What Are Trifocal Glasses?
Trifocal glasses and no-line progressive lenses are multi-focal glasses, meaning that their lenses offer multiple correction fields. Whether you have been wearing multi-focal glasses for a while, or you have just begun to look at options for correcting vision after 40 years old, you may have heard the terms trifocal or progressive glasses.
Trifocal glasses have three different corrective lenses within one lens to offer you intermediate, distance, and near correction. Trifocal lenses look and perform similar to bifocal lenses, with an added viewing zone to help correct vision in the intermediate field, and two visible lines where the viewing zones change.
Have a try and confirm the front and side of the glasses.
Confirmation data: pupil height, flat frame surface, size of frame surface, the harmony of nose arc, the contact area of nose support, size of temple bend. Finally, remember a big principle: You should have no sense of pressure, and in a small range of motion, the frame does not shift. Good glasses should be perfectly integrated with the face so that people can not feel the existence of glasses. Good design is invisible. The lens above 800 degrees will be slightly heavy, so it is not recommended to choose the elastic temple and smooth metal temple. The temple is too slender, and at the same time is all metal, easy to slide frequently.
What Is Polycarbonate Lens?
Polycarbonate was invented in the 1970s for aerospace applications and is currently used for the helmet visors of astronauts and for space shuttle windshields.
Polycarbonate lenses were introduced in the early 1980s in response to a demand for lightweight, impact-resistance lenses. Since then, polycarbonate glasses have become standard for safety glasses, sports goggles, and children’s eyewear.
Polycarbonate glasses come with a lot of features such as thin and light and they provide 100% percent UV protection and are up to 10 times more impact-resistance than plastic pr glasses lenses.
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.
Types of Varifocal Lenses
Elite varifocal lens: it has the widest field of vision at all focal points and is tailor-made to your exact vision and customized to fit within your frames. With the least distortion around the edges, they are very easy to adapt to and will give you the clearest level of vision available.
Occupational varifocal lenses: the last varifocal lens we want to mention is the occupational varifocal lenses. They are specific to different lifestyles, hobbies or occupation vision needs. If you frequently perform tasks at a particular distance for a long period of time, then you have a broader, more comfortable zone of vision.
The disadvantages of progressive lenses
- The field of view in the near and middle distances is relatively narrow.
- The adaptation time is longer and patients with greater astigmatism are not suitable for wearing.
- The peripheral aberration is large, and there will be large astigmatism in the periphery.
Rimless Glasses
This kind of glasses does not have a frame to wrap the eyeglass ring, only the metal nose pad, and temples, and the lens is fixed after being punched, which is relatively lighter. This kind of glasses is lighter and more fashionable and is the first choice for ladies in the workplace.
