After discussion in the multiple luxeons in one reflector thread, I came up with this idea. The basic premise is to treat each luxeon as a unique point source of light. But rather than point one forward, point them sideways into the reflector, back-to-back on a heat sinking aluminum bar.
In order to properly focus with the reflector, the reflector needs to be split in half, and the halves moved apart from each other. This allows each luxeon to act as a point source for its half of the reflector, and for the reflector to gather the maximum amount of light from each luxeon in this configuration.
Pict-chas!
For simplicity, I left the emitters (bin Q2J) on the star boards, and just bolted them to the bar stock. The reflector is a mag reflector. I had to space the reflectors out quite a bit due to the height of the emitter. The black pieces are pieces of thick foam that turned out to be the perfect spacing height (just a hair shy of 1/4"). Between the two spacers and 1/8" aluminum bar, the reflectors are now 5/8" apart. Each reflector was positioned to produce a roundish hotspot.
Now, for results!
For each beamshot, the left is the color shot (twin luxeons on bottom), the right, greyscaled and solarized to 3BPP to show the brightness gradient
First, up against a 1W Q2J at 700mA in a 3D mag, with the twin luxeons running at 620mA each:
The greyscale shows the twin has a brighter hotspot. Looks good.
Next, against a 5W V3T in a 2D mag, at 1A:
It's no contest, the twins have a might brighter hotspot than the single 5W.
These are encouraging results!
The one thing that would make a vast difference would be a different reflector. As it stands now, the mag reflector allows probably 30-40% of the light to leak through the back of the reflector where the bulb post originally would come through. A reflector with a focal point higher up would solve this. Tighter focus would also be achieved with a larger reflector.
I am envisioning that building a flashlight around this design would be relatively easy. The head would have an oblong shape, machined from aluminum. Instead of a simple circular hole for a reflector, two half-circles for the refelctors, with a thick bridge between the reflector halves, running the entire length of the head (as it would maximize thermal transfer to the head, and would not block the beam in the least bit). One could still retain a focusing mechanism if they devised a way to move the reflectors independent of the rest of the head (not hard for an ME to figure out). Other focusing/defocusing may be achieved through spacing the reflector farther or nearer to the LED. With larger reflectors and a large mounting bridge for the LEDs, you could mount two 5-watters back to back.
So instead of the recoil style configuration that Pelican is introducing, with it's thermal management problems, a "side-shot" style light can have the benefits of a recoil style configuration (maximizing the light gathered by the reflector), use multiple luxeons for additional brightness, and not worry about achieving a good thermal path to the outside world.
CPF modders - what do you think?
In order to properly focus with the reflector, the reflector needs to be split in half, and the halves moved apart from each other. This allows each luxeon to act as a point source for its half of the reflector, and for the reflector to gather the maximum amount of light from each luxeon in this configuration.
Pict-chas!
For simplicity, I left the emitters (bin Q2J) on the star boards, and just bolted them to the bar stock. The reflector is a mag reflector. I had to space the reflectors out quite a bit due to the height of the emitter. The black pieces are pieces of thick foam that turned out to be the perfect spacing height (just a hair shy of 1/4"). Between the two spacers and 1/8" aluminum bar, the reflectors are now 5/8" apart. Each reflector was positioned to produce a roundish hotspot.
Now, for results!
For each beamshot, the left is the color shot (twin luxeons on bottom), the right, greyscaled and solarized to 3BPP to show the brightness gradient
First, up against a 1W Q2J at 700mA in a 3D mag, with the twin luxeons running at 620mA each:
The greyscale shows the twin has a brighter hotspot. Looks good.
Next, against a 5W V3T in a 2D mag, at 1A:
It's no contest, the twins have a might brighter hotspot than the single 5W.
These are encouraging results!
The one thing that would make a vast difference would be a different reflector. As it stands now, the mag reflector allows probably 30-40% of the light to leak through the back of the reflector where the bulb post originally would come through. A reflector with a focal point higher up would solve this. Tighter focus would also be achieved with a larger reflector.
I am envisioning that building a flashlight around this design would be relatively easy. The head would have an oblong shape, machined from aluminum. Instead of a simple circular hole for a reflector, two half-circles for the refelctors, with a thick bridge between the reflector halves, running the entire length of the head (as it would maximize thermal transfer to the head, and would not block the beam in the least bit). One could still retain a focusing mechanism if they devised a way to move the reflectors independent of the rest of the head (not hard for an ME to figure out). Other focusing/defocusing may be achieved through spacing the reflector farther or nearer to the LED. With larger reflectors and a large mounting bridge for the LEDs, you could mount two 5-watters back to back.
So instead of the recoil style configuration that Pelican is introducing, with it's thermal management problems, a "side-shot" style light can have the benefits of a recoil style configuration (maximizing the light gathered by the reflector), use multiple luxeons for additional brightness, and not worry about achieving a good thermal path to the outside world.
CPF modders - what do you think?
