LEDs

[CloudHands]

Leds emit is actually pure blue light through a layer of phosphor which produce a wider light spectrum. Has that thin layer a durability comparable to the chip ? I hardly find information about that.

More generally, what do you think about LEDs ?

[Marblehead]

I have a few LEDs around the place, mostly outside.  Very energy efficient.  Mine are all 12VDC.  I'm not yet impressed with the 120VAC LEDs.

 

 

[Kar3n]

I am unimpressed with the claim that they last for years. It is not the case in my house.

 

On a side note, when I saw the title of the topic my first thought was, "Oh Lord, not another mo pai thread!"

[CloudHands]

46 minutes ago, Kar3n said:

I am unimpressed with the claim that they last for years. It is not the case in my house.

 

On a side note, when I saw the title of the topic my first thought was, "Oh Lord, not another mo pai thread!"

 

John Chan did light up leds too ?!

[9th]

 

[vonkrankenhaus]

Here is the "John Chang" version:

 

https://www.amazon.com/Copernicus-Human-Powered-Light-Bulb/dp/B001EVK3F6

 

 

 

 

 

-VonKrankenhaus

[CloudHands]

My concern towards the durability of the phosphor layer is that blue light is harmful to the skin and the eyes and modify the circadian rhythm.

Blue is a frequency (450−495 nm), it gives your body an information.

Phosphor helps providing a wider spectrum yet a blue dominance remain.

https://en.wikipedia.org/wiki/Light-emitting_diode#/media/File:White_LED.png

 

https://en.wikipedia.org/wiki/Incandescent_light_bulb#/media/File:Spectral_power_distribution_of_a_25_W_incandescent_light_bulb.png

 

I have been testing them lately and once you put attention on it and compare different kinds of lamps I feel light coming from LEDs cold and uncomfortable. The 2700 kelvins feels OK as a coloration but it doesn't provide a warm feeling as light generally provides.

When you receive light from the sun, you receive light and heat. Wood fire too, a candle too. With these old bulbs too. Not with leds : the minimal heat coming from a led is not from a lighting process but induced by a driver transforming electricity.

 

Maybe it's just because I'm used to heat dissipation maybe it's because I associate blue with death but I have definitely a preference for the incandescent lights. I'm ok to use them but not anywhere anytime... Not in my room, not close range and certainly not before sleeping. Now about long term health effects, psychological effects, as we are testers nobody knows. Probably nothing critical for health, just another slight separation from nature.  

 

[CloudHands]

This is sunlight spectrum a sea level.

 

https://upload.wikimedia.org/wikipedia/commons/2/27/Spectrum_of_Sunlight_en.svg

[CloudHands]

http://www.dailymail.co.uk/health/article-2470513/Lights-effect-sleep-suggested-new-research.html

[windwalker]

edited 

 

Edited November 1, 2017 by windwalker

[cheya]

Hey CloudHands,

I've studied the health effects of light quite a bit, and that article from the Daily Mail is an excellent summary of the most important facts and precautions. Thank you!

[CloudHands]

You're very welcome Cheya