The study of lighting ergonomics abroad has a relatively long history. The conclusion shows that the human eye’s perception and sensitivity of LED light effects are subtly different from traditional light sources. If you do not understand this difference, you may not be able to use the LED to bring us comfortable lighting. For example, what kind of light efficiency is more efficient? Why LED lighting has more glare?
First of all, from the human eye cells.
Human eyeballs add up to about 120 million cone and rod cells. Through rod cells, we can perceive light. Through cone cells, we can see colors.
The reason why cone cells can see the “color” is that they have three kinds of “green, red and blue” cells. With the RGB primary colors, we can see all the colors including white. However, there is only one kind of rod cells, so the color cannot be seen.
What needs to be corrected is that the so-called “red cones,” “green cones,” and “blue cones,” just mentioned, are inaccurate. The cells themselves do not have these colors, but they are just for red light. Green and blue light sensitive.
Red, green and blue are long wave, medium wave, and short wave, respectively, so they can be called L, M, S cells. For example, red sensitive cones, which can be called L-cones or long-wave cones, represent long wavelengths. Short-wave cone cells are blue light-sensitive cone cells, officially called S-cones. Green light-sensitive cone cells are called M-cones and represent medium-wave cone cells.
In addition, the degree of activity of cone cells and rod cells depends on the strength of light. If the illumination level is high, the cone cells work efficiently, and the rod cells are very inactive. When the illumination is very low and very dark, the cones are not active. Therefore, under very dark conditions, we use rod cells to observe and see only black and white and no other colors in the line of sight. We will have data later to illustrate this point.
