What are progressive lenses?
Progressive lenses, also called progressive multifocal lenses, are lenses that have multiple focal points. If it is divided from the focal point, the lenses can be divided into single focal lenses, bifocal lenses, and multifocal lenses. The original intention of progressive multifocal lenses is to provide natural, convenient, and comfortable correction methods for presbyopia patients. A pair of glasses can see far away, close up, and mid-range objects. After wearing them, one pair of glasses is equivalent to using multiple glasses. Because of the different nature, characteristics and applicability, progressive lenses are more expensive than single vision lenses.
Why does shape memory alloy have memory ability?
It starts with its microstructure. When a metal is solid, its atoms are always arranged in a regular way, forming a lattice. Under different conditions, such as temperature, metal may have a different structure, in which case it is said to be in a different phase. The change from one phase to another is called a phase transition. The properties of a metal change during a phase transition. The temperature at which a metal transforms is called the transition temperature. The difference between a shape memory alloy and other metals is that the phase transformation process in a shape memory alloy is reversible under certain conditions.
Different Types of Eyeglass Frame Materials
Acetate: The most popular frame material is acetate, also called Zyl. Zyl is a very cost-effective and creative option for eyewear and is extremely lightweight. The acetate frame material is also colorful.
Nylon: This frame material is used in some cheap eyeglasses. Nylon is strong, lightweight and flexible, and it can become brittle with age. Nylon is also a premier material for sports and performance frames, and also easily molded into today’s popular wraparound style.
TR90 Nylon: TR90 Nylon is durable, flexible, and lightweight. Glasses made with TR90 are extremely comfortable since they have a flexible quality. Besides, the TR90 Nylon frame material can bend under pressure and contour your face comfortably. So, it would be resilient to damage.
Ultem: Ultem resin is a flame-retardant and high performance thermoplastic. It comes with various features, such as high strength-to-weight ratio, heat resistance and high impact strength. This frame material is also durable.
The nose pad is very important.
It could be that the nose pad is too hard. You can replace it with a non-marked soft nose pad. It is recommended to choose a thin and long or broad-leaved nose pad, moderate hardness, which can effectively disperse the force of the nose, with stable support, bringing comfortable wearing. It avoids a soft nose pad on the bridge of the nose because of sweating or a long time to wear left indentation. Eyeglass frame nose pads are in direct contact with the bridge of the nose, and too hard nose pads can damage the skin around the bridge of the nose. Therefore, try to choose a silica gel nose pad and other soft materials. The first one is that the silicone has good softness and will not damage the skin. The other is that it can fit perfectly with the bridge of the nose without foreign body feeling.
How to Choose Glasses for Long Face?
Bold shapes and eyeglasses with decorative details are also a smart choice since they help draw attention to your eyes and can add width to your face. Be sure to avoid narrow or rectangular shapes, which can make your face appear longer.
Square glasses: if you have a long face, you can try square glasses whose sharper corners can help to balance out the length of your face and complement your narrow features. Choose frames that are slightly wider than your cheekbones to make your face appear broader.
Two-toned glasses: if you have a long face shape, the two-toned glasses would be a good choice. The color-top frames create an optical illusion that draws focus upward toward your eyes rather than to the length of your face.
How to Find Reading Glasses Strengths?
With the increase of age, your vision may begin to decrease and this is an inevitable change in your life. So, when you are trying to decipher some smaller prints, you may need the reading glasses.
When your vision begins to decrease, do not worry, this is a normal change. You will find that the deterioration insight often occurs around the age of 40. The technical term for this condition is called presbyopia, a natural, age-related change in the lens of the eye which makes it more difficult to focus on smaller print and close-up objects.
The condition may become worse as you are near 60 years of age, depending on the type of near distance tasks you performing. Of course, you also need to consider the actual situations.
Powerful Function of Lens From KOALAEYE
The lens is flat with high clarity. The glasses have an anti-scratch coating, an anti-scratch coating on both sides of the lens, which can effectively reduce the wear of the lens and prolong the service life of the glasses. However, the scratch-resistant coating is not 100% scratch-free but is more scratch-resistant than uncoated lenses. They have Super Hydrophobic coatings, Oleophobic coatings, and ultraviolet protection functions. Glasses are not only fashion accessories but super weapons to protect eyes and restore clear vision.