Semitransparent membranes of various degrees of opacification which can be pressed onto a spectacle lens to reduce visual acuity. There are 10 degrees, graded from 1.0 (6/6 or 20/20) to complete occlusion. They are used in the treatment of amblyopia and intractable diplopia. Syn. Bangerter graded occluder; Bangerter occluder. See occlusion treatment; penalization.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann