Hello. I am hoping to explore the light therapy that NASA developed.
This video features a homemade one.
He uses 80 LEDs in what looks to be a half breadboard. I'd like to build something similar using infrared LEDs of a wavelength from 780 to 950nm.
I've heard from a researcher in this field that the upper limit of power density is 100mW/sq cm for these devices. So I'm wondering, were I using a half breadboard (300 holes), what infared LEDs and resistors would I need to fit as many as possible without exceeding the power density limit?
Please explain how to calculate the power density and what specification of the LED would make sense to look at. Also, when looking into LEDs, I saw a variety of viewing angles. When comparing two LEDs of the same light output in terms of wavelength and lumens, would it be reasonable to say that the concentration of light pointed in one direction would be higher for the LED with the smaller viewing angle? I'm equating this to the breadth of a flashlight beam - the tighter the breadth, the further you can see in one direction - but I'm not sure if this is the right way to think about it. The hope is to get as much light into the skin per LED as possible.
Thanks
This video features a homemade one.
He uses 80 LEDs in what looks to be a half breadboard. I'd like to build something similar using infrared LEDs of a wavelength from 780 to 950nm.
I've heard from a researcher in this field that the upper limit of power density is 100mW/sq cm for these devices. So I'm wondering, were I using a half breadboard (300 holes), what infared LEDs and resistors would I need to fit as many as possible without exceeding the power density limit?
Please explain how to calculate the power density and what specification of the LED would make sense to look at. Also, when looking into LEDs, I saw a variety of viewing angles. When comparing two LEDs of the same light output in terms of wavelength and lumens, would it be reasonable to say that the concentration of light pointed in one direction would be higher for the LED with the smaller viewing angle? I'm equating this to the breadth of a flashlight beam - the tighter the breadth, the further you can see in one direction - but I'm not sure if this is the right way to think about it. The hope is to get as much light into the skin per LED as possible.
Thanks