Sunglasses For Fishing - Prosun
The headquarter of Prosun?is located in Xiamen City, Fujian Province. ?In the development process of more than 20 years, Prosun?has been committed to the research and development of optical products. The product design style has closely followed the trend, and the quality materials have useful workmanship. And the comfort is continuously improved, with the combination of fashion design concept and science. It is committed to providing young people's favorite glasses products.
Benefits of Progressive Lenses
Progressive lenses are different from traditional reading glasses and bifocal glasses in that bifocal reading glasses have to constantly change the focal length, causing fatigue. And there is no clear dividing line between the two focal lengths. They are more comfortable, more beautiful. When you see far or see near, a pair of glasses can be done, so they become the best choice for old people little by little.
Progressive lenses allow multiple fields of view to be merged into a single lens with no discernible difference between the fields themselves. Degrees of the lens vary gradually from far to medium to your full reading. This is why progressive lenses are often regarded as no-line bifocals or trifocal points.
The refractive index of lens
Refraction law is discovered by Dutch mathematician Snell.It is the law that determines the direction of refracted light in the phenomenon of light refraction. When the light from the first medium (refractive index N1) into the second medium (refractive index N2), part of the light from the first medium into the second medium at the smooth interface will be refracted. The index of refraction is the ratio of the speed at which light travels in a vacuum to the speed at which light travels in the medium. For glasses lenses, the higher the refractive index, the thinner the lens, that is, the lens with the same center thickness and the same degree, the lens with the higher refractive index has thinner edges than the lens with the lower refractive index of the same material.
Acetate cellulose pellets are extruded by an injection molding machine, which is called an injection frame. Its characteristic is that it saves raw materials, can be mass-produced, has a lower cost, and is cheaper than a plate rack. But the firmness is not as good as the plate frame. However, injection frames are mostly used for glasses for the elderly and children because of their lightweight and resistance to allergies. The injection frame is made of laminated plastic. It is made by pasting a thin layer of plastic of one color on another thicker layer of plastic. Thick materials are mostly transparent pigments. It is also made of three or more layers of plastic.
What Are Bifocal Glasses?
Vision changes seem to be related to age. Presbyopia occurs in the middle age of one person, affecting your eye’s ability to focus. But it can be caused by bifocal glasses.
Bifocal glasses are divided into two parts to accommodate two different prescriptions in one lens. One area of the lens will have one prescription (usually distance) and a segment in the lower half will have the other (usually near vision).
Bifocal glasses were invented by Benjamin Franklin, who solved his own vision problem by taking the lens from his reading glasses and distance glasses and cutting them in half. Then remade the cut lenses into a single pair of bifocals and put the distance lens on top and the reading lens on the bottom.
However, the bifocal glasses come with some problems. So, in the following section, we will show you some common bifocal glasses problems.
Silhouette Rimless Glasses
They provide a range of options for rimless, full-frame, and half-frame styles. Their optics lab allows personal prescription lenses to be mounted on any frame and sunglasses. Here, fashion and function come together in an ultra-light titanium eyewear frame, using exclusive hingeless polycarbonate lenses. Minimal weight, hingeless construction, and form combine timeless framing styles with different kinds of lens shapes and breakthrough technologies.
Are progressive lenses good for driving?
Progressive lenses can help you see close, far, and anywhere in between. That means progressive lenses are good for driving. So you don't have to change your glasses on the way. With progressive lenses, you can easily see all distances. Standard lenses are more affordable than premium lenses, but premium lenses offer a wider field of view and are ideal for drivers.