Patients can determine the degree of myopia and astigmatism through computerized optometry, and if contact lenses are required, the astigmatism can be converted to myopia. Myopia and astigmatism can be computerized to produce a specific degree of myopia. If the patient’s right eye test result is S:-200, C:-150 x 60, it means that the patient’s right eye is 200 degrees of myopia, 150 degrees of myopic astigmatism, and the astigmatic axis is at 60 degrees. Myopia is generally not converted to astigmatism, but astigmatism can be converted to myopia, which applies to contact lens wearers to calculate the prescription. This is usually done by dividing the amount of astigmatism by two and adding it to the amount of myopia, as in the example above, so that the patient’s myopia becomes 275 diopters, which can be used for contact lens wear. However, this method is not absolutely accurate, and the patient can choose the right prescription by trying on the glasses. It is recommended that patients with refractive errors seek prompt medical attention to evaluate their condition and follow the doctor’s instructions for treatment.