Advice on part selection for 3w 808nm custom setup

[simplexorion]

Hey all,

Planning on building a laser for a relative. He is the expert enthusiast and I have a sense of what he is after. I found a member here to make a nice matte black host that he wanted. Need input on my diode, lens, driver heatsink setup.

I was thinking one of these diodes

3W-808nm-Laser-Diode-C-mount-with-FAC-lens/323721718452?hash=item4b5f516ab4:g:fwMAAOxyHE5Rn7T9

808nm-3W-C-Mount-Laser-Diode-CW-Semiconductor-Diode-TO3-Sealed

Oops I cannot post links as yet unfortunately. The two diodes were found on eBay though.

I am having trouble sourcing an appropriate driver and would like some input on part choices. The gift is for an enthusiast, so I'd like quality parts that have endurance for a well made piece.

Thanks in advance.

 

[Encap]

OK I give up? Sounds like a little kid with an overactive imagination imaging" burning" things with an invisible laser, who is an "accident looking for a place to happen". I could be wrong, however 808nm hand held lasers are very very seldomly ever asked about or desired here on LPF---99.9% of all the threads on LPF are about visible output lasers for obvious reasons--so is more than just unusual.
There are much better and much more powerful lasers for so called "burning" available than an 808nm.

Why does your uncle want or need a 2.5 to 3.5W 808nm invisible laser and that can't be seen and is very dangerous for eye safety reasons to anyone in the invisible beams path? For what reason or purpose assuming your enthusiast uncle is an adult who wants a laser made by someone whose " electrical knowledge is fuzzy", soldering skills minimal, and has no experience building lasers or what is needed for a high quality result using a C mount diode?


Why doesn't your " enthusiast" uncle already have one? They are not expensive and excellent professional quality 808nm hand held laser are available from Jetlasers among others for $199 to $299 See: https://www.jetlasers.org/index.php?id_category=18&controller=category

Whatever the case--excellent drivers, modules, , heat sinks,and lens assemblies can be purchased from member DTR- See: https://sites.google.com/site/dtrslasershop/home/laser-drivers

Best advice is have a member who knows what they are doing and has the experience, equipment, and skills necessary build a laser for you or get a commercially made JetLasers PL-E Pro they come in black or silver

 

[icecruncher]

usually when someone wants an 808nm is because it is cheaper for the actually laser diode. (about $30 - 35 for the diode) so, my guess is same, probably someone who isn't in the work force and has time on their hands. Although the NDB7A75 is only $50, and the NUBM08 is only $35 so who knows.

If I am wrong please let us know.
If you are building a laser, a C mount is not what to start with.
808nm is not what to start with either - it will show a glow from up close, but much harder to work with and more dangerous.

 

[simplexorion]

Hello again. Nothing irresponsible here. Uncle is a retired engineer and likes cool stuff like this. Wanted to give him something I'd made myself. I actually looked st Jet Lasers for inspiration.

Where my understanding has fallen short is one what is a gold choice in diode for this project. I bought my matte black host that supports two 1650 batts.

I know I need my diode, driver and lens now with a heatsink to match my host. I have a g2 lens. Just looking for solid advice on diode and a driver that goes with it. I am not clear on how the driver should be tailored to the diode and power etc.

Tia

 

[RA_pierce]

A G2 lens is a poor choice for the diode you intend to use.
First, the G2 is broadband coated for visible light, so you will not get optimal transmission at 808 nm.
Second, the G2 lens is a short focal length lens and the 3 W diode is a multimode or multi-emitter diode. This combination will give you a very large divergence angle. A long-focal length lens (~20 mm) with a large diameter (>10 mm) will be best suited to a diode like that to minimize divergence. No matter what you use, however, utility of the laser will be limited because of the poor beam characteristics, very low brightness to the unaided eye, and very high potential for injury.

If you do go forward with this project, it is HIGHLY ADVISED that you purchase safety eyewear appropriate for the 808 nm wavelength as this laser can be extremely hazardous to your (and your uncle's) vision.

As for a driver... check the data sheet for the diode you want to use. It will tell you what the operating parameters are for the diode. Likely it's somewhere around 2.5 V and 3.5 A input. A simple DIY linear current regulator will do but you can also purchase off-the-shelf drivers like this from shops on the internet.

Two Li-Ion batteries will supply much higher voltage than this diode requires. If you use a linear regulator, the extra energy will be wasted as heat, which is not a good thing. 808 nm laser diodes have low operating voltage relative to many visible diodes used commonly. It's best to use a battery and driver configuration that maximizes efficiency of the whole system. In this case, a buck driver capable of high current (~3.5 A) or a linear regulator and a low voltage battery that doesn't greatly exceed the forward voltage of the diode.

I suggest you do much more research before you begin.

 

[gazer101]

Hello again. Nothing irresponsible here. Uncle is a retired engineer and likes cool stuff like this. Wanted to give him something I'd made myself. I actually looked st Jet Lasers for inspiration.

Where my understanding has fallen short is one what is a gold choice in diode for this project. I bought my matte black host that supports two 1650 batts.

I know I need my diode, driver and lens now with a heatsink to match my host. I have a g2 lens. Just looking for solid advice on diode and a driver that goes with it. I am not clear on how the driver should be tailored to the diode and power etc.

Tia

Make sure to give him a pair of camera-vr goggles with that too, so he can see the beam (CMOS sensors can see 808nm)