Posts Tagged ‘progressive’

Why Should You Choose Progressive Lenses Over Bifocals And Trifocals

November 28th, 2011

The discussion and debates surrounding the topic of whether progressive lenses should be chosen over their bifocal and trifocal counterparts have been going on since like forever ago. While the two groups of people following them separately have perfect enough arguments and reasonings, it seems that the ones who favor progressive lenses are gradually taking the upper hand. Let’s herewith hear their arguments and decide for ourselves whether they make sense.

First of all, these eloquent fine debaters would say, lenses of progressive glasses provide better visions than bifocals and trifocals do. This is a statement with much truth in, basically in three aspects. First, progressive lenses provide more precise powers. Bifocals and trifocals, as already revealed by their names, only have two or three different powers blended onto the same lenses, which means one can only get clear vision for two or three ranges. For most people this might come as a huge harassment since real life experience tells us that only two or three powers don’t even come near as enough for our daily uses. Progressive lenses, on the other hand, provide a gradual progression of prescription powers, with which almost any vision need could be met. Secondly and probably the most importantly, progressive lenses spare their wearers off the nettling experience of image jump, in which sudden changes of powers across the separating lines could cause distortion to the image and nausea and other reaction to the wearer. Progressive lenses, with the ingenious design of gradual progression of powers, offer wearers a natural smooth view that resemble one that you get with your natural eyes. Precise powers and natural view, it can’t be to much of a mistake to say that progressive lenses are the ones with better vision.

Another argument that keeps coming on the lips of those progressive lenses advocates has to do with aesthetics. As is known to all, bifocal and trifocal lenses have these annoying visible lines that give away the wearers’ age in no time. Most people have scruples with bifocals due to this defect. With progressive lenses, they don’t have to worry. Rid of the nettling lines, progressive lenses immediate create a youthful and energetic vibe to the faces of the wearer.

Types of prescription glasses

February 17th, 2010

Most of the corrective eyeglasses should be checked and prescribed by eye doctors, which are called prescription glasses. There are 4 types of prescription glasses which are designed and made to correct vision based on different circumstances.

The mostly used prescription glasses are for single vision. Most of eyeglasses wearers fit in this category. Single myopia, hyperopia and astigmatism only needs single correction. This group of prescription glasses is the easiest portion with the least return and complaints.

The second type is called double focal of bifocal prescription glasses. Bifocals were invented by Benjamin Franklin. He fused the farsighted lenses with the nearsighted one, thus he freed himself from interchanging two prescription glasses frequently. This type of prescription glasses are used by patients of presbyopia who are generally over 40s and are synchronously near- and far-sighted. Bifocal prescription glasses have two pairs of optical centers, which are equal to two pairs of eyeglasses.

Trifocal prescription glasses mean there are three pairs of optical centers. Its basic function is similar to bifocal prescription glasses except that trifocal possesses the center focal point which is for intermediate vision for a smoother transit from near to far.

The fourth is called progressive prescription glasses. This is also called no-line bifocals, for use by presbyopia patients to have a better look, as bifocal prescription glasses give other people a sign of being “old”!