Hacker News Reader

Comment by rjett | Hacker News Reader

Since this _is_ hacker news, can someone in the know explain the considerations that have to be heeded when developing LED technology for lighting environments? I'm much more interested in hearing about the science behind these bulbs and how it compares to fluorescents and incandescents than hearing 50 different anecdotes about peoples' LED experiences.

View on HN

So the basic operating principle behind lighting LEDs is the correlation between light output and temperature. As the LED heats up, its light output decreases. If you want a single LED to produce more light, you have to pump more current through it - meaning more heat and a resulting higher temperature, shorter lifespan and reduced efficiency. Thus, you have a tradeoff between more LEDs and lower current (higher cost and more efficient) and less LEDs and higher current (lower cost but less efficient).

Switch tries to give you the cake and feed it to you - they give you lots of LEDs, running at high current, and they manage the heat by immersing the LEDs in a liquid [liquid water has a conductivity and capacity for heat ~5x greater than aluminum even with a lower density]. But this has its own problems that you can probably imagine - not least of which is that the liquid probably absorbs more light than it gives back by removing heat.

Based on my "in the know" status, I can tell that Switch will be losing big bucks trying to sell those lights at $20 but they are working hard to cement themselves in the market early. I'm very sceptical and look more towards smaller innovators like LEDNovation and LED Integration Technology.

I agree that this is more interesting. Some basic background is at

http://en.wikipedia.org/wiki/Light-emitting_diode#White_ligh...

Reply on news.ycombinator.com