5.0 is the standard visual acuity, which is normal, but it cannot be said that the eyes do not have the degree, because the human eyes can be adjusted, the small degree, usually within 50 degrees, some people can adjust to achieve the standard visual acuity of 5.0. The eyes, especially the ciliary muscle, can change the refractive power through contraction, through refractive adjustment, small degree can also be corrected to normal visual acuity of 5.0. If you can see 5.0 at the time of the physical examination, but you are straining or have a blurry feeling, further refractive examinations are recommended to rule out any small diopters. Overall 5.0 is standard vision, which means that you can use your eyes normally, but it cannot be ruled out that there is definitely no prescription.