Interesting read on LED Lighting

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Itsme
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Interesting read on LED Lighting

Looks like the high CRI LEDs may have more benefits than just a nice tint.

Thoughts

https://returntonow.net/2017/11/15/dark-side-led-lighting/

smalljiang
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Good article, but I can’t fully agree that.Any strong light source will cause certain damage to the vision,including sun light,fluorescent light,LED light.But that not mean incandescent bulbs is totally a good choice.
Due to inefficiency of incandescent lamp,to save energy,people usually tend to use light with low power(below 60W).This makes the area where it is effectively illuminated is very small,and its illumination is very low,.So slightly farther away from the light will not meet the needs of people working normally.For example, the illuminance on the working plane of the precision assembly should be above 400Lux, so that the eyesight will not be damaged.
Because the filament sublimates, the incandescent light decay quickly and not bright enough, then the illumination on the working plane will drop sharply at this time,if you used for a long time, it will also damage the eyesight.
At least LED light can save energy, friendly to environment.

djozz
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That article is pretty much crap, the factual background is nothing more than that cool white light in the evening makes you fall asleep a bit less well (the melatonin story which has indeed a scientific background), but this guy expands that with additional theories of life-threatening proportions . There's insinuations of getting cancer from blue light which is rather farfetched and very indirect, and the author's theory that blue light must be 'balanced' by enough near-infrared light is based on completely nothing, it is nothing more than a clumpsy argumentation to make 'natural' sunlight which has a huge blue and UV component better for your health than 'artificial' ledlight.

 

When I was really dropping out is when he shows the spectra of cool and warm leds, what he shows as a warm white led is a really ugly example peaking at 560nm, while for example warm white XM-L2's have a rather different spectrum peaking at 610nm. I guess that he spend quite some time to get the coolest 'warm white' spectrum he could find.

 

From the article of the OP:

 

From the XM-L2 datasheet:

mdeni
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Lights with +4000K should be illegal.

They are uglyfuing all nice cities, and all nice homes.

djozz
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mdeni wrote:
Lights with +4000K should be illegal.

They are uglyfuing all nice cities, and all nice homes.


Party I do agree with that, I like the warm glow of the incandescent days Smile
mdeni
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djozz wrote:
mdeni wrote:
Lights with +4000K should be illegal.

They are uglyfuing all nice cities, and all nice homes.


Party I do agree with that, I like the warm glow of the incandescent days Smile

I would even make a multiple led bulb with high CRI, and a few 660nm deep reds, and 500nm teals.

I can’t seem to find N219 9080.