1. Match the red and green sights with a spherical mirror and quantify the degree of the spherical mirror. The red color code is also clear and bright, indicating that the tested eyes have the best vision whether they wear glasses or not. The green area is clear and bright, indicating that myopia correction is high and hyperopia correction is insufficient. The red area is clear and bright, indicating that myopia correction is insufficient and hyperopia correction is high.

2. The binocular balanced polarization sight is equipped with a polarizer and a spherical lens, and the binocular test is carried out to quantify the refractive balance of both eyes.

3. Visual standard of X-ray astigmatism When the eyes with corrective glasses or without glasses look at the astigmatism table with uniform thickness in all directions, it is proved that the astigmatism of the examined eye has been completely corrected or shows no astigmatism. When the examined eye finds a line in the astigmatism table that is black and clear, it indicates the possibility of astigmatism.

4. The point astigmatism sight is equipped with a cross cylindrical mirror and a cylindrical mirror, and the monocular test is carried out to quantify the astigmatism axis and astigmatism.