So far, there is no reliable online optometry technology that can perform accurate optometry. Only offline optometry is allowed, and accurate optometry prescriptions can be obtained before eyeglass online can be arranged.

The prescription for optometry is based on eyeglasses online, and the data obtained solely through computer optometry is inaccurate. Even the most precise computer optometry instrument has errors (the human eye has a large adjustment ability, and the machine needs further improvement). In addition, computer optometry only measures the degree of a single eye separately.

We all use binocular vision (the image angles seen by the left and right eyes are slightly different, and through brain processing, we can have a more three-dimensional and realistic vision), and what we need is the best visual effect of binocular matching. Therefore, we need to carefully confirm through a comprehensive optometry device to obtain an accurate prescription for discount prescription glasses. At present, conclusions drawn directly from computer optometry measurements ignore the issue of binocular coordination and are inaccurate.

The parameters determined solely by inserting and trying on without a comprehensive optometer are unreliable. The above has shown that the values measured by a single eye cannot achieve a more three-dimensional and realistic correction effect.

Another situation is that during the insertion trial, many optometrists ignore and let the examinee determine which value is more suitable, which is very irresponsible. If myopia is accompanied by astigmatism, how to find the best astigmatism value to match the luminosity to achieve the best comfort?

It requires experienced optometrists to repeatedly compare and determine. Moreover, the accurate grasp of the astigmatism axis is not something that the examinee can do on their own.