Optometry usually only requires selecting a reliable one at a nearby eyewear shop. The parameters of machine optometry are for reference only, and more importantly, subjective optometry involves inserting lenses for trial wear and then adjusting the lens of discount glasses degree based on your subjective feelings.

After selecting a store for lens production, the first step is to ask customer service what optometry parameters are required. Generally, the basic parameters include

1) The spherical diopter of the left and right eyes (i.e. the degree of myopia for most people and the degree of farsightedness for a small number of people)

2) Columnar diopter (also known as astigmatism)

3) Astigmatic axis position

4) Pupil distance (also known as PD, note that there may be differences in left and right pupil distances)

5) Single-eye corrected vision (try to have a consistent corrected vision in both eyes)

If there is no astigmatism, generally only the two data of spherical lens degree and pupil distance are needed. When going for offline optometry, be sure to wear old discount prescription glasses. Old glasses are similar to your case, and optometrists usually ask you for old glasses to understand the original glasses' data. Based on your feelings about old glasses and current needs, optometrists can provide the most suitable glasses advice.

After the X-ray examination, the optometrist will issue a prescription for glasses. You can take a photo of this prescription and send it to customer service for confirmation.