Aspherical Lens 20D

Specifications,
Magnification ratio: 2.97X
Static FOV: 50°
Working distance: 47mm
Clear aperture: Ø47mm
Dimension:  Ø56 X20mm

Usage Guider:
1.The silver ring on the lens holder should be held toward the patient's eye during examination, which can ensure the right using direction and may provide for best image quality;
2.Keep the lens centring on the patients pupil;
3. Hold the lens far enough from the patient's eye so that the retinal image has the same diameter with the lens;
4.Keep the illumination sources as dark as possible to minimize reflections and image contrast;
5.Keep the lens clean to minimize glare from the lens surface.