The letters L and R stand for left and right respectively, L is the abbreviation for left and R is the abbreviation for right, the Chinese translation of left is left and right is right. So L stands for left and R stands for right, and can be distinguished in this way. If you still can’t tell the difference, you can refer to the contact lens prescription and compare it with your own. If the contact lenses are 300 degrees and 500 degrees, the left eye is 300 degrees, then 300 degrees. If the left eye is 300 diopters, the 300 diopters will be in the left eye, and if the right eye is 500 diopters, the 500 diopters of the contact lens will be worn in the right eye, so you can differentiate in this way. Children’s corneal reshaping lenses are often color-coded, and you can rely on the harmonics, “blue” left, “green” right, to distinguish between left and right eye wear. Since keratoconus lenses do not have a prescription but only a model, and the model may be difficult for many people to distinguish, you can rely on the color to differentiate between the left and right eyes.