Why should the surface of the lens be hardened?
Compared with glass lens, resin lens has the characteristics of lightness, safety, and comfort, but resin lens friction with dust or gravel in the process of use, resulting in lens wear and forming scratches. These scratches in the center of the lens can interfere with vision.
Therefore, in order to improve the wear resistance of resin lenses, it is necessary to add a layer of anti-wear film to the surface of the lenses. This is the hard coating technology of the lenses, which is called Hard coating.
What are the benefits of recycling old glasses?
Recycling old glasses contributes to sustainability and reduces waste. It is a way to give charity in addition to giving money. It can be able to teach children the importance and impact of philanthropy.
The inadequacies of bifocals
The field of vision is smaller than that of the single vision lens, especially for the close view. For example, reading and reading newspapers need to make it coordinated with the head movement, there are optical defects of image jump and image displacement. There is a boundary, and it is easy to be seen that wearing a bifocal lens exposes age. Bifocals clearly demarcate the near and far regions, affecting appearance and vision. And when far view and close view change, the objects will jump. Because most myopic patients have a lag in the adjustment response, wearing bifocal lenses not only does not delay the development of myopia but has side effects. Therefore, bifocals are not suitable for teenagers to control myopia, and only a few special patients need to wear bifocals.
What Are Progressive Lenses?
Progressive lenses have grown in popularity and are one of the most common solutions to treat vision loss that occurs with age or presbyopia. This eye condition occurs when the eye loses some of its flexibility and ability to adjust to clear seeing objects at different distances. Presbyopia often occurs among adults who are over age 40 and is very easy to correct with a proper and prompt diagnosis.
Progressive lenses are often used to correct this eye condition. Progressive lenses are a modern alternative to bifocal glasses, which provides two prescriptions in a single set of glasses. Bifocal glasses are a better solution than carrying around multiple pairs of glasses. Progressive lenses were developed to resolve some of those common issues and to provide better aesthetics. Progressive lenses provide a smooth transition and can accommodate up to three prescriptions and are a replacement for both bifocals and trifocals.
About Prism Glasses
The refractive index of the same medium is different for different colors of light. Different colors of light travel at different speeds in the same medium. Because the same medium has a different refractive index for various monochromatic light, and the deflection angle of each monochromatic light is different when passing through a prism. Therefore, white light through a prism will separate the monochromatic light, known as dispersion. What is the prism effect of glasses? As long as there is a deviation between the visual channel of the eye and the optical center of the lens, it can produce a prism effect. Therefore, the severity of the prism effect can be used to measure whether the glasses with the correct prescription are processed correctly and reshaped correctly.
Titanium is currently too expensive to refine.
It is highly demanding in buckling, stamping, cutting, and welding. The extraction of titanium, like that of aluminum before the 19th century, was quite costly and produced in limited quantities, so it was used only in extremely important fields, such as aerospace, electronics, precision instrument manufacturing, and so on.
How to test a blue-light lens?
Blue light-blocking glasses have many membrane layers, and all kinds of colors of the film are not the same. Actually, the membrane layer of anti-radiation effects is not large but has high strength and chemical resistance of lining norm of glasses and the effect of protection for the eyes is very important.