Parameters:
1. Range of diopter measurement: From 0D to ± 20D
2. Minimum scale value: 0.125D at 0D to ± 5D, 0.25 at ± 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. Size of lens: 20MM to 80MM
7. Overall dimensions of device: 40.5*13*19.5 (CM)
8. Lighting lamp: 220V 3W/110V 3W
9. Weight: 4KGS