China has become the world’s highest incidence of myopia country. According to the statistics, the number of people whose eyesight is bad has reached more than 300 million which is about the one-third of the world’s number.

When you want to match a pair of eyewear suitable for yourself, to get one appropriate is the most important thing. As to those who need to wear eyeglasses, the frame is the most essential. When the consumers are selecting the eyeglasses, they should not only consider the distance between the eyeglasses and the face, the nose and the pupils, but also take the color of skin and the color of hair into consideration. Only through this way, you can show your temperament and demeanor.

Generally speaking, the people whose faces are wide are not suitable to the small eyeglass frames. And the people with long and thin faces should not take the large frames. As to the children, the best choice is the plastic frame. For some consumers who are high myopia and high hyperopic, because the refraction is too high, they’d better choose the small frames. And the lenses are better if are smaller. There are some common kinds of frames as follows: the plastic frame, the metal frame and the nylon frame.

However, the types of lenses are fewer compared to the types of frames. But its quality is the determinant to measure whether the pair of glasses is good or not. So the consumers must be careful when choosing the lenses. The glass lenses are wear-resistant but relatively speaking, its weight is heavier than that of other lenses. And such lenses are easily broken. The polymer resin lenses have a lighter weight than that of other lenses. They are not wear-resistant and not easily broken. But the hardness of them is lower and it is easy to fluff and scratch on the surface.

To measure the quality of a pair of eyeglasses, besides the materials, you should also have a careful look at the refractive index of the lenses. The higher the refractive index is, the higher the price is.

In a word, the frame and the lenses are the most important parts of the glasses. When choosing a pair of eyeglasses, you should take them into consideration.

The materials of glasses frames are varied from past to present with the development of technology. Materials are of crucial importance since a large part of the glasses is made of one material. The quality of the material directly influences the quality of the glasses. Here, we want to introduce some kinds of the materials of glasses frame and you can choose the one you like according to your own situations.

First is stainless steel. Stainless steel is a kind of steel alloy that has an oxygenation protection on the surface. They will not easily get cauterization. So when in hot summer and you have sweat on your faces, you will not worry about cauterization. The capability of flexibility and mechanical is good for stainless steel. This kind of material can be made to like arc that might give you a sense of coziness. They can have many colors too. The disadvantage of stainless steel is hard to jointing for its intension.

Second is the alloy of aluminum and magnesium. Glasses made of the alloy of aluminum and magnesium is light in weight and cheap in price when compared to that made of titanium. The color and lustre of glasses made of the alloy of aluminum and magnesium is fresh and shining. This character of the glasses will reflect that you are as fresh as paint.

Third is eyeglasses made of titanium. Titanium is a kind of material that is often used recently. So they are called materials of valuable merits. If businessmen use this kind of material to make glasses, the glasses will be very light in weight. But the disadvantage is obvious too. They are too expensive for ordinary people.

Fourth is the famous memory plastic optical. Memory plastic optical has wonderful flexibility. And light in weight. Glasses made of this material will not be easily getting distortion. Though be distorted, they will soon return to its original shape. And people who wear glasses of this kind hard to be hypersusceptibility. Colors of memory plastic optical also varied according the colors of the lenses.

You may hear some of the above-mentioned materials. If you have decided to buy the prescription glasses, you can get some information about this for they can let you purchase glasses with good qualities. And if you care about the price, you can shop on the Internet since in this way, you can have glasses with much cheap price and you do not have to go out in this hot weather. The only thing you have to do is chick your mouse of computer and wait patiently for your new reading glasses.

With the development of technology, there are more and more glasses frame materials for eyeglasses, and today I will mainly introduce three common eyeglass frames materials which are aluminum, titanium glasses and steel.

Before you will really know what are aluminum frames, titanium frames and steel frames. You should know the concepts of stiffness, strength and weight first.

Imagine you clamp one end of a metal bar in a vise, and you hang a weight on the free end, causing the bar to flex temporarily. When you remove the weight, the bar snaps back to its original shape.

Different materials will flex different amounts for the same amount of force applied. This is stiffness also modulus.

Now imagine hanging a heavier weight on the bar, so heavy that it becomes permanently deformed. When you remove this weight, the bar does not snap back all the way to its original shape, but remains bent to some extent. When the metal changes shape permanently, it is said to “yield.”

Different materials can withstand different amounts of force before yielding. This property is strength.

In addition to the strength and stiffness, there’s also the question of how heavy a given volume of the material is. This is called weight also “specific gravity.”

Like stiffness, the specific gravity of a given metal is not significantly affected by the addition of different alloying elements, which means that all steel is equally heavy.

Then you should know some facts. The modulus of aluminum, steel and titanium are 10-11, 30 and 15-6.5. The yield points of them are 11-59(4-22 annealed), 46-162 and 40-120. The specific gravity of them is 168.5, 490 and 280.

The identical steel and titanium frames will be about equal in strength. However, the titanium frame will be about half the weight and half stiffness. So such a titanium frame would likely have a whippy feel due to the reduced stiffness. To compensate, builders of titanium frames use somewhat larger diameter tubes to bring the stiffness more into line with what riders like. This tends to increase the weight a bit, but by making the walls of the larger tubes a bit thinner, they can compensate to some extent, and come up with a frame that is still lighter than a normal steel frame.

The situation with aluminum is even more pronounced. The “identical” aluminum frame would be 1/3 as stiff as steel, roughly half as strong, and 1/3 the weight. Such a frame would be quite unsatisfactory. That’s why aluminum frames generally have noticeably larger tubing diameters and thicker-walled tubing. This generally results with frames of quite adequate stiffness, still lighter than comparable steel ones.

Therefore, anyone who tells you that a particular brand of steel (or aluminum, or titanium) is “lighter” or “stiffer” than another brand or model is blowing smoke. You should choose your frames according to your own condition. If you are unable to handle this thing, you can go to some online glass stores, such as www.visionsking.com, for advice.In VK,you can buy reading glasses,prescription glasses and cheap glasses!