Jump to content
Science Forums

Recommended Posts

Posted

When we work for long hours under a CFL Lamp, it weakens our eyes and affects our health. It contains toxic substances like mercury which can lead to cancer. Guess its time for us to replace CFL bulbs forLEDs

Posted

Light Emitting Diodes generally only produce a very narrow spectrum of light.

 

If they made a large array of multiple types, maby, but right now the gas mixture used produces a much wider spectrum, which is 'easyer' on the eyes IMO.

Posted
Light Emitting Diodes generally only produce a very narrow spectrum of light.

 

If they made a large array of multiple types, maby, but right now the gas mixture used produces a much wider spectrum, which is 'easyer' on the eyes IMO.

 

Ditto on my last post.

Posted

No matter what the spectrum of the light, if the object is red it emits red wavelenght if its green it emits in green. Although diffrent collors might look diffrent under diffrent types of light.

 

The problem is either overillumination or light flicker. Thats the problem with CFLs, they emit some UV light and the old ones flicker at 100Hz. But newer and more efficient use electronic ballasts which have a frequency of about 20kHz, so flicker cannot be sensed with ordinary methods.

 

I would love to see more LEDs, couse I have a flashlight that has one and its bright as the sun. :) But CFLs are just as good for the time being.

Posted
No matter what the spectrum of the light, if the object is red it emits red wavelenght if its green it emits in green. Although diffrent collors might look diffrent under diffrent types of light.

 

Sorry, Bud, I think you should research color a bit. Specially the color of objects.

Posted

The LED lights are still quite expensive but have many advantages. They have an extremely long life in the range of 50-100K hours, and give off the most light energy for any given amount of energy input. They run cool, but do require a heat sink.

 

LED's can be tailored to specific wavelengths or can be made in white. The current trend is to make larger lights using many small LED bulbs, each in the range of 0.25-2 watts, with the higher end more efficient but more expensive. So if you need 20 watts, an LED light might be be composed of 80-10 light emitting diodes. The better lights also uses little lens on each diode, to focus the angle of the light for spot or diffuse effects.

 

One possible future application, which is already in use, is home stage lighting effects, where an area is lighted with separate R,G, and B, to create vivid colors. Turning the dinner party into a colorful theater affect would be the lighting equivalent of surround sound, which can be adjusted for ambience.

  • 5 months later...
Posted
When we work for long hours under a CFL Lamp, it weakens our eyes and affects our health. It contains toxic substances like mercury which can lead to cancer. Guess its time for us to replace CFL bulbs forLEDs

I have years to wait for the CFLs that I put in this year to explode.

But yes, LEDs are the future. They will enable us to turn our sterile, concrete cave/malls into tropical forests and re-connect our office workers with nature as we fill these spaces with the trillion plants we need there.

 

The the eye-piercing brightness is a problem for some and more mellow light needs to be developed.

  • 1 month later...
Posted

So the question is are LED's a good idea? guys, try Googling LED Lightbulbs....eg. a 7.5W LED Lightbulb is the equvalent of a 60W Incandescent, and they last 40x the life of a incandescent. Cost? WELLL that's something of a different topic (they are more expensive)...

 

HOWEVER....would LED lightbulbs be easier on the eyes? Well I dont know since I dont have any, but my guess is that they would be.

 

-----------------------

Posted

So far my experience with LEDs has been somewhat less than ideal. The spectrum is far to narrow, the bulbs they sell are not as bright as advertised and the things are outrageously expensive.

Posted

I would have to agree with Moontanman. I even have an LED headlamp for camping. The light takes a bit getting used to. The illumination is not what I would expect. I am wondering if the narrow visible light band leads to seeing difficulties, or if the rated output includes invisible parts of the spectrum or nearly invisible parts of the spectrum such as long reds near the infrared end of the visible spectrum.

Posted

They are quite a bit more expensive than incandescents or CFL, but they are coming down in price.

 

This company claims to have developed a LED array that delivers full spectrum light, or any K rating desired (within limits).

 

Full Spectrum LED Grow Light

 

LEDs seem to be a great idea in the long run, but I agree that they are currently too expensive, despite their longevity.

Posted

What's the pollution footprint of the LED production process? It doesn't help that they use a lot less energy than normal bulbs, last ten times as long, but produces ten times the pollution in production.

 

So - anybody know?

Posted

 

LEDs seem to be a great idea in the long run, but I agree that they are currently too expensive, despite their longevity.

There was an interesting discussion of these in a Poll thread "How many Indoor Plants do Hypographer's Grow" or similar. I can't find it so may have the name wrong

There is a good link to a Chinese manufacturer of LEDs in a post by HB.

 

You could go to the electrical shop, buy a stack of different spectrum leds, and knock a light up yourself?

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...