New to this and building own RGB laser projector

[laserlloyd]

I decided that I wanted to build one of these a few months ago before I found this forum. So far I have the following:

130mW 532nm analog laser module
500mW 637nm analog laser module
600mW 445nm analog laser module
20Kpps laser scanning galvo set which came with a showcard and power supply

Basically I want to know if I am on the right track with these or if I may have purchased the wrong items. The red and blue laser require 12VDC. I was thinking of powering my lasers with the power supply, but it has an output of 15VDC. Would a 12V regulator solve this or are there better ways to bring down the voltage.

Thanks!

[Bradfo69]

You're on the right track in general but, being on the right track also depends upon your aspirations with your projector. Usually people get into this hobby trying to re-create something they saw as a young person and that's stuck with them. Some times it's a beam show, sometimes it's a graphics show. Is this for your basement or living room or, do you have illusions of going commercial?

How did you obtain the parts that you did? I have a vision based on your description that perhaps these were purchased from someone who took apart a cheap Chinese laser and sold the parts. I could be completely wrong on that but, when you said 20kpps galvos with show card and power supply, plus with the lower powers of those lasers, that's what I envisioned. Nothing wrong with that necessarily and it's an ok start but, advising you will be easier if we know what you're working with. You'll want a separate power supply for the lasers. The scanners probably need the 15 volt and every amp they can squeeze out.

What about controlling this once it's built? What are your thoughts on software/hardware to make your lasers do something?

Welcome to PL.... kiss any hope of financial solvency good bye.

[laserlloyd]

For this build I would like to be able to do beam shows to music for personal use. Potentially in the future possibly big stuff but for now just personal.

All the parts are from Chinese sellers through ebay, and i bought each separately. Thanks for the tip on the separate power supply.

As far as controlling, I have not though that far yet. I have been looking through some posts and learning whats out there. What hardware will I need exactly, and how will it connect to and control my scanners? And for software, what do you recommend for aerial shows? Anything that is robust, good for beginners, and as inexpensive as possible is ideal.

Thanks!

[Bradfo69]

You're going to get a lot of answers on here as different people have different software packages they prefer. I own (and use) a variety of software packages. Some will say I'm a "fan boy" but, as far as a new person is concerned and really being able to do the most, in a short period of learning time, that's robust as you put it, and good for beginners, Quickshow from Pangolin is your best bet. It's not the cheapest out there but, it's sort of the heart and soul of what you're going to be doing. Unless you're really a software geek and into figuring out unfamiliar terminology and symbols and what they do, some of the less expensive software and DAC controllers I feel can be awfully confusing to even a seasoned laser person, let alone someone brand new. Some of the cheapest programs out there such as iShow are garbage. Some programs can do extraordinary things in the hands of the right people such as LSX but, I think LSX is much better for creating abstract and graphic shows, than it is beams. Spaghetti. developed by a member on here is also a good starter program and is compatible with a large variety of DAC's. I can't honestly say how good it is for live beam work though.

Quickshow retails for around $595 and is one thing in this game that keeps it's value so, even if you decide that the laser thing isn't for you, it would most likely sell here in minutes for the bulk of what you paid for it. The other advantage is there is a ton of available content out there that you can play that has been created by other users so, you can see how to put together a show and have things to play for your own enjoyment.

Essentially it goes like this. Software on a computer is sent through a USB port to a DAC which converts the signal into something a laser projector can understand. You then use a DB25 cable (also called an ILDA cable) which is really just a computer cable sometimes used for printers, to carry the signals from the DAC to your projector. Your projector is going to have an ILDA port (you might see this on your show card), that it plugs into. Usually, your scanners, lasers, interlock, power switch and other things will probably get connected to that (the show card) as well. It really depends on the card. If you can, post some pictures of what you've got so far. You'll need a baseplate to mount everything on, some dichros and mounts to be able to mix your red, geen and blue, the additional power supply and you should be on your way.

[planters]

To begin, welcome.
Over the years, I have visited other technical forums such as AVS and various high voltage sites and have been comparatively disappointed in the support available when compared with PL.

I agree with Brad that unless you are quite sophisticated with computer programing and pretty adept with electronics you will be better off buying a copy of Quickshow (it comes with the compatible DAC) all you need is the cables. The time you save is worth a lot. If you'll take some advise from someone that started at the beginning a few years ago and has built all of his own systems, start out with just one color on an oversize base plate (allows for future upgrades to multicolor as well as to larger, more powerful modules when you're ready).
You will need a driver assuming the modules you bought do not incorporate one. Look for a modulation control line along with (+) and (-) power lines. If there is no modulation line then you will need a separate driver. You do not want a voltage regulator, you want a diode driver. These will automatically provide the right voltage for the diode from a fairly wide range of voltage supplies and the driver has a modulation input line (typically 0-5V) that directly attaches to the DAC and controls the laser output power (up to 250 kHz). Do not attempt to power the diodes directly from a power supply. Frequently these produce a small voltage spike on powering up that can damage a diode and the resistance of a diode can be so steep (even negative) that when they begin to conduct they can easily over-conduct to damaging current levels long before your hand can intervene.

Quickshow, a power supply, a laser module, a galvo scanner and obviously some cables and a computer is all you need and you can produce your first shows.

[mixedgas]

Lets make sure your galvos need +/- 15V first.

Take a look at the board and see if there is a 3 pin TO220 package LM7815 Voltage Regulator and a 3 Pin TO220 Package LM7915 Voltage Regulator on the scanner amps.

I am asking because most amps need +/-24 V. They step the 24V supplies down to 15V for the op-amps.

You may have the odd pair that needs +/-15V, so I'm asking.

[tribble]

You may have the odd pair that needs +/-15V, so I'm asking.

FWIW, the cheap chinese 15K amp in the Spencer laser is also a +- 15V unit.

[laserlloyd]

I looked into the QuickShow and it does seem like a really good program. How much is the Spaghetti program you mentioned?

Here are pictures of what I have so far:

Showcard



Scanners and drivers


Power supplies. One on the right is 15VDC output, it came with the scanner set. The one on the right is 12VDC output, I pulled it from a wall charger.


Green laser. It takes 120VAC input


Blue laser


Red laser


I have tested all the lasers and they work. A couple of other questions. Where is a good place to buy the dichros? And what is a good sized base plate?
And if you have any comments or suggestions on what I currently have please let me know!

[White-Light]

One thing not mentioned yet is with QS you can upgrade to Beyond (their professional level software), by paying only the difference in price between what you originally paid and the cost of the Beyond package), so you don't have to sell your controller, make losses and then start again. Also, there are regular holiday sales, where packages including upgrades are sold more cheaply than usual. These usually correspond to Christmas and Easter from memory.

The offers usually cover purchases from Pangolin direct or authorised dealers.

[Fearless]

I just upgraded to Beyond, and oh boy, what a difference. Just the ability to take in 3D objects from programs like Sketchup and laser animate them is worth the price of the upgrade.