In the modern society, there are so many people who need to wear prescription eyeglasses or contact lenses. Another point is that many jobs or sports require the use of safety eyeglasses. This can be testified by the cases of eye injuries occurring every day worldwide. As the public enjoys a longer life span, many people in their 40s and 50s still remain in their jobs. However, the traditional problem called presbyopia is sometimes unavoidable. In this sense, this group of people needs both presbyopia correction and eye protection when they are involved in a dangerous activity. Bifocal and progressive bifocal safety glasses are the perfect solution for these people with special needs. Traditional bifocal safety glasses and progressive ones can both meet these two requirements, even though they are slightly different in lens design.
Progressive safety eyeglasses can offer smooth power transition for patients who need vision correction at various distances. Using bifocal safety glasses, it is no longer necessary to remove or reposition the glasses in order to focus on distant objects. Progressive bifocal safety glasses enable the wearers to perceive things in the distance by seeing through the upper section. And objects that are close up can be viewed by utilizing the lower part of the lenses. Nowadays, most manufacturers of these glasses only produce lenses with diopters ratings of plus 1 to plus 2.5. And lenses outside of this range will be extremely expensive and will be provided on a customized basis.
Since progressive bifocal safety glasses are supposed to offer multiple functions and are relatively expensive, they are necessary especially for some groups of people. The first group is presbyopic patients with jobs involving the operation of heavy equipment or materials that are hazardous to the eyes. These people need their eyes well protected from objects in the workplace. The second group is presbyopic people enjoying hunting or shooting. They need to read a map frequently in some cases.
C: Progressive bifocal safety glasses are needed especially by some groups of people. Presbyopic patients with a job involving heavy equipment or hazardous materials and those enjoying hunting or shooting are potential targets.