Recommend an RGB Analog module for DIY system

[nulltrope]

Hey there!

I started this hobby a few months ago by building a DIY kit mostly with cheap parts from Aliexpress. A no-name 30k galvo scanner kit (with controller/driver, SD, DMX, ILDA input) and one of those all-in-one 500mw TTL RGB modules.

While things are working decently well, i'm looking to upgrade the TTL laser to a proper analog for better color blending, and probably step up the power too (nothing too crazy though, as this would mostly be used indoors).

I'm looking for something ideally in the 5-10W range that is relatively affordable, and small in size. Size is important because the whole assembly is currently mounted in a modified pelican case for easy transport.

I know of Golden Star Laser but most stuff seems out of stock on their site, and also they seem to mostly be higher wattage RGB modules than what I need.

Does anyone have experience with any of the other more budget modules, that would be within my wattage spec and also smaller in size? Thanks!

[buffo]

There are several suppliers in China that can sell you the diode modules you'll need to build another projector, including Goldenstar, Able, and OptLaser, but if you only want something in the 500 mw - 1 watt range, you might be better off building your own modules. This is a *great* way to learn more about lasers, and it's also supremely satisfying to see first light from a projector that you built yourself.

Back in the early days of the forum, nearly all of our members (including me!) got started in this hobby by building their own projectors from scratch. If you look back at some of the discussion threads from, say 2006 through 2012, you find lots and lots of information about how different people attacked the problem.

Also of note: assuming you are in the USA, purchasing bare components like diodes, drivers, mounts, optics, etc and assembling them yourself means you will not run afoul of any CDRH regulations that pertain to purchasing or importing laser products. (At least, so long as you don't sell the projector afterward or try to use for a public show.)

Believe it or not, unless you already have your laser product manufacturer's variance *AND* you file FDA form 2877, buying a non-certified projector from China, or even just a functional laser module with a power supply, and having it sent to your house is illegal under federal law, even if you only ever intend to use the projector for your own amusement in your basement. Yes, people do it all the time, and lots of people get away with it, but there's always a chance your shipment will be the one that gets flagged by customs. Fair warning.

Building your own laser modules isn't nearly as difficult as you might imagine. Provided you can operate a soldering iron, you should be fine. You can purchase bare laser diodes from DTR's laser shop, and you can also buy the mounts and lenses you will need from the same shop.

Sourcing an affordable laser diode driver that supports analog modulation might be a little more difficult, but perhaps someone else can offer suggestions on where to purchase one today. Worst case you could build your own driver from one of the many designs available on Sam's Laser FAQ. (This LM317 based design is quite affordable to build and it worked well when I tested it a long time ago.)

You can buy the scanners, dichros, and kinematic mounts from any of the Chinese suppliers mentioned above. (These are perfectly legal to import.) On the domestic side, Edmund Optics is a good source for high quality dichros, and Thor Labs makes very nice kinematic mounts, but the prices at these domestic suppliers are going to be a bit higher.

Finally, where are you located? (You didn't include your location when you set up your user profile.) If you are close to some of our members, you might be able to meet up with them in person to compare notes. Also, just a shameless plug for SELEM (the South Eastern Laser Enthusiast's Meeting) which is coming up next month; attending SELEM is a great way to jump-start your journey into lasers. You'll meet a diverse group of people, see all sorts of cool equipment, get a chance to test-drive other people's stuff, and get lots of advice and guidance on how to proceed. (Plus it's a lot of fun!)

Adam

[nulltrope]

Adam, thank you for the reply! I definitely have interest in building my own module "from scratch" that is, sourcing the diodes and assembling the mirrors, mounts, etc. Will definitely check out the resources you linked. Also, I am based in New York so a bit far from the South East but sounds like a great time. Cheers.

[mixedgas]

John at Technological Artisans in Brooklyn NY, legally sells Analog and Analog to DC/ PWM modules at levels from 2 watts to burns holes through darkly painted car doors.

The combo Analog /DC biased /PWM module has incredible linearity and is programmable.

347-606-1076
info@technologicalartisans.com

He's on the road a bit and does gigs, but he will get back to you.

Steve

I

[buffo]

I am based in New York so a bit far from the South East.

So, fun fact: The South Eastern Laser Enthusiast's Meeting is no longer being held in the southeast.

Initially, SELEM was held in Newton, North Carolina, which is about an hour outside of Charlotte, NC. So back then, the name accurately described the location of the event.

However, in 2021, after years of struggles with the venue in Newton, we moved the event to the Executive Banquet and Conference Center in Newark, Delaware. This new venue is about 45 minutes south of Philadelphia, PA. If you're coming from the north, it's right off I-95 South just before you cross over from Delaware into Maryland.

This new venue is a *lot* nicer than the one in Newton. Also, it's managed by Brad Billet (Bradfo69 here on the forum), so thanks to him, we have full access to everything in the building, including the full commercial kitchen and the 3 phase power out near the loading dock. No other venue would likely allow us to do the sorts of things we do at SELEM. (Can you imagine trying to get permission to make liquid nitrogen ice cream in a ballroom?)

So yeah, we still call it SELEM, but the name no longer reflects the physical location of the event. But since this will be our 18th year, it's pretty clear that we're not changing the name just because we're no longer in the southeast.

Here's a link to the sign-up thread that has more information about SELEM.

Adam

[TheHermit]

Hey there!

I started this hobby a few months ago by building a DIY kit mostly with cheap parts from Aliexpress. A no-name 30k galvo scanner kit (with controller/driver, SD, DMX, ILDA input) and one of those all-in-one 500mw TTL RGB modules.

While things are working decently well, i'm looking to upgrade the TTL laser to a proper analog for better color blending, and probably step up the power too (nothing too crazy though, as this would mostly be used indoors).

Upon returning to this scene from the 80's era of ion systems, I became acquainted with modern diode lasers & galvos, just as you have, by ordering cheap RGB modules online, knowing I would modify them, without much lost from potential screwups.
Following Christopher Short's lead, I initially used LSX w/Etherdream 3 for software & ILDA compatibility, prior to developing my own laser synth.
Unimpressed with el cheapo projectors, I soon upgraded to OPTlaser's PD3000 RGB projector w/DT-40 galvos and a much improved 3W RGB module. (No longer available)
Duplicated that RGB module for a matching DIY build, but using C506 galvos.
Now, I'm doing a custom build from scratch, using Live LaserSystem, Austria's EMS8000 galvos, w/drivers & Sparrow diode modules w/ColorDrive One + TEC drivers. These are the best I've found for in home DIY projectors, which don't require all of Kvant's expensive public safety features, such as zone mapping, scanfail, etc.
BUT YOU STILL NEED A KILL BUTTON!!
Less expensive than Kvant, but w/o sacrificing excellent quality.
TBH, I've found 3W RGB to be more than sufficient for beamers, even with projecting onto black flame retardant screen material, and have experienced sore eyes after long sessions. Plus, my video camera requires a ND filter to avoid over saturation.
Play safely, especially around children and flammable objects. 5W must be handled with respect.
The aforementioned new abstract imaging projector build will only be ~1.5W (after RGB balancing).
As you've noticed, very few major projector mfrs still cater to low power, small quantity needs of amateur hobbyists.

EDIT: Just checked out Steve's referral to Technological Artisan. Coincidentally, the Clubcat HP RGB 3W projector (w/o software nor ILDA DAC), offers the same EMS8000 galvo and ColorDrive upgrades, as I've mentioned @ $4,320. (presumably, the laser diodes are from the same source)

The following similar parts, but 1/2 the Wattage, for my next DIY build were ~$2800, w/o case, dichroics, nor PSU. So, the fully compliant 3W Clubcat appears to be a pretty reasonable deal, IMHO. But, of course you'll still need an ILDA DAC, controller, & software.
Ya only gets whatcha ya pays fer.
Parts Layout.jpg
As Adam rightly forewarned, despite having had 0 previous problems with importing from OPTlaser and other Chinese sources, these OEM parts were impounded by a Fedex Customs agent for a month, until both the mfr and myself filled out forms, pledging that they would never be resold, nor used in public, and properly disposed of upon completion of 'scientific development'.
IMHO, DT-40 or the newer DT-50 galvos (which I haven't tried) are a good enough compromise between performance and price for most hobbyists. That brings the 3W Clubcat pricetag down to $2500. But to compete for ILDA awards, you'll need the similar tools as the pros.
Choose the proper tools for your objective:
Your el cheapo projector components are perfect for upcycling into lumia projectors, which don't require accurate high speed scanning nor analogue color modulation. TTL PWM can be used for apparent color mixing. Mike Gould, aka Clickamouse is the lumia expert, with lots of video tutorials on his YT channel.
YT videos of abstracts (the real essence of the artform) don't need > 2W RGB and Dragon Tiger galvos are quite adequate. But, color balance and small circular beams are preferable over rectangular el cheapo optics.
Public stage shows require lots of truss mounted beamers, scan fail protections, variances, LSO license, ... IOW, major investments into either X-Lasers, Unity, or Kvant, Pangolin Beyond, & FB4 in order to become trained and LSO certified to compete with the 'big boys'.
They're trending towards preprogrammed laser effects being controlled via DMX queues from the lighting director's desk, under the supervision of an LSO.
Those clients are usually production houses and lighting companies, who already have established relationships with preferred laser subcontractors.
Same with animated graphics for commercial A/V production clientele, who demand the best possible galvos, like Saturn 5, also available inside top shelf Kvant projectors.
There's virtually no middle ground between home hobbyists and professional show markets.
Choose your own path and gear accordingly.
Everybody's somewhere.
Hope this info helps.
Welcome to the laser world.
Roj
😎