Reminder of the different ways to get a white light with an led.
-1: combine an LED emitting a short wavelength (in blue) with a yellow phosphor, phosphorus generally.
-2: combine an LED emitting in the ultraviolet close coupled to one or more phosphors.
-3: combining at least three LEDs emitting visible wavelengths which combine to give a white light, generally red + green + blue.
The method most used to get a white light colour remains method n ° 1 because it is the most economical to produce, it represents almost all of the led lights that can be found in a led light bulb a few are manufacturers, such as LEDBulbBay.com.
Reminder of some technical terms.
The lumen is the unit used to quantify the luminous flux, it expresses the total quantity of light emitted by a light source.
The candela is the unit used to express the quantity of light emitted in a given direction.
Finally, the Lux determines the amount of light on a surface.
Definition of the classification of the level of risk defined by the standard NF EN 62471 of security biological picture that defines 4 groups of risks.
The Group of risk 0 (risk-free), the product is harmless biological photo.
The Group of risk 1 (low risk), the product does not present a risk to exposure limits to normal operating condition.
The Group of risk 2 (moderate risk), the product does not present a risk to the response of aversion due to thermal discomfort or very bright light sources.
The group risk 3 (high risk), the product may pose a risk even for a short or momentary exposure.
The standard NF EN 62 471 provides an assessment of the risk to the distance at which a group or several LEDs produce an illuminance of 500 Lux. An angle of diffusion of the led so strongly decreases the risk since the illuminance decreases with distance from the source.
More the opening angle is important and more luminance measured in Lux will be weak in moving away from the source.
Bulb – leds.fr was the first company in France to offer lighting at 360 ° in 2007 and led bulbs gu10 with high angle between 80 and 140 ° reducing this risk due to glare in order not to focus the luminous flux on a small surface.
The ANSES report describes 2 main risks in its report
-The risk associated with blue light, either pure blue lighting (Royal Blue) or cold white lighting to in K 5200 ° dessou.
-The risk associated with glare.
According to this report and according to the many questions from users who challenge us that it does not sufficiently if the risk is present only as part of a blue light obtained from a led-based lighting source or if it is a generality of blue lighting a few either the source used. Greater precision would have been useful, or so the public has failed to understand this risk generated by blue light.