Keyhole glasses are different from saddle glasses.
Glasses without nasal pads are common, usually with plastic eyewear frames and metal frames. Plastic frames without nose pads usually have a saddle-shaped nose area, therefore this type of bridge is called a saddle bridge. The keyhole is designed to touch the two points of the bridge of the nose, eliminating pressure from the top of the nose. This style is a bold fashion statement for both men and women. The design has short pads on either side of the nose, which is thought to be the most comfortable area.
A round face fits on a square frame.
The human face of a round face is shorter. So they had better match the slender frames that take curves slightly to reconcile the whole feeling. Angular and square frames are helpful to modify facial lines (prominent longitudinal lines). This can promote strengths and avoid weaknesses so that your face appears contour.
Different Types of Progressive Lenses
The first progressive lenses we want to introduce are computer progressive lenses, which are designed for clear vision in office settings. These lenses are ideal when using a computer for over 4 hours a day and help to reduce eye strain.
Computer progressive lenses are intended for indoor use and should not be worn over your regular glasses. The drawback to this is it requires you to have two separate pairs of eyeglasses.
Sunglasses
Sunglasses have a visible light transmittance of about 20% and can absorb ultraviolet and infrared rays well. It also has a variety of colors such as light green, light gray, light brown, etc., used to protect in different occasions. Among them, light gray lenses have little effect on color recognition. Light brown glasses make the blue sky look darker and reduce the transmission of green light. Light green lenses reduce the transmission of red light.
Sunglasses not only have a wide range of varieties, but with the improvement of decoration and health care effects, their scope of use has become more extensive. As the time to update sunglasses can be rapid, fashionable men and women would love to have multiple sunglasses to match clothes to satisfy their pursuit of fashion.
What are the causes of lens damage?
When the force area of the lens is small, the impact resistance of the lens is worse. When subjected to the impact of external forces, the lens will naturally be squeezed and cause breakage.
In particular, some lenses with low degrees and high refractive index are possible to cause this phenomenon. When the frame fell from a height due to wrong placement, there is a collision between the edge of the lens and the ground or hard objects. It will produce a broken or collapsed edge. In the process of the lens falling from high, the impact force is larger, and the stress point is smaller. When the glasses are falling, the upper edge of the lens, the convex groove of the upper frame, squeezes against the lens. The middle part of the upper half is easy to cause edge collapse. In the process of processing the template, the template is not accurate, so that the glasses side and the frame can not be uniform fusion, and the force of the lens is uneven. It will be easy to lead to greater stress in some parts, resulting in edge collapse.
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.
Cheap frames can cause skin irritation.
Some cheap frames may look like more expensive frames. But more often than not, they are made of low-level materials that can cause skin irritation over time. Cheap plastic frames can be bleached by ultraviolet light, leaving the surface rough after months of wear and tear. Cheap metal frames often contain nickel alloy, which can cause skin irritation.
