Hereâ€™s another fantastic tutorial from Jay, a DIY lasers expert. See all of our DIY laser projects. I picked up this little key chain light at Lowe’s. It is made from a solid piece of brass. It is very heavy duty, but very small.
Beam shot – with smoke. This is a 405nm ‘blu-ray’ laser diode. My camera happens to capture the true ‘violet’ color of the blu-ray using smoke.
Important: This is a class 3B laser and should be used with care. Proper eye protection for 405nm wavelength recommended. It can instantly damage the eye if it is pointed directly into the eye. Even reflections can cause eye damage.
I managed to get a FlexDrive inside there for an 803T blu-ray build! (then I made a red build, and then I made a 6X build – 268mW’s!). Here are the build pics:
I found that the stock, ‘stacked’ button cell batteries were not enough to run a FlexDrive. The answer was to use a 3.6 volt Lithium 10180 battery. Or better yet… the tail cap can be drilled out to fit a 10280! The 10180 batteries are 90mAh… But the 10280′s, are 180 – 200mAh’s!
With this in mind, I chose the highest efficiency PHR diode that I could find to keep the current as low as I could and still have good power! 117mW’s @ 117mA’s! With a 10280, that should give around a 1 hour run time per charge.
For the 10180 fit: I shortened the spring on the tail cap just a little, because the 10180 is just a little longer than the 3 stacked button cells that came with the host. The only other thing that I did, was to bypass the little button circuit on the stock board to make it a momentary button switch.It had some kind of little circuit that allowed it to be a constant on / off switch, but this did not work with the FlexDrive, so I just bypassed the circuit…
Notes: Figure a setting of about 130mA’s to give (normally) 115mW’s of blu-ray with the 803T diode for around a 1 hour run time between charges with the 10280 battery. For a red, 275mA’s still gives me 200mW’s using the Sony/Senkat SLD1239JL-54 diode, along with the AR coated acrylic lens that I have linked below. I bought these from e-bay.
Considering run time (boost vs buck vs diode used), IgorT did some calculations that theoretically should allow using a higher current with a red diode build! Because the red diode takes less voltage, and the driver doesn’t have to boost. A 200mW red, should be about the same battery life as a 200mW blu-ray. (I’m guessing about 1/2 hour at this higher current with a 10280)
Here are the AR coated acrylic lenses for red diodes. You’ll get about 10% more power with these (vs AixiZ acrylic), and they fit right into the AixiZ module! Additional mods:
- Meredith glass lens modification fit for AixiZ – 20% increase in power for red vs AixiZ acrylic! (back opened)
- 405-G-1 glass lens modification – 26% increase in power for blu-ray vs AixiZ acrylic! (back opened)
For a 6X build
A normal efficiency GGW 6X diode, set at 180mAâ€™s, will give you around 170mWâ€™s. (AixiZ acrylic lens – back opened) But with my 405-G-1 glass lens modification, you will get at least 26% more power!
Tail cap mod
I found just enough room in this host for a 10280, by drilling out the tail cap. Now there is room for a 10280 (200mAh), which is twice the capacity of a 10180!.
The AW web site where I ordered the 10280′s, says 180mAh’s, but the batteries say 200mAh’s on them. I thought I would show that it is an easy mod to expose the negative end of the battery edges. This is needed with this build using the longer batteries. Because of the tail cap mod, there is no longer a center spring.
Battery Current Draw – for 3 different builds: Here are my three different builds and the current draw on fully charged (200mAh) 10280 batteries…
- High efficiency PHR-803T blu-ray set at 117mA’s and putting out 117mW’s. (AixiZ acrylic) – 175mA’s battery current draw.
- Sony/Senkat SLD1239JL-54 red set at 275mA’s and putting out 200mW’s. (AR coated lens) – 228mA’s battery current draw.
- High efficiency (freak) 6X blu-ray set at 183mA’s and putting out 215mW’s! (AixiZ acrylic) – 288mA’s battery current draw. (268mW’s using my 405-G-1 glass lens modification!
- I”m guessing the 6X build will be 30 minutes run time (or less), but who cares?… 268mW’s of blu-ray in a Key Chain build!
Before you complete the build, make sure you check to see if you are getting a voltage reading between the negative end of the battery, and the host! If you are getting any kind of a voltage reading here, then you have not disabled the stock switch circuit good enough.
There is a connection from one edge of the board (which is ground), that goes to the center. This has something to do with the way the little circuit would let the switch be a ‘constant on’ switch. I found that I needed to ‘scrape’ through this connection to by-pass the circuit completely.
Otherwise, I got a voltage reading from the negative end of the battery, to the host. Strange… On one of my builds, I actually got a small current draw here, and it would slowly drain the battery. After I did the above ‘fix’, the problem was solved.
Here is a video showing a much less powerful blu-ray build of mine lighting matches. You can see that just a very small amount of smoke in the air from the matches will make the blu-ray beam visible. That one is only 80mW’s. My 268mW Key Chain build is much brighter!
(Beam shot – with smoke)
Here’s a photo of the laser in action. Hope you like this project! – Jay
You may also enjoy these other laser builds:
- High Power Laser Build With Thermoelectric Cooling
- Mindblowing LED, Light and Laser Photography
- How to: Pocket sized 7 Color Laser with Spiro Projector