Sunday, January 23, 2011


(Please read this article from Scientific American (Jan 15, 2010) and leave your thoughts as a comment, a couple of sentences)

Building a Better Light Bulb

The race is on to develop the modern light bulb, but it may be that the modern light bulb won't be a bulb.

Incandescents -- The Old Standard Bearer

Since the days of Thomas Edison, the incandescent light bulb has been the king of illumination. It works on a basic principle of physics: the hotter a body is, the more light it radiates.
In an incandescent light bulb electrons are forced through a filament to make it so hot that it glows. Because so much of the electrical current's energy goes into heating the filament, incandescent bulbs tend to be very inefficient. And so, acting on today's low-carbon imperative, many people are looking to replace the incandescent with something more efficient.
Others have not yet given up on the incandescent and are working to make that 19th century lighting technology as efficient as its rivals -- the compact fluorescent light (CFL) and light-emitting diode (LED) (both described here).

CFLs -- The (Relatively) New Kid on the Block

Seemingly poised to replace the incandescent, CFLs work on the basis of fluorescence instead of incandescence.
A beam of electrons is sent through a gas causing the electrons in that gas to be excited from their ground, low-energy state to a higher energy state. When the electrons relax back to their ground state, the extra energy is released as light via a photochemical reaction.
Because fluorescence does not depend on heating the gas, CFLs are more efficient than incandescents; typically CFLs use about 75 percent less energy to produce the same amount of light as an incandescent.

LEDs -- Closing Fast

But there are people out there who don't like CFLs -- they don't care for the light quality, the flicker, and the fact that they usemercury. Not to worry; there's an up-and-coming alternative -- commonly referred to by its three-letter moniker LED.
LEDs work on the same fluorescence principle as CFLs but with a twist. Instead of sending a current through a gas, LEDs make use of a crystal semiconductor with varying properties from one end to the other (hence the term diode). Electrons on one end of the diode tend to be in a high-energy state and at the other a low-energy state. When exposed to a current, electrons flow from the semiconductor's high-energy end to its low-energy end, and the energy change shows up as light.
typical LED is slightly more efficient than a CFL, and has the added advantages of a much longer life expectancy and no mercury. That's why many experts believe that while CFLs may be a temporary replacement for the incandescent, the future of illumination will more likely belong to LEDs.

Not So Fast, Mr. LED

While LEDs may eventually win the illumination race, they are nowhere close to the finish line. They're expensive, and the light they give off can be harsh (although advances may have already made some complaints in this area a thing of the past). But still, in terms of giving either incandescents or CFLs a run for the money, LEDs seem relegated so far to primarily flashlights, where long life and low power requirements are at a premium, and outdoor applications, where the harshness of the light is not an issue.

Snow Blind

While we're on the subject of LEDs, here's something folks had not anticipated: LEDs don't work in the snow.
Because incandescents generate heat, they can melt away any snow or ice that might land on them. But the small amount of heat from LEDs means that when they are outside in snowy conditions, they might well get buried. Is this a problem? Potentially yes, since LEDs are being deployed in traffic signals in no small number across the country.
Earlier this month, Joanna Bush of the Department of Transportation in Wisconsin, which has transitioned 90 percent of its state-owned signal lights to LEDs, admitted that "we certainly do see crashes and accidents [during snow storms] attributed to the fact that people can't see the heads," referring to the blocked colored lenses of a traffic signal.
In her view, though, the problem of snow accumulation on the traffic signals "isn't enough to convince us to move over from LEDs."
So while the world awaits a high-tech solution to the problem of snow-obscured LED traffic lights, Wisconsin's DOT, not wanting to sweep the potentially serious problem under the rug, has its own quick fix: "dispatch workers with brooms to clear the lenses." The 21st century meets Disney's The Sorcerer's Apprentice?

Feel the Glow

It could turn out that the next illumination king could be none of these three.
A Welsh company called Lomox is working on a technology based on organic LEDs that would cause walls that are coated with the product and charged with a low-voltage current to glow.
The company claims that its technology will be two and a half times more efficient than the best bulbs available today and will illuminate a dimmer-equipped room in much the way sunlight brightens a room.
Cool. Can't you just see it: Ten years from now, you sit down with your e-reader in your dark room on a snowy winter night and command a robotic broom first to switch on the wall and then to go outside and sweep off the yard lights.

(I found the article by going to the Scientific American website and searching "light bulb")


callgire11 said...

I believe if the new light bulbs that are being invented now than we should use them. However, the light bulbs we use now work fine and so I do not have a problem with this kind.

Cadyladyy said...

welll i just wanted to say that i have LED light bulbs in my room and they really make a difference. they take a few minutes to warm up and i think that they can really make a difference in the economy. They are rather expensive though

Kaitlin said...

Ok so i just want to say that i think that lightbulbs that we use now are fine so why do we need LED? First off the cost so much more and secondly they don't really make a difference in my house. I think that buying LED lights are a waste of money.

Becca said...

I have lights in my room that take a little longer to get bright but they last longer then regular lightbulbs. However, I dont see a problem with the regular lightbulbs we have today. I think its all based on preference for what people want to use but I think they are both good and people can make their choice on lightbulbs. I see nothing wrong either choice.

akastor11 said...

My opinion on LED light bulbs are that they may be more efficient, but since they are much more expensive it will take more time for more people to start buying them. They also take a longer time to get bright and light bulbs used today work very well. The energy saving is more of an issue relating to regular light bulbs but i think over time someone will invent a faster less expensive LED.

Cwatkins#7 said...

when buying a light bulb i would normally just buy the cheaper one but if i were forced to choose after ready this article i would choose the new led lights just because they are much brighter and allow me to see things at a greater depth.

Ken said...

I think LED lights are just another invention conveyed as a updated product for money. They take longer to light up, and really dont give a major lighting difference. Companies are just trying to persuade consumers to buy the best and new product. However in this case I dont believe its the best. I prefer regular lightbulbs, and I think it will take a long time to have a universal change.

Candace said...

i think that the regular light bulbs we use now are fine. My family usess incandescent and we dont have any problems. sure every now and then one blows and we need to replace, but they are cheaper than LED. i dont like the color or look of LED ones so i think its dumb to use those ones.

tkuppe said...

I honestly hope that LED's become outdated, and eventually extinct. Not only are they expensive, but inside... They flat out suck! We tried LED's for a table lamp, and the light was near blinding. Like the article said, outside, or flashlights. I was honestly shocked to see LED's don't work in the snow, seeing as cars with LED headlights work perfectly fine in the winter months. I'm iffy on what Joanna Bush said, because it's discussing signal lights, and the quote is about cross walks. It be safe to say, at least in my opinion, LED's work fine as headlights. The organic LED is a spam to get you to buy the light, and the product to coat the wall with for the glow.And why would there be a robotic broom, it was a really odd placement for that worthless bit...

c gatt22 said...

I believe we need to find a safe alternative that is much more efficient than the Incandescents counter part. Today things have changed from what they were before we need to find energy efficient sources even if that means we spend more money. We need to make these changes for the better for the enviroment. The only problem i have with the LEDs is they are pretty much blinding in headlights and are not very reliable so the only thing we can hope is they changed somethign aboutthem. The conventional lightbuld flatout just wastes too much enery and is not efficient and needs to be replace with somethign better.

Reesman22 said...

My preferred method of lighting are CFLs because of the energy they save but the quality is awful. LEDs are good for flashlights....but thats all. For no reason should they be used in car lights, let alone on roads. The original light bulbs work fine but they don't last extremely long. So in conclusion, most types of light sources have flaws but a "cure" doesn't seem to be in sight. The preferable thing to have would be a bulb that gives good, stable light that lasts a long time, uses little energy, and doesn't take a large toll on the environment. Most importantly it has to be cost friendly. Hopefully someone will make these soon but thats probably only a pipe dream.

Allison Baby. said...

I think the LED lights that they are working on will be a great advacement to future technology. I believe the fact that it could be a whole wall will increase visual contact.

Bonjour Lindsey said...

I personally dont really see the use for LED lights. I am perfectly content with the light bulbs my family has in our house. Though, recently we put two LED lights above our table in our kitchen and its annoying when its dark and you go to turn on those lights and they take a while to light up. I just dont see why we cant stick with the light bulbs we have. They work and their not expensive. I guess its just what people prefer.

Bo$$ said...

i have no problem with the old lightbulbs but i could just be biased because those are the ones that i have in my house. the new ones may be more eco-friendly but i have to say trhat they do not look as nice and are ugly. in the future the newer bulbs will probably take over and work out for the better but for now i have no problem with the old bulbs.

Ryan Ackim said...

As of right now I do not have a problem with the older light bulbs. I did an experiment and found out that there are way more of the older light bulbs in my house than the newer ones. However, I am guessing that in the near future the look of light bulbs will be changed to the newer ones. The look will change because the newer light bulbs are way more eco-friendly and will drive the older bulbs to extinction.

Matt said...

Led lights do have their purposes. they are more economical and effecient to use. but their downfall is that they are rather expensive. also they take longer to light up when its cold. so i am indifferent to led lights, they can be useful but also a pain.

Lexi said...

Ok well i guess it depends on how you want to use the lightbulbs. LED bulbs are great for the economy and they last longer, but the regular light bulbs we have now work fine in my opinion. They last long and they're not that much more expensive than LED bulbs.