Glasses are frequently replaced.
In the United States today, there are more glasses than people. Counting prescription glasses, sunglasses, and over-the-counter readers, there are now more than 400 million pairs on the market. According to the Vision Council, an industry group, they swap out a brand new pair of glasses every two years on average.
The Price of Progressive Lens
On both sides of the lens of the progressive lens, some places are deformed, which makes the image blurred. In addition, it has a narrow field of view in the near and middle distances. The narrow focus point for a long time can easily make the eyes tired. It is suitable for the alternate vision of far, middle, and near. Under normal circumstances, the price of the progressive lens is different from the purchase merchant, region, brand, and quality, but the price of the progressive lens on the official website is between 30-85 US dollars. Of course, some products will be less than $30, or more than $85.
How much do plano lenses cost?
If at big shop downtown, the price of the lens will exceed a hundred, but if you walk the campus store, will be a lot cheaper. Generally is 30-40 at least(not the poor quality, but the price is reasonable for students).UV protection, anti-fatigue, prevention of radiation, computer and television are the basic functions. In the campus store, it is several hundred or so, which can be matched with relatively good quality. Generally, the price of radiation-resistant resin lenses and frames is about 150. If you want to choose a better one, The price can be very high.
Wearing glasses correctly will not get deeper degrees
The development of myopia is not directly related to wearing glasses. Patients with myopia wear suitable glasses and pay attention to eye hygiene, and the degree of myopia will stabilize at a certain level. But if you think that with glasses, everything will be fine. If you don't pay attention to eye hygiene in normal times, if you continue to keep your eyes in a state of fatigue for a long time, it will lead to vision loss and deepening of myopia. In addition, wearing improper glasses such as no optometry or inaccurate optometry, too large power, will increase the burden on the eyes, reduce vision and deepen the power. For some people with high myopia (more than 600 degrees), although they insist on wearing glasses, the degree will still deepen, accompanied by changes in the fundus, which is medically called pathological myopia. This deepening of myopia is related to the degree of myopia and family and has nothing to do with wearing glasses.
How to buy anti-blue light products?
In order to further standardize anti-blue light products and make all kinds of products effectively protect eye health, relevant standards have been formulated. Based on the different effects of blue light in different bands on the human body, the transmittance of blue light in each band is required in the standards.
For example, in the band range of 415-445 nm, the transmission ratio of light is less than or equal to 80%, and more than 445 nm, it is greater than 80%.
Types of aspheric lenses
There are two types of aspheric lenses: single aspheric surface (single aspheric surface for short, different from the outer aspheric surface and inner aspheric surface) and double aspheric surface (double aspheric surface for short). For the outer aspheric surface, convex is an aspheric surface and concave is a spherical surface. For the inner aspheric surface, a convex surface is a sphere, and a concave surface is an aspheric surface. In addition to correcting aberrations, the double aspheric lens also improves the effective field of vision compared to the single aspheric surface. When people's eyes look through the edge of the lens to see things, like driving when looking at the reflective mirror, it often affects vision because of the large aberration at the edge of the lens. Previous designs of aspheric plates have analyzed a single ray of light passing through the center of the pupil. Wavefront technology controls the entire beam of light passing through the pupil, eliminating high-order aberrations.
Glasse for square faces
It's a square face. People with square faces have wider cheeks and a shorter face that looks firm and has a softer facial line. So select a square or a polygon-shaped frame. Usually, square faces visually shorten the face. And they can give a person a kind of relatively strong feeling, like a boy's face. So choose something slightly wider than your face shape, so that they can have the modified effect.
