LED color mixing and optics
LED color mixing and optics
by Myong Krois
Wed Aug 15, 2012 3:12 am
I'm looking into color mixing techniques for my Luxeon Rebel array project.
There seem to be a number of different optics available. Some are designed for PAR lamp replacement, in which case they are circular and designed for 3, 4 or led fluorescent lamps. However it doesn't seem to me that these designs would work to well for a panel which might have to have numerous clusters of LEDs on it. Also they look pretty heavy.
The one I'm considering most is the Polymer Optics 181. But I think it's kind of ridiculous to be paying more than $8 for an optic that holds $6 worth of led lights. Also it seems to be designed to create a fairly narrow beam. I wonder what will happen if I put a diffusion right on top of it. How far in front of the optic will the beams from the individual LEDs converge?
I need this array to be able to evenly light things like white walls, without any kinds of colored shadows. Also, if the image of the lamp itself is reflected in some object, it needs to look white. It's OK if there's some color variation between clusters, but individual colored LEDs should not be visible.
Every cluster of flexible led strip lighting will have at least one white LED. So maybe that will make this a little easier.
I'm also considering trying the Light Engin 10w RGBA LED. However I'm a little wary after seeing come comments to the effect that the red output in this type of part can often fall disproportionately short as temperatures rise.
Well I'm hoping to hear what others have tried that has or has not worked.
There seem to be a number of different optics available. Some are designed for PAR lamp replacement, in which case they are circular and designed for 3, 4 or led fluorescent lamps. However it doesn't seem to me that these designs would work to well for a panel which might have to have numerous clusters of LEDs on it. Also they look pretty heavy.
The one I'm considering most is the Polymer Optics 181. But I think it's kind of ridiculous to be paying more than $8 for an optic that holds $6 worth of led lights. Also it seems to be designed to create a fairly narrow beam. I wonder what will happen if I put a diffusion right on top of it. How far in front of the optic will the beams from the individual LEDs converge?
I need this array to be able to evenly light things like white walls, without any kinds of colored shadows. Also, if the image of the lamp itself is reflected in some object, it needs to look white. It's OK if there's some color variation between clusters, but individual colored LEDs should not be visible.
Every cluster of flexible led strip lighting will have at least one white LED. So maybe that will make this a little easier.
I'm also considering trying the Light Engin 10w RGBA LED. However I'm a little wary after seeing come comments to the effect that the red output in this type of part can often fall disproportionately short as temperatures rise.
Well I'm hoping to hear what others have tried that has or has not worked.
