Generally, the illumination of the study room is 100Lux, but the illumination required for reading is 600Lux, so it is best to use a desk lamp as local illumination. I can only distinguish the outline of a face indoors. The illumination is 20LX, and the illumination for playing chess and cards is 150LX. It takes about 250LX to read novels, that is, 25W incandescent lamp is 30-50cm away from books, and 500LX to write, that is, 40W incandescent lamp is 30-50cm away from books, and it takes about 30LX to watch TV. Just put it out of sight with a small 3W lamp. Maintaining proper illumination is of great benefit to improving the efficiency of work and study; Working and studying in too strong or too dark light is harmful to the eyes.