show for that though so here's the completed unit:

Yup, kind of boring but at least I know it's pretty easy to build a c-mount. I will say that this morning when I was messing with it I accidentally left it on for probably close to 10 minutes and the whole host was really warm almost hot. Considering there really isn't much heat-sinking I was impressed that the diode took it.

Here's a teaser pic of this build with the other builds I haven't shown yet to make up for no IR beam shots:

 

[diachi]

Nice build! good to see we have easy access to mounts for C-mount diodes now - I remember that being a problem previously, back in the early years of the Kryton host - there was much talk of designing one specifically for C-mount diodes.

 

[CurtisOliver]

Nice informative post Don't hear much of C-Mounts anymore.

Nice build! good to see we have easy access to mounts for C-mount diodes now - I remember that being a problem previously, back in the early years of the Kryton host - there was much talk of designing one specifically for C-mount diodes.

Just need hosts that can take the heat now.

 

[diachi]

Nice informative post Don't hear much of C-Mounts anymore.
Just need hosts that can take the heat now.

The nice thing about IR diodes at least is that they are usually somewhat more efficient than visible diode lasers. But yes, some bigger hosts would be good - need another customer machinist to start machining!

 

[CurtisOliver]

IR diodes are very efficient compared to visibles. The lasing medium is more optimised for IR wavelengths. Bigger hosts with larger heatsinks, would be much appreciated for some.

 

[diachi]

IR diodes are very efficient compared to visibles. The lasing medium is more optimised for IR wavelengths. Bigger hosts with larger heatsinks, would be much appreciated for some.

Up to 60% electrical->optical efficiency for some IR diodes. I'd imagine closer to 50% for these diodes - which is still a ~20% improvement above an M140 or some such and an even better improvement over green diodes.

I'm just going to avoid the issues of heatsinks being too small and build lab units once I have the spare cash... :wave:

 

[CurtisOliver]

Labs are the way to go. More stability, generally a better output due to cooling. Not having to rely on batteries. You get more out of a laser in lab form. Just portables are easier to transport funny enough.

 

[BowtieGuy]

Nice build Pete, good tutorial on those C-mounts! :beer:
It's kind of strange, that both of us haven't posted a build in a long while, but we both post a build within a few minutes of each other!

 

[diachi]

Labs are the way to go. More stability, generally a better output due to cooling. Not having to rely on batteries. You get more out of a laser in lab form. Just portables are easier to transport funny enough.

Oh yeah, don't get me wrong, I'd like more portables too. But there's more experimenting that can be done with lab units.

Anyway ... going to end up derailing this thread so I'll shhh for now. :shhh:

 

[CurtisOliver]

Nice build Pete, good tutorial on those C-mounts! :beer:
It's kind of strange, that both of us haven't posted a build in a long while, but we both post a build within a few minutes of each other!

Spooky
Yes, I'll stop derailing the thread too.

 

[Pman]

Yeah Jeff, I noticed you post yours immediately after I put mine up. Got to go see Bows minty green if you haven't. Awesome looking build. Kills me that some of you guys can just machine a heat sink. If I had the stuff and could do it it would be scary the kind of stuff I would come up with
I still have all those other in that last pic I threw up to post. Just thought I would show something a bit different this time. You can see the 2 raelly heavy Brass double 18650 builds there. It was hard making a decision on what to put into them as they needed 9mm diodes. Came up with a good answer for it I think considering brass isn't the greatest heat-sink material.

 

[Lifetime17]

Hi Pman,
Now that is a great thread C mounts made easy you planted a seed now I'm going have to do this Awesome buddy. Great pics step by step..+ Rep if i can ,And yes i can Woo Hoo !!!

Rich

 

[Pman]

Thanks. I think the 1W 650nm are $100.
This is the 3W 808nm one I had:
Electronics, Cars, Fashion, Collectibles, Coupons and More | eBay

 

[icecruncher]

I follow the build, nice pics and so forth.

But,,,, How does that eBay c-Mount get mounted in the Krypton? That is where i got lost

Does it replace the head on the kryton or is there something else I'm missing.

 

[Pman]

I understand Ice. I thought I had taken a couple pics of what I did but apparently not. I'll have to see if there's anything else I can show with it.

The top silver piece doesn't do anything and can be popped out as it has a gasket that keeps it in place. The ringed piece has the lens attached and can turn to focus although like I saI'd it doesn't really focus much other than really close. The c-mount/ heat-sink assembly is pressed into the host and there's a plastic hollow spacer where the wires go down the middle to the contact board and it's wired case -. The hollow tube is cut the correct length to keep the right tension against the contact board so it stays hard against the lip inside the host and won't lose connection when the batteries are installed. Hope you understand.

 

[RedCowboy]

Good build Pman.

I have changed some 808nm c-mounts in my older green lightshows and they make sense to be built that way, they give a good heat transfer for a 1 screw attachment.

Also I like that many of the 808's come with a tiny FAC at the emitter, using a security type camera I can see the output and get a good focal point out in the yard, they have burning potential but no pretty beam and as you know must be handled with great care as that invisible light is focused by our eye onto our retina.

One more thing the C-mount has going for it is it's compact size, an array of several could be built into a reasonably small area.