Topic: using hdd galvos for lofi laser projector - possible?

[johannesgj]

hello guys i couldnt raise fundings for my big laser project i had written a lot about before so here goes a smaller project :-)

i am thinking of using two hdd galvos for making a lofi laser projector.
the drive for this project is that the projector would be very cheap thereby hosting workshops where people could build their own could be an opportunity.

well heres the lineup:
two hdd galvos to control xy cordinates
some sort of ac to dc converter or something to make the output of the computers audio card (two channels is enough cause the projector is gonna be monochrome)
cheapass laser maybe from dvd writer (it will only point towards the roof and not human eyes :-)

well any thoughts?
this guy made the roughly same setup though using a propeller to drive it and got ILDA 4k
http://micah.navi.cx/2008/07/hard-disk-laser-scanner-at-ilda-4k/

[James]

http://akrobiz.com/laserboy/forum/index.php/topic,73.0.html

Talk to this guy!

This is beautifully done, original work.

James. 

[johannesgj]

thanks james
fast as usual!!!
hope life is good to you with lots of colored beams from the laser gods coming you way hehe

[James]

Nice to see you here again.

I hope that you can make something that makes you happy.

James.  

[johannesgj]

two things would right now make me happy
1. two reinvent/organize some way to make a cheap lofi but vecotr able laser projector
2. make workshops where i teach people to do it and spam them with laserboy forum preaches hehe
:-)

[James]

Your first request is getting cheaper every day.

There is no end of the material you might use for your second request.

James. 

[johannesgj]

i wrote alfa a pm asking him for imput on my thread. his projects are NICE 
generally i must say that all projects on this forum come in such classy professional shape that they remind me of industrial precission work!

well i still need some input on my business here.
and the project has taken another direction. now under the headline
how to make the cheapest functioning monochrome laser projector
while still being able to project actual output from vector graphics etc.

the idea is to use galvos from hdds
however there is still problems regarding the rest of the hardware.

i have an old usb 'soundcard' laying around with a mic in eadphone out. i am thinking to make the conversion to dc on this device if i got that part right :-)

the laser is for the first time gonna be on all the time (keychain laser)

and i will use an linear actuator as shutter instead of modulating the laser. the linear actuator is also based on hdd galvo. but here connected to the serial port or maybe an arduino.

so the basic idea is to have the computer output vector sound (hehe) through the headphone usb interface to control the hdd galvos. while at the same time outputting info through serial to control the shutter.

well is this journey worth the trip or should i go with saving up for equipment instead?
another way is of cause just to make a cheap hdd galvo spyrograph thingy sound reactive just to get into laser biz :-)

[James]

You should just go ahead and make a 6 or 8 channel sound card DAC. There is already software that can use it. It would be too much trouble to try to get the serial port into the action of blanking.

You can also make a nice laser show device from two little DC motors.

You mount a small round mirror just slightly off perpendicular to the shaft of each motor.

If you bound the beam off of just one motor driven mirror, you get a cone shaped beam pattern that draws a circle when it hits a wall. If you bound the beam off of one mirror and then off of the other, you get Spirograph.

You can put computer fan speed controllers on the DC motors to change their speed and the pattern they draw.

You could also probably make a little microphone amp that clips at 5V and rectify the output to make a sound activated laser.

James. 

[johannesgj]

sounds cool but i think that again i will ditch the cheapo and go for the real dish :-)

ill go with the scanpro 20 for a start some dac maybe one of those you recomennded to me in the beginner thread.
then for start only one green laser and for blanking - dunno :-)
i think that should do it.

[James]

Build your own 8 channel sound card DAC. You will never regret it. It works as well or better than anything else available at any price; provided it has high quality input data. That input data might contain both RGB signals to control individual laser's modulation AND a channel of mix RGB values for a single color laser projector. Plus you will have two tracks left for stereo audio.

James. 

[johannesgj]

what you mean by making my own. do you mean modding it to dc or?
with the 8 channel incl rgb mix thats just genious becuase then the hardware dac takes care of you starting with only one laser. in this case you can still practice making the nice vector graphics in laserboy in colors. output them in monochrome and when you get the other two lasers bang your rgb with a library of visuals :-)

[James]

Yes. That's the idea.

LaserBoy lets you make the mono channel a few different ways. You can make it look like a gray scale, where all the colors are shades of gray (weighted or simple average) and only white is full-on, or you can use the bitwise OR function so that its full-on whenever any one of the RGB lines is full-on, or you can just make it TTL.

James. 

[Milyla]

Wow build a laser projector..DIY...That would be an interesting and challenged wotk, would take this suggestions and try when available, just gert cheaper and cheaper cost or that as you guys discussed b4!!