Where to get cheap high power uv laser diodes

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1

I see they have 200mw 405nm laser diode modules, on eBay that go for around $70. I also see ones claiming "2.5w" at 443nm lasers. Those modules include housings, power supplies, and optics - which I do not need. I can make my own housing and power supply, I was just interested in buying the diode component itself. So I looked around and haven't found anything obvious. I was expecting to buy the diodes in 10 packs or something somewhere, but I having trouble searching.

Does anyone know where to buy cheap, high output laser diodes ?

2

Uh, have you tried ebay?

It doesn't appear you have - I get dozens of results searching for 443nm laser diode and 405nm laser diode...

Note that a bare diode does not include a lens, which is necessary to focus the light into a beam like you traditionally associate with lasers. That's why most of the ebay listings are for modules, not the bare component.

3

Well, when I posted initially, I must have got saturated and couldn't find anything for quite a whole. Now I'm back on and finding the diodes for like $10-$20, from all types of shady sellers.

I was hoping to get some input from anyone who has experimented with this type of stuff too. I had a few diodes that worked cutting black electric tape. But I got frustrated figuring out how to focus the lens, and put them away. I figured out now I can use cell phone camera on taped to a hat. It doubles up as protective eyewear too.

I figured, I would buy a bunch all the same and try over driving them, changing the cooling and control - to find the sweet spot. But unfortunately, the diodes for sale aren't consistent in any way - and is like buying 5 different ones which could be used from who knows where.

4

DocStein99:
But unfortunately, the diodes for sale aren't consistent in any way - and is like buying 5 different ones which could be used from who knows where.

That's price we have to pay for the cheap one. They almost produces in China, maybe a fake or noname one and the quality is not consistent at all. Should never use in the critical project.

5

Well... at $10 each, is almost like a pricey drill bit. So I won't go broke using them, but a little more careful then the resistors that fall on the floor that I'm too lazy to pick up.

6

You have to watch out with power ratings for frequency-multiplied semiconductor lasers - you
may see the IR power quoted (ie before the freq-multiplier crystal), rather than the output
power at the target wavelength (blue are often freq tripled and thus rather inefficient). Of course
if its a direct blue laser there is only one optical power rating.

7

upj11097:
That's price we have to pay for the cheap one. They almost produces in China, maybe a fake or noname one and the quality is not consistent at all. Should never use in the critical project.

Actually it is the price of not dealing with a reputable distributor. A few years ago one of my customers spent an entire year trying to get green laser diodes that would work for a commercial product. And they were paying high prices. The Ebay pieces are always drop-outs.

Paul

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I suspected eBay cheap products were probably factory defects or otherwise. I know if I buy a MOLEX connector from MOUSER, it's guaranteed & certified. But cheap eBay devices, I will accept for my research and learning purposes, since I just can't afford to burn up $100 diodes for demonstrations.

Paul_KD7HB: I am trying to learn. I won't buy anything I can't afford to break, throw away, and then pull another one out of a pack of 5+.

MarkT: Are you telling me the diodes have stamps on them ? I never looked. Some of the sellers give product numbers, for me to lookup a datasheet filled with information I know little about, and mostly gives me a headache after attempting to read 2 pages with symbols for scales I have never heard of before.

The cheap laser diodes are for me to build a laser cnc stage to vaporize a paint layer from the top of a copper clad fiberboard, to raster the pattern for PCB etching. So if a 405nm laser or 443nm laser is not the least expensive and most powerful one to get that job done - I am really interested to entertain suggestions.

Obviously a commercial CO2 laser system will do that, and probably even vaporize the copper layer itself - I just can't afford that, and do not have the means to build a CO2 laser, ruby, or other complicated laser. So I will start with least expensive laser diodes, possibly combine 2 or 3 beams of the highest output focused to a single beam, and upscale from there until I get my result.

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I just found a 100w pulsed fiber laser, whole setup with the lens and everything for $9.00. Really? How is this even possible.

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Its a misprint.

£9000 i would believe.

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I figured, I would buy a bunch all the same and try over driving them, changing the cooling and control - to find the sweet spot. But unfortunately, the diodes for sale aren't consistent in any way - and is like buying 5 different ones which could be used from who knows where.

To some extent that's normal. Laser diodes are very non-linear and "unstable".

Have you researched laser power supplies? I've never built a laser power supply, but laser diode power supplies are tricky and you have to use optical-output feedback to keep the light output under control. (You may also need temperature feedback.) Does your power supply have optical-power feedback to hold the light-output constant?

12

I will use a constant current driver. It looks like nothing more than a sensitive LED diode. I could put a thermo-couple on the heat sink near the diode, I'm sure that would help me figure out how much heat is too much heat.

If your talking about a professional rack mounted fibre laser power supply, then no - I do not have that.

Last night my laser printer decided to stop working. It might have needed a new toner cartridge since it's really light, but I wasn't buying another one of those for $150. I'm tired of manually feeding 1 sheet at a time for them to get stuck inside. So I took the whole thing apart to find a nice wonderful octogon optical reflection mirror mounted on a motor, with pretty much everything I need to raster a repeating y-pattern down to an motorized x-axis linear table.

Ironically, the laser diode inside of that looks just like the uv laser diodes for sale on ebay. I'm shocked (just kidding). Anyway. There is no heat sink. So I might play around with this until I burn out the stock laser diode, and then figure out a way to bounce the light off the sinked uv diode through this nice mechanism.

13

DocStein99:
So I took the whole thing apart to find a nice wonderful octogon optical reflection mirror mounted on a motor, with pretty much everything I need to raster a repeating y-pattern down to an motorized x-axis linear table.

If you are hoping to expose PCB with that , dont waste your time

It will not work as you might expect.

14

405 - 423 nm are not really UV.
Freq tripled IR to get near UV?? what a load of horse hockey......

If you want "High powered" 405nm diodes, check out DTR's Laser Shop (DTR's Laser Shop). very reputable dealer, see LaserPointerForum.com.
You are not going to see any 1W+ 405's offered in '10 packs'. expect to spend at least $25.00 for 1W's and at least $40-50 for the 2.5Watters. At those powers, you really should consider the copper modules with GLASS lenses (the acrylic ones will scar and burn at those powers).
Stay away from the IR's, the diodes are cheap, the collimating lenses are expensive ZnSe, and bad for your eyes....

Most of what you'll read on this forum about LASERs is uninformed bull. Spend some time on the LaserPointerForum. You'll get better, more accurate, information from folks who have actually built and used LASERs (diode and Gas).

15

If this is purely for PCB.

I used to have a pen plotter which was basically a thin tube (no optics) coupled by a fibre optic to a UV light source, no lasers involved.

Worked fairly well , although it was only used for through hole on 0.1 spacing.

123Splat:
Freq tripled IR to get near UV?? what a load of horse hockey......

Pumped lasers that do this exist.
Not for $70 though.

DocStein99:

The cheap laser diodes are for me to build a laser cnc stage to vaporize a paint layer from the top of a copper clad fiberboard

I would suggest that this is not very practical.

Vaporising paint gives off smoke which will rapidly damage the optics even with 50W CO2 gas lasers.

Do you have any links to something you have seen on the net ?
There is a lot of hogwash out there.

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123Splat: I can relate to that, there is no shortage of other people out there trying to cut & melt with cheap or recycled parts. Thank you for the link for me to explore. I would actually need a separate room in my house filled with optical tools in order to build a big-boy laser myself.

Boardburner2: A simple fan can remove the gas and smoke away from the surface of a burning surface, I don't know why I see so many demonstrations and that's not done. It would take some control between vacuuming the smoke just enough so it does not cool the surface thats trying to be burnt.

I know how a good CO2 machine is made, and it takes a large space to house the power supply, and maintenance is also needed for the mirrors that must be calibrated. I am not exploring a CO2 option, to buy or build, that project is outside of my tooling means and exceeds my budget.

I am interested in knowing more about the fibre coupled uv light source. I am confused. How would photo-emulsion activate WITHOUT a light source? Are you saying I can just use a simple uv diode though the fibre, instead of a laser diode ?

Here are some successful inspirational links:

Laser rastorize PCB using cheap diode and linuxcnc spinning joint

2 laser diodes focused to 1 beam

My favorite: 900 ma laser diode 453nm burns a visible pattern

I have some more examples and links I can give, I can't find right now and can post them as I find them again. From the 3 I posted, you can get an idea what I'm looking to do from those examples. Yes, there could be some "SMOKE AND MIRROR" trickery, of course. But none of us can dismiss, a cheap burning laser diode is strong enough to cut electric tape, burn wood, and melt black plastic.

I feel with enough trial and error in different substrates, acrylic, latex, enamel, etc... There are so many untested chemistries of paint, glue, emulsion, wax.... So instead of building a more powerful expensive laser, I will be just testing the reaction to different coatings on the copper.

HEAT and ambient room temperature effect the power on burning lasers. Everything has a flash point, and if it's just heated below flash when laser hits will cause a reaction, just the same way the X & Y axis uv-curing lasers work on the additive 3d printing in submersed liquid uv curing epoxy.

17

No smoke and mirrors... a 30mW (Optical Power output), or so, red can burn through black vinyl electrical tape. takes a few seconds, but does the trick. A (relatively) cheap green DPSS pointer, at an honest 30mW optical output, will cut the tape like the proverbial 'hot knife through butter' (because it uses close to a Watt of IR (with a lot of leakage) to generate the 30mW green). the key parameter is optical power, not electrical dissipation, and the characteristics of the material being cut/burnt/engraved...

Ambient tempreture and any 'cooling' of the target is not really that much of an issue. the beam's energy is delivered to a point on the surface being graved. there is no reliance on retained heat energy (that is why you get a nice little charred dot of a hole when burning through a material, instead of a flaming mass, assuming a well collimated beam). as the target's surface is ablated away by the beam, a new surface is presented and ablated. the combustion byproducts are removed by positive airflow across the target (as in your 'big boy' CO2 LASERs. If it works with the gas LASER's (and it does) it will also work with Diode LASERS (and, it also does).

As for DPSS Blues,,, I have never seen or heard of any. That by itself does not mean that they don't exist,,, BUT, If they are so expensive, and considering: 1) pump power required per output power, and 2) the power limitation posed by the fragility of the doped SS crystals required,,, why would anyone want to use one (if they, in fact, exist) when you can acquire a solid state diode LASER that can produce much more optical power for much less money, at the same wavelength???

18

What I mean about the cooling is how the temperature effects the reaction between the electrical tape (or whatever I'm trying to vaporize) and the beam. Just like you say, the surrounding area is a charred hole - that char reacts differently to the beam, than fresh new pvc (or vynil or whatever tape is made of). If the power & speed is controlled and I don't make a crater, then possibly the surrounding material gets hot and melts, warps or whatever.

So just a thin layer of a delicate material to vaporize. A wax, water based ink or paint of some type. Something that won't turn into a charcoal crater and make hills and valley's near where the beam reacts to the area.

19

You use a air flow directed at the target spot. That will not remove enough heat to significantly decrease the heat energy delivered to the target (heat is created/released when the photons hit the target. the beam itself is not hot until it interacts with some medium.). The air flow removes debris from the ablation area (mostly gasses, as the ablation is vaporization of the target material. LASER Lense damage occurs from two sources: 1) heat generated by electrical dissipation and photon reaction with the lense material (that's why you only use acrylic lenses with LASER diodes delivering less than about 1/2 Watt)), and, 2) condensation of ablation gasses on the lense exterior being cooked on by the heat. the air flow takes care of the later.

There are lots of guys burning paint off treated pcb's to create etch patterns. using diode to burn the copper off is quite another story....

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I am not trying to burn the copper off. I just want to burn a layor of paint.

A little fan at a 90 degree angle to the work area should do it for me. Or a vaccume line, maybe.

I received my super cheap "200mw" laser diode module in the mail. For as cheap as it is, I am impressed with how much I got. A nice PWN current driver board, with a pot to adjust something - who knows what, since the documents did not explain. 12v in, and 2 wires for a 5v common pwm signal.

The metal housing is suspiciously heavy. I was expecting some cheap lightweight hollowed out something, but it actually feels as if it were made of steel. I forgot to do a magnet check, I will figure out what that shell is made of and why so heavy.

I haven't dismantled the head yet, however the document claims there is a glass lens installed. Once I unboxed the unit, connected to my Arduino PWM circuit the laser head was out of focus. I focused the beam and was able to create smoke from a piece of black rubber - to test make sure unit works. Ok done - I boxed it back up and waiting patiently for my knock off laser goggles to arrive.

Unfortunately I don't have a laser lab or know where one is to gauge and certify these laser goggles are actually safe to use. I was planning to put everything in a cardboard box, with a camera. laser aimed at the glasses, and use the camera to see if / how much laser light goes past the lens of the glasses. I am guessing it will let some light through, but I have no way to know how much light passes and if it is hazardous.

Considering a pair of certified laser glasses cost like $100+, I figure it might be cheaper and easier for me to use this old welding facemask with phone camera taped to the front. It's bulky, but safe.