Choose a 405nm 120-200mW laser module?

[Leodahsan]

Well, in your context, single-mode = easier to focus and have a small DOT, but lower maximum power.

If you are really interested, read here.

If you are not limited in space, you can just focus the laser and make it closer to the "target". It will make things easier and cheaper.

 

[Sultanen]

Well, in your context, single-mode = easier to focus and have a small DOT, but lower maximum power.

If you are really interested, read here.

If you are not limited in space, you can just focus the laser and make it closer to the "target". It will make things easier and cheaper.

Okey, no, space is not to much of a problem for me, a "regular" laser it is then. Do you think a SF-AW210 would be a good choice?

For a lens i got an advice in my other thread of a Plano-Convex lens, i found those:
http://www.edmundoptics.com/optics/...ageNum=4&Sort=displayOrder&Order=asc#products
With a SF-AW210 and a Plano-Convex with a focal length of 300mm i would be good to go then?

Would this driver work for a 405nm laser diode?
http://www.o-like.com/index.php?main_page=product_info&cPath=65&products_id=15
I cant see why it would work for some wavelenghts but not for others, can someone explain?

 

[Leodahsan]

Okey, no, space is not to much of a problem for me, a "regular" laser it is then. Do you think a SF-AW210 would be a good choice?

For a lens i got an advice in my other thread of a Plano-Convex lens, i found those:
http://www.edmundoptics.com/optics/...ageNum=4&Sort=displayOrder&Order=asc#products
With a SF-AW210 and a Plano-Convex with a focal length of 300mm i would be good to go then?

Would this driver work for a 405nm laser diode?
2 pack Red laser/808nm laser diode driver 80-500mA w/TTL [OLDD20] - $5.99 : Zen Cart!, The Art of E-commerce
I cant see why it would work for some wavelenghts but not for others, can someone explain?

Dunno about the lens. I thought you just wanted to focus the laser and burn something.

Lemme know, your laser will reflect @ 2 galvo mirrors, and focus after that? I don't really get it yet...

Regarding the 6x diode
The SF-AW210 should do, but all depends - output power, how you can dispense heat... you want your diode to live 5000 hours?

Regarding the driver
Commonly, the 405nm laser diodes operate at a higher voltage (around 6v) so those drivers are "boost mode" drivers, so you can insert a single li-ion battery (3~4.2v) and it will boost it to 6v, so your laser can operate. It is only for 405nm because a red or IR will operate at lower voltages (3v~2v) so, the driver isn't made for "buck mode", it can only "boost".
Oh. If you don't understand, I can explain again.

edit:
no, this driver would not work with a blu-ray.

 

[Sultanen]

Lemme know, your laser will reflect @ 2 galvo mirrors, and focus after that? I don't really get it yet...

If its doable i think that the focus lens shuld be before the galvos, after the galvos the beam will be moving and i think that it will be hard to get the same focus everywhere. Can you see a problem with using a lens with a focal length of 300mm placed some centimeters before the galvo mirrors?

Regarding the 6x diode
The SF-AW210 should do, but all depends - output power, how you can dispense heat... you want your diode to live 5000 hours?

Lets start with the duty and what i need to cool it properly. It will be turned on and off fast so i dont know how long the duty cycles will be, a print can go on for many hours but its turned off some times in the printing, when printing a layer its on for most of the time, about 2-3 minutes at max, after that it might be 5-10 seconds before the next layer is started, maby less.

For the life of the diode, i need atleast 500-1000h but ofc more woud be great.

Regarding the driver
Commonly, the 405nm laser diodes operate at a higher voltage (around 6v) so those drivers are "boost mode" drivers, so you can insert a single li-ion battery (3~4.2v) and it will boost it to 6v, so your laser can operate. It is only for 405nm because a red or IR will operate at lower voltages (3v~2v) so, the driver isn't made for "buck mode", it can only "boost".
Oh. If you don't understand, I can explain again.

edit:
no, this driver would not work with a blu-ray.

I understand, i can feed the driver with 15v and reduce it with a regulator, might be best if i build my own driver with a voltage regulator limiting the voltage to 6v or whats needed.

 

[Leodahsan]

Oh well, Focus before the galvos? I don't think that will work with a single focal lens. Do you need to focus the laser to a pinpoint? :thinking:

If you want life, you should operate it inside the safe operating area... It is a lot lower than we hobbyists operate those at.

You need to operate the diode @ CONSTANT CURRENT mode. You don't limit voltage, you limit current. The voltage will vary to supply that constant "current" you set. You can do that with a LM317 but, if you need modulation, you will need a constant current TTL driver (for turning the laser on and off using hardware). An ANALOG driver allows for power control too.

 

[Sultanen]

Oh well, Focus before the galvos? I don't think that will work with a single focal lens. Do you need to focus the laser to a pinpoint? :thinking:

How would you solve it? I dont care if its placed before or after the galvos as long as i get a small beam, the smaller the dot is, the better resolution i can get with the printer, with a resolution of 4096 dots in 15cm the optimal beam size would be 0,04mm. I dont think that i will get a beam that thin but then you know the target atleast. Im looking for a solution that gives me a resonable tiny dot to a resonable price :yh: Im not looking for the perfect result now, im looking for a way to get started, after that i will need to finetune and replace stuff as i find bottlenecks.

If you want life, you should operate it inside the safe operating area... It is a lot lower than we hobbyists operate those at.

You need to operate the diode @ CONSTANT CURRENT mode. You don't limit voltage, you limit current. The voltage will vary to supply that constant "current" you set. You can do that with a LM317 but, if you need modulation, you will need a constant current TTL driver (for turning the laser on and off using hardware). An ANALOG driver allows for power control too.

I placed an order for a PHR-805 from odicforce yesterday, a cheap thing to replace if i kill it. I dont expect it to work to long but i will limit the current below recommended and just print slowfor a start.

To drive it i orderd this:
Laser Driver Board V1 - 80-300mA+ optional TTL - Detailed item view - OdicForce Lasers Online Shop

Im happy to hear that i did the right thing then :yh:

 

[Leodahsan]

Right, your purchase should work :gj:. Anyways, I'm not an expert in optics, the only way I can imagine that working is to use a beam expander. It will not expand the beam fyi, it will condense it.

BUT divergence is related to the beam diameter. So condensing it will make it diverge more IIRC... Dunno. I'd just attach the laser to a X-Y config and make it move over the target, focused down :wave:.

 

[Bewaver]

Hi Sultanen,

I came across your posts looking for exactly the same answers to the same questions you have. Where are you at with your project?

It all started with this very inspiring Peachy Printer: The Peachy Printer - The First $100 3D Printer & Scanner! by Rinnovated Design ? Kickstarter

The guy implemented the device McGuyver style as minimalist as it comes, I love it. Plus the Z axle system is revolutionary, I was seduced by its simplicity as opposed to the extremely sophisticated machines you find out there for 10 grand.

So I set out on a journey to look for the same thing (as I missed the deadline), but there is absolutely nothing similar out there.

This laser discussion is very interesting indeed, here is some specs for the Resins they sell at Maker juice (providing resin to peachy), it gives a clear indication of how, at least, this resin reacts to wavelength in terms of absorption: http://makerjuice.com/docs/SubGPlus-TDS.pdf

Keeping track of the raising resin (floating on water (genius!!!) level could be done with a sensor coupled with the drip counter (12V Dosing Pump Peristaltic Dosing Head DIY for Aquarium Lab Analytical Water | eBay) to obtain an even more accurate Z axle.

Now the big question: What laser and how to make it move?

I also found a thread on this forum about the use of Galvos apparently it would be difficult to drive it for this very purpose, as someone mentioned it they can be fast, but curing is about being accurate rather than fast. Also level of quality should be obtained with better optics, at this point plastic extrusion reaches 0.1mm accuracy on the z axle, with a very narrow beam, and with fluid z axle movements, quality could improve beyond what we have at the moment in the mainstream.

http://laserpointerforums.com/f47/galvos-compatibility-arduino-71292.html : Galvos DO NOT like PWM. ==>

Unless there is a definite answer for Glavos. I would be tempted to go with direct movements even if with inertia (especially if the bulk of the laser is on the moving head) they would limit speed due to mechanical factors, where I suspect galvos could go way faster with the right x-y-z setup. But he galvos way seems to be uncharted territory where there are drivers and open source software for 3d printing for stepping motors already. Porting this onto Galvos would imply rewriting the code. There was a PCB (arduino shield) drawn by someone on this forum to link Aduino and Galvos together but I can't find it anymore.

But if you look at the peachy printer they are using the sound card and converting the sound into variations of angle of home made galvos, he used that shortcut, but the sound card being 2 channels (x,y), apparently, he cannot stop the laser when he wants resulting in a printing logic pretty much like extrusion, with continuous output and all it implies.

I like the idea of being able to mill/engrave your parts after printing, even better would be scanning them initially (you basically would need a camera and a line for laser: I have seen it made with glass stem ==>I am sure there is better lenses than that?) the rest would be done by software, there are plenty of options for that, but the good thing the laser is already there.

Now the big question would be what laser would work for the 3 operations, and how would we modulate it (with optics and intensity) in order to obtain Scanner+Printer+Milling results.

My concern is also security, as the laser would have to be very mobile for scanning, yet less for printing and milling.

Great forum, very exciting times!!

Happy New Year to everybody!!

Be

 

[Bewaver]

Also interesting thread on the Laser type wavelenght and builds for curing Resins: http://laserpointerforums.com/f47/laser-scanner-3d-printer-application-79373.html

Regards

Be