Parameters:
1. Range of diopter measurement: from 0D to ±20D
2. Minimum scale value: 0.125D (0D to ±5D), 0.25 (±5D to ± 20D)
3. Astigmatism axis of cylindric lens: 0 to 180°, minimum scale value 5°
4. Prism base angle: 0 to 180°, minimum scale value 5°
5. Regulation of ocular visibility: ±5D
6. Lens Size: 30mm to 90mm
7. Dimensions: 46*17*24cm
8. Weight: 7.35kgs
9. Lighting lamp: AC220V/110V 25W