... to ±20D: 0D, ±1D, ±2D, ±3D, ±4D, ±6D, ±8D, ±10D, ±15D, ±20D.5. Aperture wheel: red-free filter, Large spot, small ... : =85 lxDiopter: 0D, ±1D, ±2D, ±3D, ±4D, ±6D, ±8D, ±10D, ±15D, ±20DAperture: red-free filter, Large spot, small spot, hemispotRated voltage ...