Progressive lens | 合法醫療器材資訊網

Progressivelenses,alsocalledmultifocallenses,progressiveadditionlenses(​PAL),varifocallenses,progressivepowerlenses,graduatedprescriptionlenses,​ ...

Corrective lens used in eyeglasses

Progressive lenses are corrective lenses used in eyeglasses to correct presbyopia and other disorders of accommodation. They are characterised by a gradient of increasing lens power, added to the wearers correction for the other refractive errors. The gradient starts at the wearers distance prescription at the top of the lens and reaches a maximum addition power, or the full reading addition, at the bottom of the lens. The length of the progressive power gradient on the lens surface depends on the design of the lens, 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. They are also known as multifocal lenses, progressive addition lenses (PAL), varifo...