According to historical record, the first use of magnification was in the 5th century BC by ancient Egyptian hieroglyphs. And corrective lenses were firstly used in the 9th century. Whether these records are true or not, it is undeniable that eyeglasses used for vision correction have been around for quite a few decades. In the long history of glasses, there have happened significant changes or improvements. Modernistic glasses differ greatly from those old ones in nearly all aspects. The biggest and most noticeable difference is the eyeglasses availability. Dating back to even one hundred years ago, it was uneasy to get a pair of prescription glasses. Only the elite had access to Rx eyeglasses, because of the scarcity. And at those early days, both lens and frame technologies were quite less advanced than today.
Optical lenses used in prescription glasses are the essential part which provides visual correction. After several centuries’ development or advancement, modernistic glasses are now greatly contributed by advanced lens technologies. A simple example is that superior lens materials like high index plastics allow strong lenses to be regularly thin. This was impossible in old glasses. And this improvement is quite meaningful because there is a large group of people who suffer from severe vision conditions. Another improvement in the Rx lens industry is the invention of multifocal lenses. Single-vision lenses as the traditional and regular form are not competent in some circumstances. Patients who have both presbyopia and myopia or hyperopia will discover that multifocal glasses like bifocals and trifocals much more helpful.
Lens improvements made by modern eyeglasses are certainly not limited to the two points mentioned before. Now it is still necessary to discuss some changes in frame style that can be seen in modernistic glasses. The most noticeable facet is frame color. Modern eyeglasses are now available in any possible colors, while traditional glasses appeared only in black or gray. In recent years, yellow frames, orange frames and some other models are quite fashionable among especially young ladies. This is unimaginable by our grandmothers and earlier generations.