... : 0.0 to -29.50 Diopters, step: 0.12,0.25,0.50,1,3 0.00 to +26.75 Diopters, step: 0.2,0.25,0.5,1,3 Cylinder: 0.0 to ± 8 ... : -20 to +20, step:0.1,0.5,20Prism form: Base up,base down,base in,base out Near distance: Mechanical converging with an ... optical axis at 40 to 67 in front of eyeBinocular balance: Rotary prism,polarizing filter and R & G filterCross cylinder: ±0 ...