Cloud measuring pupil distance (patent: a method for measuring pupil distance -20 1 10207934.9): put a credit card on your forehead, take a photo, and then send it to the cloud to measure pupil distance.
Measurement number (patent: optometry table ZL 201320411077.9): accurate, convenient and fast.
Astigmatism measurement (patent: bichromatic axial astigmatism table and astigmatism measurement method using this bichromatic axial astigmatism table -20 14 10047800.9): red and green bichromatic astigmatism measurement is accurate and convenient.