What difference do mono-focal glasses and multi-focal glasses have?
A mono-focal lens is a lens with one focal point. Usually, the myopic far-sighted presbyopia that we see belongs to mono-focal glasses. There is only one diopter on one lens, and this is the single focal point. Multi-focal glasses are lenses that have multiple focal points, that is, multiple diopters. Both mono-focal glasses and multi-focal glasses are visual correction tools, but mono-focal glasses can meet basic vision needs, like fatigue relief, control of depth of diopters, and focus on different distances such as the need to see far and near.But because there are many different diopters on a multi-focal glasses lens, so the elderly can not only see far after wearing. When they see close distance, they do not need to take off glasses or wear reading glasses. Wearing multi-focal glasses is not easy to fatigue.
How to Choose Glasses for Long Face?
Thick frame glasses: the third glasses for long faces we want to mention are the thick frame glasses. They can add width to your face for a more balanced look.
Aviator glasses: to balance the feature of long face, aviator glasses are a good choice, which includes a wider top and more narrow bottom, pairs perfectly with a long face.
Long faces have a long list of options when it comes to selecting the perfect pair of frames. Whether you are looking for a more polished, academic look or prefer a more casually cool style, you can find a pair of glasses making your personality pop.
Therefore, if you need a pair of glasses for long faces, you can try Koalaeye glasses. They are stylish and cheap. In addition, you can get a pair of prescription glasses online and the glasses will be mailed to you.
What Glasses Lens Thickness Should I Choose?
In this section, we will show you how to choose glasses lens thickness. Lens thickness will depend on the strength of your prescription, your pupillary distance, the size of the frame and the lens material. Usually, high prescription glasses are thick.
If you have moderate nearsightedness, you should choose thinner lenses at the edge thickness of your lenses will be more visible. If your sphere prescription is between -2.50 and -4.00, the lenses with a refractive index of 1.6 would be an ideal choice. A lens with a refractive index of 1.67 is suitable for sphere prescription between -4.00 and -6.00, and any prescription over that a lens with a refractive index of 1.74 will be more suitable.
So, when you purchase prescription glasses, consider the glasses’ lens thickness also. If you want to get a pair of prescription glasses online, Koalaeye Optical is recommended. It is an online optical store and provides all kinds of eyeglasses, sunglasses and frames. Besides, these glasses are stylish and cheap. If you purchased, the glasses will be mailed to you with great convenience.
Use your two hands to wear and take off the glasses.
When you pick and wear glasses, you need to grab the temples with both hands and take them off. When you pick and wear glasses with one hand, it is easy to cause deformation and loosening of the glasses. According to the convention of international glasses design and manufacture, you should fold the left temple first. When placing glasses, keep the convex side of the lens up to avoid scratches on the lenses.
Seek professional help.
Many plates, TR glasses have fixed nose pads that cannot be changed. But the metal material of the nose pad can be changed. An optometrist who is a professional optometrist may not be a good adjuster. There is no conflict between the two. The skills about that shall be developed in a lot of practice. For a seemingly easy operation, its strength is invisible real skills.
Progressive lenses and single vision lenses
Single vision lenses are the most widely used optical lenses and are suitable for the general population.
Progressive lenses are suitable for below people.
① Myopia control lenses for teenagers. Progressive lenses are used to relieve visual fatigue and control the development speed of myopia.
② Anti-fatigue lenses for adults. Progressive lenses are used for teachers, doctors, people who use too much computer at close range to reduce visual fatigue caused by work.
③ Progressive lenses for Middle-aged and elderly people. A pair of glasses for middle-aged and elderly people to easily see near and far.
About the early domestic anti-reflection coating lens
Chinese coated lenses appeared in the mid-1980s. At that time, Europe (such as France and Germany) and Asia (such as Japan, Singapore, and Taiwan) had already launched coated lenses to the market, and the grade of lenses was evaluated based on the quality of the anti-reflection effect. Among them, Germany and France were the two leading countries in technology. Technically, the use of French original film material (referred to as H2) can reduce the effect by 99.98% (refers to the light transmittance, the same below). Almost you can not see the reflection, but the material is expensive. Therefore, the coating lens which is currently used in the world is born. The anti-reflection effect is controlled at about 98%, so the coating cost is greatly reduced. And it is accepted by consumers because it presents various colors, especially green. At the same time, because at the same time, it can be easily distinguished from non-coated lenses. It can reflect the high-grade film lens, and it is accepted by the sales staff.