TESLAbikář or how to choose the right LED bulb
Part 7 CRI or Colour Rendering Index of LED bulbs
We have already written about the effect of temperature, or the colour of light on the human body. And now, as far as colours are concerned, we will continue with CRI values. The CRI (Color Rendering Index), or Color Rendering Index, evaluates the fidelity of color perception when illuminated from an artificial source as the human eye sees it compared to how we would see it in natural sunlight. Numerical values are given in conjunction with the abbreviations CRI or Ra.
The CRI (Ra) value can be as high as 100, so we can see the colours as they really are. The light source therefore has a completely natural colour rendering. Conversely, a value of 0 tells us that we are not able to distinguish colours at all with this lighting.
RED OR BROWN APPLE
In some rooms, true colour rendering is very important. The first room that comes to mind is the kitchen or dining room. This is where we process ingredients, store fruit and vegetables and make sure everything looks fresh and appealing - after all, we eat with our eyes. So if we choose a light source with a lower CRI (Ra) for these rooms, fruit and vegetables can look bland and wilted, just like meat or cold cuts. In this case, it is definitely worth looking for an LED bulb with higher colour rendering index values. It's not just about the colours of the food, but also the fact that with low CRI (Ra) values, colours are 'sharper' and affect our overall mood, we may be more likely to feel tired and sleepy, and even spatial orientation may be worse.
WHAT IS THE STANDARD TODAY?
Most LED bulbs have a CRI (Ra) value greater than 80. Even TESLA lighting's LED bulbs have CRI (Ra) values greater than 80.
The standard CRI (Ra) value is 80. If we want to feel comfortable, we recommend this value. There are industries where colour fidelity is very important, whether it is graphic studios, galleries, jewellery shops, beauty salons or medical facilities or production lines etc., then look for LED sources with an even higher colour rendering index.
The next part will be dedicated to the lifetime and switching cycle of LED bulbs, which are in the range of TESLA lighting.
English 
Czech