Indoor ENG part 1

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LED TECHNOLOGY

Colour temperature Light is not always the same. It can be more or less white, cool or warm. The colours of objects are perceived differently, according to the type of light source used. Two very important parameters are used to classify the light sources from a qualitative viewpoint: colour temperature and chromatic rendering index. Colour temperature, which is expressed in Kelvin (K) degrees, is used to objectively identify and classify the colour of the light emitted by a lamp with respect to the sample source (black body). If we say that a lamp has a colour temperature of 3000K, we mean that at this temperature the black body will emit light of the same tone (defined as warm). A colour temperature of approximately 4000-4200K is classified as neutral and a colour temperature higher than 5200K is classified as cool.

10000K

10000K - clear blue sky

9000K 8500K - sky with haze 8000K

7000K

7000K - cloudy overcast sky

6000K 5500K - full sunlight at noon 5000K

4000K

3600K - 1 hour before sunrise/after sunset 3500K - light at the end of the day 3100K - sunrise/sunset

3000K

2900K - 100W incandescent lamp (Tg)

2000K

2650K - 40W incandescent lamp (Tg) 1900K - candlelight

The LED manufacturing process and the phosphorus application are very delicate and subject to mistakes. For this reason, manufacturers have decided to divide the chromatic areas of the various batches in different sectors (called bins) defined on the CIE chromaticity diagram. In this way, instead of changing the production systems for each different type of LEDs, it is possible to define the colour homogeneity area and classify each production batch after production.

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