Elegant design butterfly-shape appearance, High-grade plated-film used in all optic lenses.
This device is applicable to the ophthalmology department of hospitals and spectacle store for precision measurement of visual functions such as myopia, hyperopia, astigmatism, eyesight balance, heterophoria, stereoscopic vision and eyesight amalgamation.
Specification:
Sphere Power Range: +16.75D to 19.00D w/minimum reading 0.25D or 0.12D (when using +0.12D auxiliary lens or optional±0.12D lens)
Cylinder Power Range: 0 to -6.00D, w/minimum reading 0.25D or 0.12D (auxiliary lens), 0 to -8.00D (-2.00D auxiliary lens)
Astigmatic Axis Scale: 0 to 180° in 5° steps
Cross Cylinder: ±0.25D, reversal type (synchronized with astigmatic axis)
Rotary Prism: 0 to 20 D in 1 D steps
P.D. Adjustment: 48-80mm; step 1
Forehead Rest Adjustment: 16mm
Convergence: The optical axes of the lenses are aligned at a distance of 400 mm from enabling convergence = 57mm to 80mm.
Corneal Distance: 2 mm forward and 5mm backward from a standard plane with scale?