Problems of visual optics

Istockphoto©Bliznetsov

99% of the population suffers from presbyopia, which is a loss of focusing ability with age (after the age of 40). Visual disorders such as myopic eye, hyperopic eye or lens astigmatism are associated with some kind of genetic defects or acquired vision defects, which concerned with the failure to eye lens accomodation. Generally, these types of impairments is induced by overwork or overstrain of eye’s muscles, the ocular muscles, in time of school attending, reading, working on a computer, and so on.

Most of the population suffering from eyes disorders wears spectacles or contact lenses in order to correct the disorder. A combination of disorders may complicate the use of spectacles since certain lens has to be used for far-vision and another one for near-vision while contact lenses fail to correct the disorder. Today for precise vision on various distances bifocal, trifocal or even multifocal are available (see Fig. 1, 2). Latest development in the designing of multifocal lenses allows expecting for reception of lens surface topography optimized for correction of eyesight of concrete consumer

 

All these solutions are not sufficient for most people that need to shift quickly the visual attention from near to far objects. Moreover, bifocal, trifocal and even multifocal (progressive) eyeglasses have dead-zones and limited field of vision for close and middle distances. Wearers of glasses with progressive lens must also tilt a head at between 35- and 45-degree angles for clear close-up vision, but their view to either side of the reading zone is distorted. So, most of eyeglasses consumers still have a feeling of permanent discomfort.