Measurement and judgment of pupillary distance and optical center distance of glasses were discussed. Comparing the advantages and disadvantages of pupil distance rulers and pupil distance meters from the perspectives of operational difficulty, measurement accuracy, resolution and cost, pupil distance meters would be the better choice. Combining relevant statistical data and examples to illustrate that spectacles using monocular pupillary distance had better visual correction. Measurement methods and notes of the optical center distance were introduced. The uncertainty of optical center horizontal distance measured with a ruler or caliper was evaluated, and the influence of uncertainty on compliance determination results was analyzed.