Why are the pictures of text files taken by the Xiaomi smartphone fuzzy?

Different lenses have different minimum focusing distances, which is normal. When you use the main camera beyond the minimum focusing distance, the camera system will automatically switch to ultra-wide angle to shoot (adaptive lens is turned on by default in the camera settings) to ensure focus. At this time, the picture is a cropped picture of the ultra-wide angle, and there will be a certain loss of pixels, so the clarity will be lower than that of the main camera.