The industry of eyeglasses eyewear has been largely expanded and currently there are single-vision glasses and multifocal glasses for different groups of people. The average life span among individuals in developed and thriving countries stays on the rise. There is a big group who are still working after 50 or even 60 years old. It is quite understandable that some people want to work as long as possible. However, some of the elderly folks may find that their vision condition is a big obstacle even if they have still enough body energy. Like young people who rely on myopia glasses or hyperopia glasses during work or entertainment, the senior group possibly has to resort to Rx eyeglasses for help. For this special group, regular single-vision glasses are no longer competent due to the existence of presbyopia. Caused by the eye’s natural aging, this condition will affect almost all elderly people.
Multifocal glasses like bifocals, trifocals and progressives are the suitable items for the senior. These devices help deal with two or three vision problems that are equally bothersome. But for those who still work on a regular basis, normal types of multifocal glasses are not helpful enough. Eyewear designers have in turn developed occupational eyeglasses eyewear for specific jobs. These are actually variations of bifocals or trifocals. In the following part, we introduce some of these examples.
An auto mechanic suffering from presbyopia may find a pair of bifocal glasses with Double-D lenses especially helpful. As widely known, such a worker needs to look down to read and look overhead to view the undercarriage of a car on a lift. As a result, it is necessary to gain clear up-close vision in both of the directions. Double-D bifocal lenses are thus the perfect solution. Librarians and mail clerks are also good candidates to this form of occupational eyewear.
Another form of occupational eyeglasses eyewear uses E-D lenses. Such a lens has a distance correction in the top half and an intermediate correction in the bottom half. There is still a D-shaped segment offering near correction in the lower half of the lens. This lens design provides a wide field for intermediate vision and also enables wearers to see close-up and in the distance. Television production people are target users of these glasses.