why are there no strong 532nm diodes?

[Mannitu78]

Hello men,
i was just shopping around on Ali Express and realized that there literally are no strong 532nm diodes. I remember years ago when somebody explained me the first time a few things about green lasers, that the 532nm DPSS diodes(or modules) are cheaper than the "real" green diodes. Makes sense, why else would you go through that process of adding extra parts, if it wasnt cheaper. Now the 520nm diodes are not that crazy expensive actually, whats more surprising to me is that i cant find any 500mw or 1W+ DPSS diodes/modules. The 1064nm IR diodes on the other hand are dirtcheap, so how come that there are no strong 532nm DPSS modules around? I actually like the 532nm colour much more than the "real" green diodes.

 

[ZRaffleticket]

There aren't strong 532nm diodes specifically because 520nm is better for color mixing -- the intent behind their mass production.

As for 532nm DPSS, it's just the nature of the technology. Most of them come from a more complicated process than directly doubling a 1064nm diode (for various reasons, but bottom line is that directly doubling a diode is much harder than directly doubling a YAG line). Your typical 532nm DPSS sources convert 808nm -> 1064nm -> 532nm. Each step is not 100% efficient -- alignment (rotation included) plays a large factor in this, so do coatings to reflect and transmit the right wavelengths, and so does temperature. Bear this in mind when you consider: to get higher power out, you need higher power in. As power goes up, so does waste heat. The crystals which do the conversion are temperature sensitive, more heat means less efficiency. Additionally, the simpler optical assemblies which are a straight line of [diode-yag-doubler-coupler] are not going to convert as well as other more physically large assemblies that you see in higher power lab setups, which take better advantage of efficiency and have room for cooling.

 

[Sowee7]

i feel like this is a troll

 

[ZRaffleticket]

Even if it is, the thread is probably going to get indexed on search engines. IMO better to have the info accessible.

 

[Mannitu78]

@Sowee7:
if you think this is a troll you really got issues man. Is that your philosophy, anybody asking a question you already know the answer for is a troll? Because everything you know is essential and people must know and everything YOU dont know isnt important, right? Maybe in your world adult people have the time to come up with troll questions.

@the ZRaffleticket:
so whats the conclusion for me now when i want a strong 532nm laser? Would i have to build that on my own, buy a crystal and a IR diode? I guess thats more expensive than a 520nm diode. Im just wondering why people are saying that DPSS Lasers(fake green lasers some call them) are cheaper. If thats true, it only seems to be valid for the weak ones.

 

[ZRaffleticket]

For strong 532nm, look for a lab laser on ebay. If you want it portable look into what jetlasers offers.

A bit less advised, but an option is to buy a bare module + IR filter (CNI, lasever) and find a way to make your own host for it. I really don't advise doing anything more custom since DPSS is very finicky, not to mention dangerous being made with high powered lasers you can't see. It will take a while to get anything to work, and when you do there won't be much to show.

But yeah I would tend to agree with your sentiment, 532nm is really starting to only be cheaper for low end crap anymore.

 

[Sowee7]

@Sowee7:
if you think this is a troll you really got issues man. Is that your philosophy, anybody asking a question you already know the answer for is a troll? Because everything you know is essential and people must know and everything YOU dont know isnt important, right? Maybe in your world adult people have the time to come up with troll questions.

@the ZRaffleticket:
so whats the conclusion for me now when i want a strong 532nm laser? Would i have to build that on my own, buy a crystal and a IR diode? I guess thats more expensive than a 520nm diode. Im just wondering why people are saying that DPSS Lasers(fake green lasers some call them) are cheaper. If thats true, it only seems to be valid for the weak ones.

its because you kept on calling 532nm dpss lasers, "fake diodes". they are using a totally different process than diodes. they are not fake lasers, they are very real and have better specs than diodes (usually)

 

[Mannitu78]

i bought a 100mw green laser in the "gatlinggun" host from China für 19eu Once. Looks like 100-200mw is the limit on what you can get them. I guess taking one apart and changing only the IR diode for a stronger one also isnt an option? I guess that crystal would break down with the higher input power? Or maybe last at least a few hours?

Well the title should have been "532nm modules" and not "diodes", it is, however an expression mistake(an obvious one imho)and not a troll.

 

[ZRaffleticket]

Short answer, no it is not an option. It's not that easy.

I'm not saying it can't be done, but there are too many factors that make it too impractical to try doing. If you swap the diode you'll also need to swap the driver and realign the system. Potentially will need more optics to shape the new IR input. Modifying one can be even more limiting than building from scratch since you're confined to the original space. The alignment itself is the first issue, followed shortly by thermals. It is not beginner friendly by any means. I think most members here - including veterans - would struggle to get any green light out at all. You wouldn't be worrying about anything breaking down, you'd be wondering why you aren't seeing any green. To make it more powerful than what it started at is optimistic to say the least. You'd also need to be playing around with IR, meaning you'd need the equipment to see the beam shape so that you can adjust the optics, and protective goggles of course.

The higher power modules (400mW+) are more expensive because of the engineering they need to get working. They always have been this expensive. Even higher power green diodes have just gotten cheaper.

 

[RedCowboy]

Do you have a link to any better than the Sharp GH0521DE2G at a good price ?

 

[Mannitu78]

72.3US $ |NICHIA NUGM04 / NUGM04T TO5 9mm Grün 525nm 520nm 1,6 W Laser Diode für DIY Laser Module|Bühnen-Lichteffekt| - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

de.aliexpress.com

ill go for the biggest one then...after i finished my blue laser. I consider 83eu to be cheap..at least if you look what prebuild 1,6W green lasers cost..or even 1W.Edit wow just realizing you guys in US even get better price from Ali in this case.

and heres a 500mw from sharp not that expensive at all:

44.64US $ |Sharp GH05C01A9G 520nm 500mW ZU 5 9mm Grün Laser Diode|Dioden| - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

de.aliexpress.com

and here a 600mw diode for very reasonable price. This seems to be one of the best shops by the way (Shop5781513 Store)

36.19US $ |Sharp GH05C01A9G φ9mm Grün 520nm 600mw Laser Diode (Puls 1W)|Bühnen-Lichteffekt| - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

de.aliexpress.com

by the way, its offtopic, but do you guys have any experience with these "modded" diodes or whatever you call it? They are triple the usual price but claim way better beam. Or better said, they claim smaller spot for cutting purpose. I have no idea how the beam works out on longer range.

 

[RedCowboy]

I was looking for a single mode green better than the Sharp GH0521DE2G since we were talking about dpss, granted the direct single modes produce a slightly rectangular beam rather than a Gaussian beam like a dpss operating in TEM00 but they are quite good.

Both that 500mw and 600mw 520 are the same direct multi mode diode, they can be overdriven so different sellers will list different output numbers, but it's the same diode.

That last one is a FAC fiber enhanced multi mode only they appear to have added an adj. lens for cnc, they work well for home CNC but you can also get a tight far field spot with a wider longer focal length lens set a few inches out.

The single modes are not as strong as the multi modes but the divergence is much better if you like a nice thin beam with a tight spot, the multi modes produce a bar/line in the far field without additional corrective optics due to the aggressive fast axis.

Here's one of those FAC enhanced diodes without that added shroud/lens > FAC blue

 

[Mannitu78]

i see. So that 135mw singlemode diode you listed can not be "overdriven"? What will happen if you put 20 or 30% extra current through it?
So do this FAC diodes also help you, when you want to max out the distance while still maintaining a small spot? Would you be able to ignite things on a further distance, if you combine them with the G8 lens? More distance than just a regular diode+G8 lens?

 

[RedCowboy]

The Sharp 135 can be overdriven to do about 225mw. Overdriving can shorten MTTF

The FAC ( fast axis correction ) added to the multi modes are often used for home CNC ( with a small lens such as G8, G2 ) but you can use a wider longer FL lens to burn further away, no primary ( G8 ) or other lens is needed in that case, just a bigger lens to focus down from a wider starting point further from the diode to a tight far field spot.

 

[Mannitu78]

im interested in bringing it in a small form-factor Casing with 2x16340. Im not sure what youre reffering to, when you say "but you can use a wider longer FL" but i feel like its not compatible with my idea of my casing XD.
So if you want to achieve a burning point on long distance, all in a "regular" case/modul, FAC diode + G8 lens would be the way to go?

i just bought this diode

36.64US $ |NICHIA NUBM0E Recapped φ9mm Blau 455nm 450nm 5,5 W 6,5 W Laser Diode LD|Bühnen-Lichteffekt| - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

de.aliexpress.com

also an IR diode and a bunch of drivers to experiment with, cant wait for that cool s...t to come yeeeehaXD

 

[RedCowboy]

No, you would need a wider lens of 40-50mm wide or more to get any decent reach ( 10 meters )
If you want to keep it compact you can use a G8 and attach a beam expander for reaching out a little, better would be to use corrective optics in your build but that's an advanced build and 2 x 16340 are going to be working hard to power the NUBM0E but they can, just not for very long before needing to be recharged. You can usually fit 2 x 18350 in the same flashlight tubes as 2 x 16340.

The first two numbers are the battery width 16340 is 16mm wide and 34.0mm long.
18350 is 18mm wide and 35.0mm long.

Remember to wear your laser safety glasses when appropriate and lase safely. Be extra careful with NIR so as not to blind yourself.