Human vision and IOLs
Human vision is created the way, that young healthy eye is optimized for far vision. And to see clearly an objects from 2m and closer to the eye up to 25cm eye using so called eye accommodation mechanism.
As we age, eye accommodation degrades naturally and we start to use glasses for near or intermediate tasks, around age of 40.
Modern IOL are not able to fully restore it, however we do have advanced IOLs, which provide pseudoaccomodation to give patients freedom of glasses
What is visual distances in ophthalmology
Intraocular lenses types
Basic monofocal lens
Basic monofocal lens is a lens which have only one, fixed distance, where visual acuity will be maximised to see small details. Normally it is used for good far vision, while other vision distances will be seeing blurry, and you will need glasses to get sharp near vision, but at the time you use near glasses your far vision will be blurred.
Advanced monofocal lens
Advanced monofocal lens is a new class of lenses, which provides more visual acuity at intermediate distance at about 60-120cm from your eyes, while near vision is still blurry and you need reading glasses as well as with basic monofocal lens, and same way your far vision will be blurry while you use near vision glasses
Extended range of vision
Extended range of vision lens is an advanced optics lens, called EDOF, which gives great visual acuity at intermediate distance, and some lenses of this class may give you functional near vision without use of glasses. However near vision glasses are needed in many cases for demanding near tasks.
Full range of vision
Full range of vision lenes are intended to give a patient full spectacle independence for any distance, using different optical principles to create pseudoaccomodation. Normally patients with that lens do not need glasses at all, however in some rare cases glasses might be needed.
Proper IOL selection criteria
There is no way to restore your vision to full conditions of young healthy eye. However, proper IOL type and model selection may give you the best fit of technology features and your visual need.
Any IOL type has certain strength and visual compromises such as low visual acuity at particular distance, low vision quality in dim light conditions or sometimes unwanted visual effects around light sources during night time.
You implant an intraocular lens only once in a lifetime, so it is important to select the best fit options for your individual visual needs to get the best quality of life possible. To help you with that complicated choice, I have developed an automated tool you may use at this web site.