In fact, the placement of the table lamp is also particular, the table lamp should be placed on the left, which is conducive to our use, and can also avoid shadow parts when irradiating. Secondly, the height of the table lamp should be lower, which can avoid the dizziness caused by the light hitting our eyes. But not too low, so that the light exposure range will be smaller, and the eyes will be more laborious to see things. Therefore, when using a desk lamp, the eyes should be kept 0.4 meters apart from the plane of the table lamp, and the height of the table lamp and the table should be 0.4 to 0.6 meters.
 
1. The height of the desk lamp is very important

Usually, when the eyes are 30 cm away from the book, they can see the handwriting clearly and will not be overly tired, so it is calculated that the height of the desk lamp is 40-50 cm away from the book, which ensures sufficient reading lighting and the surrounding environment has a certain brightness. If the lamp is too low, the light will shine too small, and the surroundings will be dark. The loss of a reference object for distant vision will make the eye adjustment system in a tense compression state that only looks close, which is easy to fatigue the eyes and accumulate rapidly, resulting in "light source myopia". And if the desk lamp is too high, the light will directly hit our eyes, resulting in glare; At the same time, strong light at close range can also cause light retention on the retina, which will tighten the eye muscles and accelerate vision loss.
 
2. The size of the bulb used in the table lamp should match the lampshade

Make sure that the bulb is exactly inside the lampshade to avoid direct light hitting our eyes.
 
3. The degree of the bulb used in the desk lamp should be appropriate.

If the degree is too low, the light shining on the book is dark, and it is not easy for us to see the handwriting, which will cause eye fatigue and myopia over time. If the bulb is too high, too strong light will be reflected into our eyes through the white paper, resulting in glare, so that the pupil continues to shrink, and then cause eye pain and headaches. Generally speaking, 25 watt-45 watts of incandescent lamp brightness is the most suitable.