英国《每日邮报》最近报道，最新研究表明，LED节能灯有可能对人们的视力造成损害

据英国《每日邮报》最近的报道，西班牙一项最新研究结果表明，LED节能灯有可能对人们的视力造成损害。研究专家认为，台灯等近距离使用的灯具尽量不要使用LED灯泡。背景知识：

Blue light

Blue light hazard is defined as the potential for a photochemical induced retinal injury resulting

from radiation exposure at wavelengths primarily between 400 nm and 500 nm. For the purposes of this discussion, blue light is defined as light within the wavelength range of 400-480 nm, because over 88% of the risk of photo-oxidative damage to the retina

from fluorescent lamps (cool white or ‘broad spectrum”) is due to light wavelengths in the

range of 400-480 nm. The blue light hazard peaks at 440 nm, and falls to 80% of peak at

460 and 415 nm. In contrast, green light of 500 nm is only one-tenth as hazardous to the retina than blue light with a wavelength of 440 nm. The mechanisms for photochemical induced

retinal injury are caused by the absorption of light by photoreceptors in the eye.

Under normal conditions when light hits a photoreceptor, the cell bleaches and becomes

useless until it has recovered through a metabolic process called the “visual cycle.

Absorption of blue light, however, has been shown to cause a reversal of the process

where cells become unbleached and responsive again to light before it is ready. This greatly

increases the potential for oxidative damage. By this mechanism, some biological tissues such as skin, the lens of the eye, and in particular the retina may show irreversible changes induced by prolonged exposure to moderate levels of UV radiation and short-wavelength light.

According to some of these studies, blue light waves may be especially toxic to those of us

who are prone to macular problems due to genetics, nutrition, environment, health habits,

and aging.

At present, LED to achieve white light, there are three main methods:

  1, the LED of the three primary color chips red, green and blue multi-chip group and synthesis of white light.

                                                                                       

   Advantages:                                                                                                                           

- high efficiency,

- color temperature controllable,

- better CRI

   Disadvantages: three primary colors decay caused by different color temperature instability. The control circuit is more complex and costly.

2, the yellow phosphor excited by blue LED chip and a phosphor emitted white light yellow-green synthesis

Advantages:                                                                           

- high efficiency,

- simple preparation,

- temperature stability,

- good CRI

   Disadvantages: poor consistency, color temperature variation with angle

3, excite phosphor emit ultraviolet LED chip synthesis tricolor white

Advantages: the CRI is good, simple preparation

   Disadvantages: currently, LED chips efficiency is low, a UV light leakage, and the phosphor

temperature stability problems to be solved

In the currently technical conditions, with the first two methods to the white LED, if you want to continue to improve the efficiency of LED light, LED chip manufacturers have to increase the proportion of blue in the chip. Especially, when the color temperature is greater than 4000K.

Therefore, it is true that LED lighting products bring the blue light than conventional lighting products much higher chance of hazard.



As a responsible lighting company on this issue to be addressed at the application stage that the color temperature is greater than 4000K LED lighting products in the chimney wall add a layer of blue paint filter, or to be added directly into the shade of this material within the material, so that blue light risk problem can be solved. Doing so is a direct consequence lead to a decline in efficiency light. Therefore, the currently market, we fins than many respectable companies luminous efficiency of LED lighting products is only 50-60lm/W. while there are many other companies it have claimed more than 100lm/w.

Is their technology beyond the former? The answer is clearly NO.



As ordinary consumers, we can try use the advice given is not greater than 4000K color temperature of LED lighting products and buy your courage to take responsibility for that company’s products. Not one-side pursuit of high luminous efficiency.
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