Hence, they are not able to focus in a manner similar to the youthful lens.This process can occur in as little as 350 milliseconds. By the fifth decade of life the accommodative amplitude can decline so that the near point of the eye is more remote than the reading distance. Once presbyopia occurs, those who are emmetropic (do not require optical correction for distance vision) will need an optical aid for near vision; those who are myopic (nearsighted and require an optical correction for distance vision), will find that they see better at near without their distance correction; and those who are hyperopic (farsighted) will find that they may need a correction for both distance and near vision.Note that these effects are most noticeable when the pupil is large; i.e. The age-related decline in accommodation occurs almost universally to less than 2 dioptres by the time a person reaches 45 to 50 years, by which time most of the population will have noticed a decrease in their ability to focus on close objects and hence require glasses for reading or bifocal lenses.In addition, the lens has the capability for adjustment during or after implantation to provide high-acuity vision throughout life.
Accomodating lenses comments