... The Otoscope is used to view the tympanic membrane and external ear canal to diagnose outer and middle ear pathologies. It ... small pupil.4. 19 lenses from 0D to ±20D: 0D, ±1D, ±2D, ±3D, ±4D, ±6D, ±8D, ±10D, ±15D, ±20D.5. Aperture wheel ... : Light spot be apart from reflector 150mm: =85 lxDiopter: 0D, ±1D, ±2D, ±3D, ±4D, ±6D, ±8D, ±10D, ±15D, ±20DAperture: red-free filter ...