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A "Bill of Lights" to Restrict LEDs on Gadgets?

Posted by ScuttleMonkey on from the palm-flower dept.

PetManimal writes "Mike Elgan has had it with useless lights on gadgets and computers. He singles out the Palm Treo and the Dell XPS gaming laptops as being particularly bad with the use of unnecessary lights, and also cites the plethora of LEDs on desktop PCs and peripherals. 'My PC and other computing equipment make my office look like a jet cockpit. I have two LCD monitors, each of which has two indicator lights that flash even when the PC is turned off. The attached sound control has a light on it. My keyboard has multiple lights. The power cord has lights, the printer has lights, and the power button is illuminated. My cable modem and Linksys router flash like crazy all the time. Together, these useless lights create a visual cacophony of blinking, multicolored lights that make me feel like I'm taking part in a NASA stress test for astronaut candidates.' Elgan calls on manufacturers to respect his 'Gadget Bill of Lights' to restrict the use of nag lights and allow users to turn them off. He also says the industry should pay more attention to industrial design when creating new products."

4 of 729 comments (clear)

  1. Re:Wow... by OrangeTide · · Score: 5, Informative

    You wasted more electricity for that remark (the routers and servers along the way had to use electricity for that message) than all the LEDs in your home. a bright LED is like 50mW. You'd need 20 bright ones, or 50 normal ones on all at the same time to make a Watt.

    --
    “Common sense is not so common.” — Voltaire
  2. Treo Solution by blackmonday · · Score: 4, Informative

    If you have a treo, download LedOff. It's donationware, and solves the LED annoyance.

  3. Except on the really bright ones. by Kadin2048 · · Score: 5, Informative

    I've found out by experience though, that electrical tape isn't 100% opaque; put a bright enough LED under it, and stretch the tape a bit (as you might if you're putting it tightly over an protruding LED), and it'll shine through.

    For really bright lights, a small square of aluminum foil works well, and is absolutely opaque.

    --
    "Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
    1. Re:Except on the really bright ones. by Falladir · · Score: 5, Informative

      I know you didn't mean that seriously, but I think you might be surprised how thin the foil has to be for light to pass through it. The quantity of interest is "skin depth". You can calculate it with the formula here, which uses several constants that are pretty easy to find:

      frequency of visible light: 600 THz (source)
      conductivity of aluminum: 3.8 x 10^7 siemens per meter (source)
      permeability of free space: 1.3 x 10^(-7) weber per ampere meter (source)

      I calculated that the skin depth of aluminum is 8 nanometers. This means that the thickness of aluminum needed to stop 99.9% of the light is one 400,000th of an inch. For comparison, this is 10,000 times thinner than the thinnest aluminum foil available from McMaster-Carr (it's a company that sells materials for scientific research, among other things). Since the atomic radius of aluminum is 125 pm, this foil would be only 250 atoms thick, and would still block 99.9% of the light.

      By the way, if you've never used it, you should check out Google's calculator. It handles units for you, so it makes calculations like this really fast.