Sight Tester (Spherical, Cylindrical lenses, Astigmatism axis, Cross cylinders, Rotary prisms) Specifications : Spherical lenses : +19.75D to -28.00D (0.25D steps): twin dises. Cylindrical lenses:
(w/aux) 0 to C-5.50D (0.25D steps) Astigmatism axis : 0? to 180? Cross cylinders :
Spherical, Cylindrical lenses, Astigmatism axis, Cross cylinders, Rotary prisms