What Are Polycarbonate Lenses?
Polycarbonate lenses are made from a type of plastic that is famous for its durability. Polycarbonate lenses are perfect for those who are doing sports while wearing glasses. It is also used in children’s glasses since kids are much less careful with their glasses than adults.
What Are Progressive Lenses?
Your eyes change with your age. When your reach your 40s, you may find that it is difficult for you to focus between a book, a website on a computer screen and the conference room whiteboard. Progressive lenses are growing in popularity among people who need help seeing near, far and in-between.
Progressive lenses have grown in popularity and are one of the most common solutions to treat vision loss that occurs with age or presbyopia. Progressive lenses have a seamless increase in magnification from the top to the bottom of the lens, helping you see clearly at all distances with just one pair of glasses. The top portion of the lens enables you to see the far-away objects, the middle portion of the lens enables you to focus on the intermediate objects and the bottom to see objects close-up. The prescription changes little by little across the lens surface providing a gentle transition.
After knowing what the progressive lenses are, do you know what are the pros and cons of progressive lenses? If not, keep on your reading and we will show you some information.
TR90 glasses frame
TR90 is not easy to deform and break, and it can withstand high temperatures and strong impacts. In addition, its material is relatively light, so many young people also like such glasses frames.
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.
What is a progressive lens?
A progressive lens is a lens whose upper sides are used to see far, and the lower side is used to see near. The distance from the fixed distance power above the lens to the near power fixed below the lens does not change suddenly, but a gradual transition between the two through the gradual change in refractive power.
Standard progressive lenses are multifocal lenses with three observation areas, farsightedness, intermediate vision, and nearsightedness. Unlike bifocals, there are no visible lines between each viewing area. They have a seamless, invisible design, where the optical power changes 'gradually' throughout the lens. Many people confuse 'bifocal' or 'trifocal' with 'progressive' but remember that bifocals and trifocals have visible lines in the lens, while progressive lenses do not. Because progressive lenses have no lines in the lens, they are more popular multifocal lenses than bifocal lenses. However, is progressive lens good for eyes?
Why do my glasses hurt the top of my ears?
The problem caused by the angle of the glasses rubbing the ears is mainly caused by the following several conditions. Firstly, it may be that the outer angle is not enough so that the feet of the glasses press the ears too tightly. Secondly, the two sides of the glasses are of different heights. Thirdly, the last situation may be caused by a problem within the angle of depression.
The categories of rimless glasses
Rimless glasses can be divided into metal rimless glasses and plastic rimless glasses according to the material. According to the metal category, they can be divided into nickel-copper alloy, memory titanium alloy rimless frames.
According to the elastic order of the frame, the softest and elastic kind is the plastic rimless glasses. The benefits are the lightest weight and the lowest price. The disadvantages are the short service life, faded look after the sun, and single appearance, which are suitable for children or teenagers in the stage of corrective treatment. The second elasticity is the memory titanium alloy rimless frame. They use aviation metal titanium as the raw material, suitable for people with sensitive skin, and have lighter quality, better durability, more styles.
