Many students buy weaker and weaker ‘reduced’ eyeglass prescriptions for driving… as their sight is improving with practice of Natural Eyesight Improvement.
Buying on-line, filling in your next lower prescription gives people the option of a lower price while maintaining high quality. I like Zenni Optical.

Students have asked me why their doctor did not write the P.D. on their prescription. Without the P.D. the optical stores cannot create a prescription. P.D. = placement of the eyeglass lenses in the frames, frame size to get the left and right lenses centered exact in front of the eye pupils. This must be done correct or the glasses will cause more vision impairment.

Above is a picture showing how to test for your P.D. It’s best to get a doctor to do this but you can also check the doctors number this way. It changes for close and far distances so using a mirror, doing it yourself is not always exact. I will add entire directions soon. Go to zenni-optical on the Internet and other optical businesses for more pictures, directions for P.D and other numbers on the prescription form. Zenni will help a Natural Vision Student get the correct prescription.
I learned some of this from Penn Foster Optical College. Had to quit college when found out have to spend one year as intern working free at an optical factory which is 20 miles from any transportation, so have to wait. They teach many helpful things and I will return to the course and factory when I buy a new truck.