Projection chart is not allowed.

Size, brightness and other reasons. The results of screen projection may be affected by many factors, such as the resolution of computer screen, the size of display, brightness contrast and surrounding illumination, which will have a certain impact on human vision, thus affecting the accuracy of test results. Projection eye chart can only measure hyperopia, but can't detect myopia, astigmatism and other common ophthalmic problems, and can't completely replace traditional vision detection methods.