Refraction is the examination of the refractive error of the eye, which is used to determine whether the refractive state of the eye needs to be corrected. Refractive examination generally includes spherical lens power, column lens power and astigmatism axis position, as follows. The first part of the refraction test is the spherical lens number, when there is a (-) sign in front of the spherical lens number, it means myopic spherical lens number; when there is a (+) sign in front of the spherical lens number, it means hyperopic spherical lens number. The second part of the refractive examination is the cylinder lenses, which are generally used to correct astigmatism, which can also be categorized into myopic astigmatism and hyperopic astigmatism. When there is a (-) sign in front of the cylinder lens degree, it means myopic cylinder lens degree; when there is a (+) sign in front of the cylinder lens degree, it means hyperopic cylinder lens degree. The third part of the refraction examination is the astigmatic axial position, which refers to the position in which the astigmatism is oriented. Different refractive errors appear on different meridians of the eye, representing the directionality of the astigmatism. Refraction examination can detect whether the human body has farsightedness, nearsightedness, as well as astigmatism and other refractive errors, if there is an abnormal vision manifestation, you should go to the medical institution as soon as possible to consult the doctor, to clarify the cause of the problem, and then comply with the doctor’s instructions, so as to avoid delays in the diagnosis and treatment.