Saturday, January 31, 2009

LED lights

I read an article today from NewScientist about new super-efficient LED lights. The short article is HERE. I won't reiterate what you can read for your self.
I love the idea of LED lighting. Now let me tell you what is currently (pun intended) wrong with them.
I bought a string of colored and white LED Christmas lights. My idea was to use them as ambient room lighting with the goals of lighting the room and saving money on electricity costs.
In the evening we returned from the store with the lights and I set up the white string across the valance in one of our rooms and plugged them in to check out how it looked. Immediately I noticed that the light is much too 'COOL' in color. A major set back. I then ran the colored set thinking that the colors would off-set the 'cool' tone. The colored set did indeed set off the 'cool' tone but it still doesn't provide the nice soft warm light of an incandescent bulb. Even the light from the CFLs is much warmer. The colored set alone is a bit too dim.
I continued to sit in the room for a while then I noticed it. Out of the corner of my eye, the 'shimmer'. I describe it as a 'micro-strobe effect'.
Have you ever waved your hand in front of a television set and noticed that you can see your fingers in a strobe type effect? Its the same thing, except that all the light in the room causes this problem. Not only when you are looking directly at the lights but the indirect light in the room as well.
I also noticed something else. This effect seems to only occur with lights that are plugged into the wall, or for you more technical types, using AC current. LED's using batteries, DC current seem to not develop this effect. If you don't understand why this occurs, read the wikipedia links posted the reason should become clear.
Clearly my observational research needs more work but my conclusions at this point are that if LEDs are to truly succeed, and I think they should, these two issues need to be solved. If not, regardless of the benefits, of which there are many, LED usage will not expand like it should.


  1. Seeing a strobe effect, huh?

    How many beers did you have that night?

  2. Nice experiment. I wonder what makes them so cool in color? I had not noticed the strobe effect, but it's been a while since we had our Xmas lights up. I too think LED's would be a nice way to go if the problems you found could be solved.

  3. One of the components of incandescent light is infra-red; LED lights don't really have much of that. Even though some of the colors aren't really visible to humans, it can affect the perception of the visible colors, in the same way that inaudible sound can affect music, giving it depth that is missing if some of the inaudible notes are eliminated.

  4. CS: i see it even when not drinking. :p
    SF: thx. i dont know what makes them so cool
    BG: I think you hit on an important component.