High Power Laser Build With Thermoelectric Cooling

Here’s a fantastic tutorial from Jay, a DIY lasers expert. This tutorial will walk you through building your own incredibly high power laser and cooling it using Peltier plates. The peltiers are cheap and so is the box, fan, and heatsink. The big expense is a Meredith glass lens, the FlexDrives, and the twin LiPo’s with alarm.

Don’t miss our other DIY laser builds:

• Desk Top Helium Neon Laser Lamp
• Make a Laser Matrix Projector for the iPhone
• How to: Pocket sized 7 Color Laser with Spiro Projector

Materials you’ll need:

• Peltier
• Blower Fan This fan fits inside the Peltier heatsink with very little modification!
• Heatsink for the Peltier
• Meredith Site (for the module, lens, and module Heatsink)
• Box (Enclosure)
• Batteries
• 405-G-1 glass lens (can be fit for AixiZ module) 26% increase in power vs AixiZ acrylic for blu-ray!
• LiPo Alarm
• FlexDrives

The Build:

Starting the Blu-ray ‘Ice Box’ now… and I will show some pictures if anybody ever wants to follow this project… The heatsinks that came with the peltiers, will be used as a ‘base’ for the Ice Box build.

Overview of box and base parts with fan and heatsink.

You can see the heatsink fins through the bottom. I put some holes in the box, as well as the lid. I figure that some ventilation couldn’t hurt right? The fan fits nicely inside the peltier heatsink/base piece with very little modification! Just use some double sided tape. The other base piece will house the switch and main wiring harness. As well as the LiPo alarm.

It’s great how the base pieces are such a nice fit for the box! Next steps! – Here’s some more pictures as this new build progresses. Dual FlexDrives mounted with easy access to the pots!

Here you see the 7805 regulators. There are a couple of things I would like to mention here. I figure that probably just one regulator could have been used to power the two drivers as well as the fan, but I found them to be a nice way to mount the Flexdrives! They are cheap enough anyway…

• Notice the thin Mica sheet in between the peltier and the 7805 regulators. (to give a little insulation there)
• Notice also the little heatsink on top of the metal (heatsink) parts of the 7805 regulators. I put this there for two reasons, to give some more heatsinking for the regulators, and also to further ‘stabilize’ the build, linking the two drivers together and making the mount strong. (The metal back/heatsinks on the 7805 voltage regulators, are ‘ground’, so they can be connected together. Since the drivers are running in parallel from the same battery supply, they are already electrically connected)

The 5 volt fan will be given it’s own regulator too! Might as well, they are not expensive.

Note: At the finish of this project, I found that using 3 separate 7805 voltage regulators robbed too much of my supply voltage. So, the fix was to run only two separate voltage regulators. One for the Peltier driver, and the other one runs both the fan, as well as the driver for the LD. Works perfectly! I just finished up the wiring. Seems to be the most tedious part.

Build tip: Beam alignment…

Before you adhere the peltier and assembled parts onto the peltier heatsink, I recommend:

• Setting the diode driver to a low current, like 80mA’s or so.
• Having the supply leads to the LD driver available to test. (ends striped)
• Adjust focus, and position module with set screw.

Now… Once everything is ready, mix the Arctic Silver adhesive and spread a thin layer on the heatsink. Hold the Ice Box against a wall, and pointing toward a corner, use a single 3.0 volt lithium battery (or 3.6 ), to light up the LD so you can make sure your assembly is glued on straight by checking to see if the beam is ‘straight’, and the dot hits the corner at where it should. You will have maybe 5 minutes to make this adjustment before the Arctic silver adhesive sets up.

You not only want the beam to be straight, but you want to make sure that the module protrudes through the box, without touching the box. As the module is cooled, but the box is not. (other adjustments in beam alignment can be made by simply loosening the module set screw, and turning the module)

Final Step:

I have my peltier set at 546mA’s, the fan draws about 192mA’s, and I want to set my LD at 186mA’s. This adds up to 924mA’s. Armed with this information, I am going to go ahead and do some adjustments in my wiring to disable one of the 7805 regulators. Then I will bring leads from the 7805 voltage regulator at the fan, to the FlexDrive for the LD.

Success! The peltier driver has it’s own 7805 voltage regulator, and the LD driver and the fan share another now. I did a 5 minute run at 186mA’s. It was rock steady at 166mW’s. (AixiZ acrylic – back opened) The temperature of the block DROPPED 2.5 degrees during the 5 minute test run! It was noticeably cooler to the touch.

Awesome! I’m now the proud father of healthy twins! I’m going to leave the settings as they are for a while and see how it goes. I am amazed at the result of the 5 minute test run of the blu-ray Ice Box @ 186mA’s! To go for 5 minutes at this current, and the temperature of the Meredtih mounting block actually got LOWER!

This will be the future home of a 6X diode! I know…all the labels and stuff look kind of ‘cheesy’. But it’s important information to keep track of. This way, I don’t have to go looking for it.

For now, the PHR is giving a steady 209mW’s through my 405-G-1 glass lens modification! (26% increase in power vs AixiZ acrylic for blu-ray)

The Long open can red is giving 316mW’s through the Meredith glass lens! (20% increase in power vs AixiZ acrylic for red) Both of these lenses can be fit for AixiZ modules – the Meredith, as well as my 405-G-1 glass lens mod…

Final results:

(Beam shots – with smoke)

You can also check out a video of my ‘Ice Box’ red TEC laser lighting a match from 20 feet away…

Hope you’ve enjoyed my project! – Jay

This post was submitted by a Hack N Mod fan, just like yourself. If you’d like to earn money from your projects, feel free to contact us.

HacknMod.com © 2013