Advantages of aspheric lenses
In reality, aspheric lenses were originally born to improve the marginalized optical properties of spherical lenses. The aspheric lens with special coating treatment has perfect visual performance, with a clearer, more comfortable visual effect. You can hardly feel the presence of aspheric lenses when you put them on. So you can enjoy the ease brought by aspheric lenses. They are more natural and more realistic, having less visual distortion. The aspheric lens can be designed with a flatter base arc, which not only makes the appearance beautiful but reduces the peripheral magnification so that when others look at the eyes of the people who wear glasses, the size will not change much.
What Are High-Index Lenses?
High index lenses are eyeglasses lenses that are designed to be thinner and lighter than regular lenses. High-index lenses have a high refractive index than their conventional counterparts. So, they are generally recommended for people who have significantly high refractive errors and strong prescriptions for nearsightedness, farsightedness or astigmatism.
High-index lenses correct all types of refractive errors. And they are also available as single vision lenses, or a reading prescription that corrects presbyopia, such as in a bifocal or progressive lens.
High-index lens has a higher refractive index and which is ranging from 1.53 to 1.74. A lens with an index of 1.74 could be up to 50 percent thinner than a regular plastic lens with an index of 1.50.
Why Do My Glasses Give Me a Headache?
Why do my glasses give me a headache? There are a lot of reasons for new glasses headaches. So, in this section, we will list some of them.
Muscle strain: each eye contains six muscles. Since your eyes learn how to view the world through a new prescription, these muscles have to work harder do differently than they did before. So, this action may cause muscle strain within the eye and a headache. If you are wearing glasses for the first time or if your prescription has changed significantly, you may be prone to this effect.
Multiple lens power: if you have changed to a multiple lens power of glasses like bifocal glasses, varifocal glasses, it may be difficult to adapt in a short time. So, this change will lead to some problems such as headaches.
Poorly fitted frames: as for the issue of new glasses headaches, if you glasses fit too snugly across your nose or cause pressure behind your ears, you may get a headache. So, when purchasing a new pair of glasses, selecting a fitted one is important.
Wrong prescription: why do my glasses give me a headache? It can be caused by the wrong prescription. If your eyeglasses prescription is too weak or too strong, your eyes will become strained causing headaches. So, if you still suffer from headaches after wearing the new glasses for a few days, contact your eye doctor and check the prescription again.
The Disadvantages of Aspheric Lenses
Here, we will show some disadvantages of aspheric lenses.
The aspheric lens has a relatively small light area. When the eyeball rotates around, it will blur a little when looking at the outside through lens edge. In other words, the visual range of the line of sight becomes smaller.
Human’s eyeball is spherical and the eyeball rotates to the edge. Through aspheric lenses, the objects near the eye appear protruding.
What Is Plastic Lens?
In the above part, we have introduced what polycarbonate lenses are. In this section, we will show you what the plastic lens is.
The plastic lens was first introduced in 1947. Since then, plastic has become a popular and widely used material for making eyeglasses lenses. Since the introduction and use of plastic lenses, it has sealed its mark as the most preferred choice in the optical industry.
Plastic lenses are light. With this feature, plastic lenses are popular because they will not be heavy inside the glasses frame and permit for an easy fit in any type of glasses frame. In addition, plastic glasses are cheap and easy to obtain in desired amounts. So, they are affordable for most people. Plastic lenses are very durable. So, they do not shatter easily on impact which makes it a great choice for individuals who are active or tend to drop their glasses often.
However, compared with other lens materials, plastic lenses are usually thick due to their low index of refraction. The soft feature of plastic glasses makes them susceptible to scratching from a sharp object and why scratch-resistant coating is applied to form an additional protective layer. Plastic lenses do not provide ultraviolet protection.
Transitions® Photochromic Lenses
When you step outside, it immediately begins to darken. The lenses help prevent harmful blue light from digital devices, screens, and sunlight to help reduce glare and prevent eye strain. They have the function of 100% UV blocking,anti-reflection treatment with blue light protection. They can constantly adapt to changing daylight conditions to reduce excess light and optimize color contrast and polarized light to prevent dazzle. They filter out excess light to provide maximum comfort. And provide high contrast and minimize glare. They provide increased color recognition and depth perception.
The material of the nose pads
There are many differences between silica gel and PVC materials. For example, silicone can pass ROHS certification and is environmentally friendly. Silica gel is soft and feels good, while PVC products are rough. Silica gel products are soft, while PVC products are hard. Silica gel products are more flexible, but PVC has no toughness. Silica gel products are usually made to be more transparent. Glass frames made of plate material and TR-90 material, are relatively not heavy and non-allergic. Typically, the TR90 frame is cast to form a nose pad attached to the glasses ring. As the plate frame is cut out from compressed materials, the plate frame with a nose pad is usually injected into the nose pad after the frame is made.