Question about diy laser galvo scanner

I would like to build a laser scanner, but I have a few question before buying part,

I found a galvo kit online and after reading the sticked tutorial I found out i need : a digital to analog converter, a laser and it's driver.

for projecting indoor what laser power is enough ? what driver do i need for it ? is it possible to regulate the laser intensity or it is just on and off ?

the diy dac tutorial has a guide to correct the output of the dac but it's seems that it output +5v/-5v when the galvo kit require +15/-15 volt. Do i need to amplify again ?

thanks for your help. What driver you'll need is relative to the laser. Expect anywhere from 4V-30V at maybe a couple of amps. Probably best to just get yourself a small bench supply as you're only getting started.

I looked into the idea of building a galvanometer a number of years ago but to be honest for laser light shows there are so many options for such little money. Anything you build will be mediocre by comparison as they are finely tuned systems. I think the entry level 15/30 KPPS systems run for around $100 USD. Have a look at this.

As for DACs, have you ever messed around with microcontrollers before? You can buy ILDA driver cards but from what I recall the information on them seemed relatively obscure, the cards themselves expensive, and the inputs/outputs tended to be older RS232 protocols. Although now looking through ebay I see this which claims to be good value but seems very expensive for what it is (at least in terms of hardware). If you're looking for a project maybe playing around with an Arduino/embed microcontroller and generating your own analog drive signals might be a better project?

Oh, and a +/- 5V output will just produce a smaller image. You can set up an op-amp circuit to amplify the output of your DACs but you would need +/- 18V to get the max +/-15V out for your system. Again, where a decent 3 channel bench supply would come in handy. thanks a lot for your detailled answer,

Can you post a link to said tutorial?

this tutorial show how to correct the output of a sound card wich i plan to use to make the dac, i think i misread and the input of the said corrector should be +5/-5

laserpointerforumsXcom/threads/sound-card-dac-tutorialX/page-3#post- (replace the X with dot)

Have a look at this.

this type of kit is what i plan to buy, but it's not complete as the dac and laser is missing. I think I will follow your advice since I've already messed around with microcontroller and amp op.

but last question is for the laser, I wouldlike to know if it's possible to buy a higher powered laser and change it's intensity so i can use it both for light show and laser engraving or laser only function at a given power.

Yes, you can control the intensity but generally they don't have linear characteristics. It varies from diode to diode however, just be aware that it won't be a case of 0-5V ~ 0-100%. You can control them with PWM but you'll be momentarily be blasting 100% power which may be dangerous if it were to reflect sharply. Invest in some decent goggles.

So i guess for security reason it's better to buy 2 different laser. If I were to power one with a standard power supply, can I make the laser blink with a square wave to draw different point for example ? or do I need a special driver made for it ? This is just an opinion, but if you are having trouble with finding info, Going to a LEM would be super helpful for you. You would get to see many projectors from the home built to professional, firsthand (Once Covid-19 dies down)
At last years SELEM, Mariomaster had a homebrew laser projector he built with minimal parts and a thrown together cage, but the output was impressive for what it was.

If you want to know all about scanners:

Try Laser Scanners Book by Bill Brennan, president of Pangolin.
Pangolin currently make the best scanners in the world, Saturns
They are stupid expensive at $ a set by special order, if you can get one and that's only just for the scanners.
But they have the best specs and it gives you a high point to know what can and can't be done.

On the other end of the spectrum are the ultra cheap Chinese and home-brew. I picked up two sets of 10K Chinese scanners for $20 each at SELEM last year from D Kumpula. Complete with driver boards. He does a lot of builds and sometimes has leftover unused parts that are basically junk but fun to play with.

If you want to know about lasers:

Sams Laser BIble by Sam Goldwasser covers almost anything you want or need to know

Otherwise read these forums for the latest info on diodes and techniques.

Links below

LASER SCANNERS: Technologies and Applications: How they work, and how they can work for your product: Benner Jr., William R.: : Amazon.com: Books

Buy LASER SCANNERS: Technologies and Applications: How they work, and how they can work for your product on Amazon.com ✓ FREE SHIPPING on qualified orders

The Laser Galvanometer Thread!
May 31, 09:29AM Registered: 12 years ago
Posts: 26 Re: The Laser Galvanometer Thread!
May 31, 04:51PM Admin
Registered: 17 years ago
Posts: 14,085 Re: The Laser Galvanometer Thread!
June 01, 07:02AM Registered: 12 years ago
Posts: 26 Re: The Laser Galvanometer Thread!
June 03, 06:47AM Registered: 12 years ago
Posts: 26 Re: The Laser Galvanometer Thread!
June 03, 07:27AM Admin
Registered: 17 years ago
Posts: 14,085 Re: The Laser Galvanometer Thread!
June 29, 04:14PM Registered: 12 years ago
Posts: 26 Re: The Laser Galvanometer Thread!
June 29, 04:52PM Admin
Registered: 17 years ago
Posts: 14,085 Re: The Laser Galvanometer Thread!
June 30, 04:45AM Registered: 12 years ago
Posts: 26 Re: The Laser Galvanometer Thread!
September 05, 09:14AM Registered: 12 years ago
Posts: 26 Re: The Laser Galvanometer Thread!
December 17, 11:07PM Registered: 9 years ago
Posts: 4