I am building a laser maze and have ordered a variety of lasers from 5mW to 20mW on ebay. I want to standardize them but am trying to find the most economical one that keeps a good quality beam after a few mirror bounces.
I have ordered a few where the driver is a circuit that hangs out the back quite a bit, like this one:
INDUSTRIAL/LAB 532nm 10mW 5VDC Green Laser DOT Diode Module | eBay
That one worked great till it got hot while I was setting it up ~10 minutes continuous use. Now it is pretty dim, and gets dimmer over time. I am not sure if I damaged the diode, or the driver.
I have a metal lathe and can make some heat sink housings for the laser, but it seemed like most of the heat was from the driver, so maybe I should focus on that instead, but I am not sure why they would have put heat shrink tubing over the driver if it needed so much heat dissipation.
I am using a raspberry pi with a 16 relay setup to turn the lasers on and off and considered using a single driver before the relay and just getting a bunch of bare diodes without drivers and building my own housings with heat sinks, but if the major heat is generated by the driver, then I wouldn't have to worry about cooling the diode as much as cooling the one driver back at the control center.
I do realize that if I setup 8 lasers in parallel and start turning them off one by one it would raise the power sent to the rest, so maybe I could adjust the driver output using the raspberry pi using something like this: 0- 2100mA Adjustable Constant Current Laser Diode Driver 12V input | eBay and control it with the raspberry pi.
So I guess the big questions I have are:
I also picked up this 50 pack: 50PCS 650nm 5mW Laser Red Dot Module red laser sight laser diode laser pointer | eBay
I found the failure rate to be acceptable where about 20% of them have horrible focus, and they seem to be able to be left on for hours without any problems, but they aren't as bright as I would like, and I would love to switch to green from a visibility standpoint, but from a cost perspective, until I get all this worked out and find how to reduce my failures I will stick to the reds :)
I have ordered a few where the driver is a circuit that hangs out the back quite a bit, like this one:
INDUSTRIAL/LAB 532nm 10mW 5VDC Green Laser DOT Diode Module | eBay
That one worked great till it got hot while I was setting it up ~10 minutes continuous use. Now it is pretty dim, and gets dimmer over time. I am not sure if I damaged the diode, or the driver.
I have a metal lathe and can make some heat sink housings for the laser, but it seemed like most of the heat was from the driver, so maybe I should focus on that instead, but I am not sure why they would have put heat shrink tubing over the driver if it needed so much heat dissipation.
I am using a raspberry pi with a 16 relay setup to turn the lasers on and off and considered using a single driver before the relay and just getting a bunch of bare diodes without drivers and building my own housings with heat sinks, but if the major heat is generated by the driver, then I wouldn't have to worry about cooling the diode as much as cooling the one driver back at the control center.
I do realize that if I setup 8 lasers in parallel and start turning them off one by one it would raise the power sent to the rest, so maybe I could adjust the driver output using the raspberry pi using something like this: 0- 2100mA Adjustable Constant Current Laser Diode Driver 12V input | eBay and control it with the raspberry pi.
So I guess the big questions I have are:
- in the 5-20mW range, which needs cooling most, diode or driver?
- Which is most likely to fail first?
- Ok to group the lasers on one driver?
- Which is most likely to fail first?
I also picked up this 50 pack: 50PCS 650nm 5mW Laser Red Dot Module red laser sight laser diode laser pointer | eBay
I found the failure rate to be acceptable where about 20% of them have horrible focus, and they seem to be able to be left on for hours without any problems, but they aren't as bright as I would like, and I would love to switch to green from a visibility standpoint, but from a cost perspective, until I get all this worked out and find how to reduce my failures I will stick to the reds :)