The birth of progressive lenses
In 1907, British optometrist Owen Aves first proposed the concept of progressive lenses and got the first patent of progressive lenses. In 1910, Henry Orford Gowlland designed and made a similar lens in Canada, but technical limitations prevented it from succeeding. In 1959, Bernard Maitenaz, a French optical and mechanical engineer, developed the first progressive lens, which was successfully put into the commercial market for the first time and became a milestone in the history of world optometry. With the development of science and technology, the design of progressive lenses has been greatly developed.
How to buy prescription glasses online
Consumers should choose different styles of frames according to their age and professional characteristics. Because everyone has different face shapes, different interpupillary distances, and different diopters, the size of the frames should vary from person to person.
Lenses are divided into glass lens, resin lens, and PC lens, and you can choose according to your preferences. The glass lens has a stable refractive index, good abrasion resistance, and stable optical performance, but it is relatively heavy and easy to break. Resin lens with high light transmittance is light, safe, and not easy to break, but the surface is easy to wear. PC lens has a high refractive index, but the surface is easy to wear.
How do bifocal reading glasses work?
Bifocal reading glasses have two different lenses on the same lens. The top of the lens is your normal distance prescription, while the bottom is for close-up viewings, like reading. The two lenses allow you to alternate between them by moving your eyes up and down as needed. A bifocal lens is a type of lens that has two different areas of vision: one for close range and one for long-range. Typically, the upper section covers remote vision and the lower section covers reading. With a traditional bifocal lens, you can see the difference between the two lenses because the lower curve is a little different.
How do drivers wear glasses or sunglasses better?
We should pay attention to the dim light at night on the impact of vision, At night, for the people who wear glasses, it is best not to drive, but to prevent fatigued driving. If you need to drive, you must choose clear and appropriate optical glasses. When the light is strong in the field, it is advocated to wear light-colored sunglasses with appropriate degrees to ensure driving safety. When wearing glasses to drive, for the observation of road conditions, we should focus on the use of the head movement. Do not use eyes to move, to prevent the effect of the prism, especially the patient with high myopia should pay special attention. Shaded sunglasses, coated with reflective material, block out light from above and increase horizontal and lower light, which makes it easier to see the platform. Clip-on sunglasses are suitable for people who wear glasses themselves. You can go straight with a pair of myopic sunglasses for a higher price.
Pure titanium has special current characteristics
Pure titanium can guide electron fluctuations to produce ions, causing the current to tend to ionize. The positive and negative ions can adjust the adverse effects of electromagnetic waves caused by the body's biological current disorder and have a great health care effect on the human body in order to avoid fatigue, muscle stiffness, soreness, and other symptoms or problems.
What Are Varifocal Glasses?
Varifocal glasses, also known as varifocals, varifocal lens, PLA, or progressive lenses, have a gradual change in strength from the top of the lens to the bottom with multiple focal points in between. Unlike bifocals, varifocal glasses have no specific area of lens strength, but progressive lens zones.
The way to look through varifocal glasses depends on what you want to look at. If you are looking at the distance, you look through the top of the lens. If you want to look at the close objects, you may need to move your eyes lower to keep the objects in focus. For the best close-up focus, you need to look through the bottom of the lens.
The benefits of varifocal glasses are that they do not need to buy or prepare 2 separate pairs of glasses or need to switch between frames for different vision needs.
However, if you wear the varifocal glasses for the first time, you may come across some problems.
About Glasses Donation
Some enterprises adhere to the quality of survival. They always adhere to the credibility and development of the business philosophy, investing in public welfare undertakings and fulfill their social responsibilities. They donate glasses, have free vision tests, and put forward reasonable love eye care advice according to the results of the test to the public.