DIY Horizontal scanner project

Overview:

I started this project about two weeks ago. Got VERY interested in lasers after attending an awesome rave and so here is the first prototype of my horizontal audio controlled scanner. The case is currently very low-tech, it's made out of cardboard and cut toilet paper rolls, stitched together with electrical tape. Accordingly, the total production cost of this scanner was less than 30 dollars (including the green laser module), which is quite acceptable when compared to the endgame.

The laser module used in the video and the first picture is a 3V, 30mW 532nm green laser module from dealextreme, driven by two AA batteries. I'm in the process of buying a 100mW one and fitting it with a heatsink.

Details of the project:

What makes this sucker tick? It's basically an old subwoofer amp connected onto a voice coil of an old HDD reading head. Superglued into the reading head is a piece of mirror. The laser is shined at the mirror.

The amp:

About ~10-15W RMS, 4 ohms nominal drive, stripped from an old creative inspire set.



It has a 3,5 mm jack in and a "bass level" controller which proved to be very handy while adjusting the scanning pattern.

The HDD:



The top cover has been removed and one of the metal bars that used to be one of the HDD's legs is now being used as a mount for the laser module. The whole thing is superglued on top of a CD case for easy maintenance.

Close-up of the amp to voice coil connection:



Not very pretty, but it works. You can see the final product in action here:

--> YouTube - DIY Horizontal Laser Scanner (30mW 532nm)<---

There is still lots of stuff to do here:

- new project case: I need to relocate the whole thing into a (preferably) metal box and add an external switch and heatsink for the green laser module.
- cut the foremost part of the HDD off to conserve space

I can adjust the width of the scanning beam by adjusting the source volume. Also running a software synthesizer and playing some bass notes results in awesome effects. I'll post some more photos as soon as I get a replacement laser module (the one used in the first picture died as a result of drunken soldering).

This thing looks really awesome in a dark room with smoke!

I really appreciate any comments and suggestions :thanks:

Cool. Nice start.

it's fun isn't it!

On to your next project... You should dry mirros on PC fans, for the tunnel and liquid sky effects (search here).

Well, what a way to start.

It's also an impressive first project.

Have you considered building a spiro?

goninanbl00d said:

Well, what a way to start.

It's also an impressive first project.

Have you considered building a spiro?

Click to expand...

Thanks for the compliment. I actually have a one-mirror spirograph ready, with a mirror superglued into an angle on top of a 12V dc fan. But I can't take any pictures right now as I don't have a working laser module. Adjusting the width of the scan beam and making it hit the spinning mirror is VERY entertaining to say at least

I've also made some DIY diffraction gratings by stripping the reflective coating off a CD and cutting it with a thin-blade mattress knife. (Hooray for versatility of CD's!)

My next project will undoubtfully be a three-mirror spirograph with 30mW green module and 100mW red.

An update folks!

The 30mW laser module has found a new home. I mounted the thing inside an old cable modem and it seems the standard threaded cable connector is about the same size as the diameter of the DX laser module. Hooray!



Now the only problem is the thing overheating when it's on. It seems after 3 minutes the diode housing becomes burning hot and the output decreases significantly. With the lid on the thing looks kinda sleek but the problem is further made worse:



So I've been thinking of adding a heatsink to the module. Only problem is I don't have the necessary tools to cut an existing cpu heatsink to about 1/4 of its original size. I do have lots of thermal paste, though.

Any ideas to reduce the running temperature of this thing?

There's a simple solution to this.

Get a chunk of aluminum. Doesn't have to be big, 1 inch squared by half an inch (or 2cm x 2cm x 1cm in the metric system) should be enough.

Drill a 12mm hole through the 1 inch and 1 inch face. Insert the module into the hole, and use thermal epoxy to mount the module to the lump of aluminium. Make sure there's about 3 to 4 mm of exposed brass on the driver side of the module.

Also- you could also use a set-screw to hold the module in place, if you wanted something that was adjustable.

If this isn't clear enough, I can get you a picture.

goninanbl00d said:

There's a simple solution to this.

Get a chunk of aluminum. Doesn't have to be big, 1 inch squared by half an inch (or 2cm x 2cm x 1cm in the metric system) should be enough.

Drill a 12mm hole through the 1 inch and 1 inch face. Insert the module into the hole, and use thermal epoxy to mount the module to the lump of aluminium. Make sure there's about 3 to 4 mm of exposed brass on the driver side of the module.

Also- you could also use a set-screw to hold the module in place, if you wanted something that was adjustable.

If this isn't clear enough, I can get you a picture.

Click to expand...

I think I know what you mean. I still would prefer using standard thermal paste, though, as I might want to replace the module in near future. Is that ok?

can you make a full TUTORIAL on this thing.....i wanna make one as i have like 50 dead hardrives with me

TTerbo said:

can you make a full TUTORIAL on this thing.....i wanna make one as i have like 50 dead hardrives with me

Click to expand...

I will, it's actually very simple. The hardest part was tracking down which leads are used to move the disk heads.

Thermal paste is fine, however, use a setscrew to hold the module in place.

cool. i cant wait to have one of these

These are pretty nice green module heatsinks from Zbolt for only $15.00 USD.
Class IIIb Green Laser Modules - > 5 mW for OEM Products, Research, Hobbies

I attached a pic

BTW, this line made me laugh: "(the one used in the first picture died as a result of drunken soldering)." :crackup::crackup::crackup::crackup::beer:

Been there, done that!!!

ok i found the connections that make the little arm move...so if i want to power this thing from my comuter i just hook the speaker and amp to the computer then what do i hook the HDD connections to? the speaker?

Put HDD to amplifier and then put amplifier on, then HDD voicecoil starts to dance!

i gota find an amp.....any ideas? computer speakers?

Computer speaker amps should be fine. A little weak, but they should do.