Hi again... After I posted the CAT100, some asked me about my next project, and here it is. While the CAT100 already wasn't a serious flashlight, this one is even less one. I would't dare to post it if it didn't have quite an interesting property: it's long throw ability.
The setup is very simple: just a LED and a big lens, mounted on a rail for optics experiments.
Specs are in the image. LED is thermo-glued on a 4cm*8cm*2mm copper plate, driven with a buck driver at 1.25A. Input is anything within 4-16V.
I just took a small power supply, but 2*18650 should perform equally.
I measured 472 lx @ 29.6m, which gives 414kcd (or "414000 lux @ 1m calculated", as it's often noted a bit improperly).
The beam is very thin: 10cm @ 29.6m, that's 3.4 mrad.
A good laser pointer has 1 mrad, a bad one has 2 mrad, and this thrower has 3.4 mrad... That's why I called it "needle".
I posted an earlier version with 270kcd (lower LED specs) in a thread on throw and decided to pimp it a bit 🙂
Update:
After some vacation and another trip I found time to make this one 'mobile' - i.e. slightly more compact and powered by batteries. Since it's still unwieldy, I thought it's better to carry it as a construction kit and assemble it in the field. Thus I named it Field Assembled Thrower 🙂
(I hope you recognize that naming those things is not meant seriously and should be taken with several grains of salt.)
The batteries are in a rolled paper case again... The buck driver (1.25A) is in a heat shrink tube. No switch, just plug and play 🙂
If I find the time I might finally do that one right and use an EZ900 instead, probably driven at 1.4A. I hope it then will exceed the 0.5 Megacandela 🙂
Here's a beamshot at 250m:
Small beam indeed... (oops, ignore the excess "E", please)
Need to find a good, more distant target.
The setup is very simple: just a LED and a big lens, mounted on a rail for optics experiments.
Specs are in the image. LED is thermo-glued on a 4cm*8cm*2mm copper plate, driven with a buck driver at 1.25A. Input is anything within 4-16V.
I just took a small power supply, but 2*18650 should perform equally.
I measured 472 lx @ 29.6m, which gives 414kcd (or "414000 lux @ 1m calculated", as it's often noted a bit improperly).
The beam is very thin: 10cm @ 29.6m, that's 3.4 mrad.
A good laser pointer has 1 mrad, a bad one has 2 mrad, and this thrower has 3.4 mrad... That's why I called it "needle".
I posted an earlier version with 270kcd (lower LED specs) in a thread on throw and decided to pimp it a bit 🙂
Update:
After some vacation and another trip I found time to make this one 'mobile' - i.e. slightly more compact and powered by batteries. Since it's still unwieldy, I thought it's better to carry it as a construction kit and assemble it in the field. Thus I named it Field Assembled Thrower 🙂
(I hope you recognize that naming those things is not meant seriously and should be taken with several grains of salt.)
The batteries are in a rolled paper case again... The buck driver (1.25A) is in a heat shrink tube. No switch, just plug and play 🙂
If I find the time I might finally do that one right and use an EZ900 instead, probably driven at 1.4A. I hope it then will exceed the 0.5 Megacandela 🙂
Here's a beamshot at 250m:
Small beam indeed... (oops, ignore the excess "E", please)
Need to find a good, more distant target.
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