Blue LED Backlash

I recently purchased the DGL-4300 wireless router, mainly because it includes gigabit ethernet, which is still quite rare in routers. It certainly looks cool, as routers go, with its sleek rubbery design and all-blue LEDs. But those blue LEDs-- particularly a bank of them, all blinking away-- are blindingly bright! They're actually painful to look at, which is sort of ironic considering they are status and activity LEDs.

This is a companion discussion topic for the original blog entry at:

The gigabit ethernet and 802.11g Wireless seems worth the extra muala… that or the extreme “Gaming” moniker in the product name. Actually the GamerFuel feature of being able to control uplink traffic makes it a buy for me. Did you buy that router directly from Dlink shop? Any deals?

I got mine from newegg, I think… there was a rebate deal going at the time.

The main thing I don’t like about this router is that it does not support UPnP.

Blue light has longest wavelength - that’s why the Reds and Yellows get filtered out as one gets deeper and deeper underwater (I dive) while Blues persist until all light is lost. Don’t know what that has to do with tiring the eyes, but there’s a little trivia for you.

umm, try the SHORTEST wavelength

yeah, trentblase is right. blue has the shortest wavelength, hence blueRAY DVD’s using blue light to burn smaller lines with higher accuracy making a DVD able to fit 50GB instead of 4.7…

Wow, the above comments really do illustrate the sad state of science
literacy in the US

Did anyone else have to memorize ROYGBIV? The rainbow colors in order of decreasing wavelength.

Incidentally, the peak spectral response of the eye is in the yellow-green part of the spectrum.

LOL – “technology to produce lower output blue LEDs”… all they need to do is reduce the current through the indicator LEDs using a higher-ohm resistor in series.

One option I’ve used is to paint over blue LED indicator lights on my mouse, and other devices, with a green fluorescent paint. The shorter wavelength blue causees the paint to glow, thus converting the blue LED indicator into a more diffused green indicator.

Ah-hah, good old conversion phosphors. Isn’t it funny? Scientists went to all the trouble to invent high-intensity blue LEDs, then marketing departments dictated that all new products use these LEDs because they’re way-cool (and will become symbolic of this decade in a generation or two) and they’re much more expensive than the alternatives, and then users paint over them with green fluorescent paint to turn them back into dim green LEDs.

What would be even funnier is if the router ran off a wall wart (hey! it does!), which was plugged into an 110VAC inverter, which was plugged into the 12VDC outlet in an automobile, which was powered by an (AC) alternator, powered by a gasoline engine.

I agree with your observation that blue LEDs are annoying and seem to be brighter than red or green. I had a similar experience with a Netgear wireless router installed in our bedroom and ended up putting the router in a cabinet so I could sleep. However Barney O’Meara may have overstated the difference in blue vs. red or green LEDs.

The actual measured conversion efficiencies (light output/power input) of R, G and B are:

R = 5.9%
G = 5.0%
B = 14.3%

So the ratio of B/G is about 3.

Definitely. I recently got a raidmax case with a blue led power light-terrible. I look down and am instantly blinded. I guess I just need to find some of that green phosphor paint.

In addition, blue scatters more widely than other colors as it passes through the eyeball, Sliney said. Together, these two effects cause the intense blue light from a point source, like an LED, to spread out across the retina, interfering with other parts of the scene. It’s called dispersion: Blue’s shorter wavelength makes it refract at a greater angle than, say, red or green.

Dispersion is not the same as scattering …

Another way to dim over-bright LEDs is to tape a piece of paper over the LED. Just add layers until it’s dim enough.