View through a<unk>  at some distance. In normal use, a much smaller section of the<unk>  is used, so that the distortion is much smaller.<unk> es, also called multifocal<unk> es,<unk>  addition<unk> es (PAL), varifocal<unk> es,<unk>  power<unk> es, graduated prescription<unk> es, or<unk>  spectacle<unk> es are corrective<unk> es used in eyeglasses to correct presbyopia and other disorders of accommodation. They are characterised by a gradient of increasing<unk>  power, added to the wearer's correction for the other refractive errors. The gradient starts at the wearer's distance prescription at the top of the<unk>  and reaches a maximum addition power, or the full reading addition, at the bottom of the<unk> . The length of the<unk>  power gradient on the<unk>  surface depends on the design of the<unk> , with a final addition power between 0.75 and 3.50 dioptres. The addition value prescribed depends on the level of presbyopia of the patient. In general the older the patient, the higher the addition.
Progressive lens
Vitreous bulge
Fundic gland polyp
Fundic gland polyposis
Childhood cataract
Congenital cataract
Intrastromal corneal ring segment
Protruding ear