baharini
0
- Joined
- Jun 26, 2010
- Messages
- 67
- Points
- 8
Hey guys, I just want to post about my new successful first build 
I have spent over a month in research and planning for this laser, and have put as much effort as I can into making it a brilliant laser.
I will document the parts of the build. It should give you an idea of what to expect when building a laser like this.
Here are some pictures of the finished product:
Without laser heatsink:
Now I will describe the build process.
First of all I got hold of an old broken DVD burner from a computer repair shop.
I removed the red laser diode from it and mounted it in an Aixiz laser housing. I live in South Africa and found a nice supplier of these locally (just remove the existing laser from the housing): 5mW Laser module.
I then soldered two leads onto the pins of the laser diode and applied a bit of heatshrink tubing.
As you can see it all looks pretty neat.
I then built the driver circuitry. I decided to drive the diode at 250mA (a bit lower than usual), which should prolong the life of the diode and not make it get so hot) so built a LM317 driver circuit with a 5 Ohm resistor (actually it's 2 10 Ohms in parallel, which gives 5 Ohms) to limit the LM317 to 250mA using this formula: 1.25/0.250 == 5 ohms.
I also used a voltage regulator board (another LM317, in Voltage regulation mode) to limit the voltage to 6V to the current regulator, to prevent any surges and smooth it out. I put this on afterwards, after blowing a previous laser diode due to a power spike.
I mounted it all in a transparent box so it is easy to observe the components. I extended the wires to the two LM317s and mounted them to a thin metal heatsink. They get rather warm without it, so this heatsink works OK
I am using a simple DC power jack and a toggle switch to power the first voltage regulator, which in turn powers the rest of the circuit.
A quick test run confirmed that it all worked
However, it got hot in a short time. I needed to cool it down.
I found an old heatsink lying around and bent the fins to fit the laser housing inside. I got it to be as tight as possible, and applied a little thermal paste.
The heat is dissipated and seems to give the laser a very high duty cycle. Plus running it at only 250mA makes it less hot anyway.
BEAMSHOT (enhanced with smoke):
All in all this build has been great fun, and got me even more interested in lasers.
I will post something else I've done with this (laser cutter, yellow laser) in a few days
Thanks for reading, if you have any questions feel free to ask
EDIT:
I attached a fan to the heatsink of the laser housing, it was actually getting rather warm after a few hours' use. It is attached straight to the 12V power input jack, and is always on irrelevant if the laser power switch is on or off.
The fan now keeps it very cool, so cool that the heatsink is much cooler than the ambient temperature
Here are the images:
I did not add a fan to the regulators inside the project box, as after running the project for 24 hours they were a little warm, but not nearly hot.
Their heatsink was still cold other than the areas directly next to the regulators.
This was a great little addition to the project
I have spent over a month in research and planning for this laser, and have put as much effort as I can into making it a brilliant laser.
I will document the parts of the build. It should give you an idea of what to expect when building a laser like this.
Here are some pictures of the finished product:
Without laser heatsink:
Now I will describe the build process.
First of all I got hold of an old broken DVD burner from a computer repair shop.
I removed the red laser diode from it and mounted it in an Aixiz laser housing. I live in South Africa and found a nice supplier of these locally (just remove the existing laser from the housing): 5mW Laser module.
I then soldered two leads onto the pins of the laser diode and applied a bit of heatshrink tubing.
As you can see it all looks pretty neat.
I then built the driver circuitry. I decided to drive the diode at 250mA (a bit lower than usual), which should prolong the life of the diode and not make it get so hot) so built a LM317 driver circuit with a 5 Ohm resistor (actually it's 2 10 Ohms in parallel, which gives 5 Ohms) to limit the LM317 to 250mA using this formula: 1.25/0.250 == 5 ohms.
I also used a voltage regulator board (another LM317, in Voltage regulation mode) to limit the voltage to 6V to the current regulator, to prevent any surges and smooth it out. I put this on afterwards, after blowing a previous laser diode due to a power spike.
I mounted it all in a transparent box so it is easy to observe the components. I extended the wires to the two LM317s and mounted them to a thin metal heatsink. They get rather warm without it, so this heatsink works OK
I am using a simple DC power jack and a toggle switch to power the first voltage regulator, which in turn powers the rest of the circuit.
A quick test run confirmed that it all worked
However, it got hot in a short time. I needed to cool it down.
I found an old heatsink lying around and bent the fins to fit the laser housing inside. I got it to be as tight as possible, and applied a little thermal paste.
The heat is dissipated and seems to give the laser a very high duty cycle. Plus running it at only 250mA makes it less hot anyway.
BEAMSHOT (enhanced with smoke):
All in all this build has been great fun, and got me even more interested in lasers.
I will post something else I've done with this (laser cutter, yellow laser) in a few days
Thanks for reading, if you have any questions feel free to ask
EDIT:
I attached a fan to the heatsink of the laser housing, it was actually getting rather warm after a few hours' use. It is attached straight to the 12V power input jack, and is always on irrelevant if the laser power switch is on or off.
The fan now keeps it very cool, so cool that the heatsink is much cooler than the ambient temperature
Here are the images:
I did not add a fan to the regulators inside the project box, as after running the project for 24 hours they were a little warm, but not nearly hot.
Their heatsink was still cold other than the areas directly next to the regulators.
This was a great little addition to the project
Last edited:
