Due to the characteristic of presbyopia, the eye has poor ability to regulate distance and proximity. For example, when the user's visual diopter is+4.00D (commonly known as 400 degrees), their visual adjustment ability can only function within a few centimeters. A pair of reading glasses only adds a fixed diopter to the user's vision, and does not enhance the user's visual adjustment ability. That is to say, users are not necessarily required to wear a fixed degree of reading glasses, but should choose the appropriate degree of reading glasses based on the distance of their own visual acuity