Descriptors | Spectacles (eyeglasses), Ophthalmic equipment, Ophthalmology, Medical prescriptions, Spectacle lenses, Thickness, Tinted glass, Tolerances (measurement), Spectacle frames, Mass, Marking, Visual inspection (testing), Shear testing, Grades (quality), Classification systems, Durability, Impact testing, Refractive index, Transparency, Transmittance, Optical dispersive power, Absorption (waves), Ultraviolet radiation, Reflectance factor, Testing conditions, Test equipment |