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.
Contact Lens Materials - Non-HEMA materials
The non-HEMA materials are hydrophilic soft lens material, which does not contain HEMA components. They are stronger and more oxygen permeable than most HEMA polymers.
The water content of regular hydrogel lenses varies from 30% to 58%. When oxygen passes through the hydrogel, it needs to be carried by water molecules in the material. Therefore, the higher the water content of the lens, the higher the oxygen permeability value. The softer the lens, the more comfortable it is to wear, which is conducive to the metabolism of the cornea. However, at the same time, the higher the water content of the lens, the faster the water evaporation, easy to dehydration, and easy to cause dry eyes. A lens with high water content has low material density, poor durability, and easy breakage, so they are suitable for making lenses that are frequently changed or discarded. On the contrary, the lens with low water content has good formability, easy operation, durability, and is not easy to dehydrate and cause dry eyes.
What Are Trifocal Lenses?
When you are over 40 years old, your eyes may become old, too. Your corrective lens requirements may become increasingly unique, Most people are familiar with bifocal glasses but unfamiliar with trifocal glasses. So, in this post, we will show you what trifocal glasses are.
Trifocal lenses have three different corrective lenses within one lens to offer you intermediate, distance, and near correction, all in one pair of glasses. The varying levels of correction cab are laid out in a couple of different ways to ensure the layout suits your unique vision needs and comfort level.
The near vision is to correct close-up vision, the intermediate vision is often used for card playing and staring at the computer screen fall with this range of vision, and the distance vision is often used for driving or looking at a whiteboard.
How To Use Contact Lens Correctly?
It is not recommended to use contact lenses when they are dry. Because when they are dry, even the nursing vacuole is used, the parameters change. It will affect the comfort of wearing, so it is recommended to replace the new lens. After the nursing liquid is used every time, you should cover the lid tightly. Do not touch the mouth of the bottle with your hand. If expired and unused, it should be discarded and replaced with new nursing fluid. As for your discomfort, you should return to the store for inspection.Contact lenses and glasses should be used interchangeably.
Geek 111 Glasses
The Geek111 is a unique, yet timeless frame containing decorative metal plaques. The metallic trim makes it a stylish combination, and for this frame, there are several different colors to choose from, including black, brown, and gray. They can easily add anti-reflective coating and/or different lens colors so you can be more confident when driving at night.
Beta Titanium Eyeglasses Rimless Flexible Optical Frame
These are Beta titanium rimless flexible optical glasses. Free delivery around the world is provided! Many colors like Gold, black, gray, red, brown, pink, blue, purple are available. They choose high-quality materials. There are high-quality photos and real customer reviews. They have different kinds of sizes, and affordable products are provided.
Types of Optical Frame Glasses
The full-frame glasses have good strength, suitable for athletes and children to wear because the lens is completely protected by the lens ring. They are suitable for a variety of refractive parameters of the lens. The upper part of the lens ring is made of metal or plastic materials. The lower half of the lens ring is made of a very fine nylon wire like the lower part of the lens ring. Rimless glasses are lighter than full-frame glasses. Rimless glasses can be divided into parts type and integral type. The part type consists of a nose bridge (together with the nose pad) and two temples. The combination glasses are divided into two parts. Usually, the front group is equipped with colored lenses, and the rear group is equipped with lenses for correcting refractive errors. The folding glasses can usually be folded at the bridge of the nose and the temple to reduce the space when stored or carried and are mostly used for making reading glasses.
