E-commerce is a major factor in the U.S. economy because it assists companies with many levels of current business transactions, as well as creating new online business opportunities that are global in nature.
Eye Health. A bifocal is a lens that has two focal points, usually one lens for viewing distant objects, and one lens for viewing close objects. A bifocal is also known as a multi-focal lens. Ben Franklin is credited as the inventor of the original bifocal lens. Presbyopia.
There are many different types of bifocal and multifocal lenses available on the market that correct different types of vision disorders. Multifocal and bifocal contact lenses are very similar to their glasses counterparts. They are available in rigid gas permeable, soft forms, and in a hybrid form.