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.
Safety effects of non-prescription glasses
Safety glasses are available in a variety of styles for different users. There were glasses to protect his eyes from shocks or damage, like those used by people who lost an eye in the past. Many of them often wear protective goggles to protect their eyes from injury and to maintain a degree of vision. Safety goggles made of shatter-proof materials have become a staple in many industrial places, from factories to construction sites. Because in such an environment, the likelihood of being hit by debris or mud is very high.
Can you wear blue light glasses while driving?
The damage of blue light has a cumulative effect. The longer the exposure time is, the more serious the damage of retinal cells will be, which will eventually lead to irreversible damage of the structure and function of the retina. Once the retina has permanent damage, degeneration will directly affect the metabolism and function of photoreceptor cells, resulting in vision loss. It depends on the glasses you're wearing. The function of anti-blue light glasses depends on the material of the glasses. Some blue light glasses have a special anti-reflective coating, which can reduce glare. These glasses are definitely helpful when driving at night.
A saddle bridge is a type of bridge.
The bridge of the nose can make your nose look slimmer. There are two main types. The keyhole distributes the weight of the glasses to one side of the nose rather than the top. It's a good choice for those with a broad nose. The Keyhole Bridge is old-fashioned in the classic style, like a Keyhole. This design creates a small gap in the top part to give the impression of space, thus making your nose look smaller. Saddle bridge is a more modern style and usually goes around your nose with almost no gaps at the top. This close contact will make your nose look tighter.
How to buy anti-blue light products?
In order to further standardize anti-blue light products and make all kinds of products effectively protect eye health, relevant standards have been formulated. Based on the different effects of blue light in different bands on the human body, the transmittance of blue light in each band is required in the standards.
For example, in the band range of 415-445 nm, the transmission ratio of light is less than or equal to 80%, and more than 445 nm, it is greater than 80%.
Advantages of Plastic Frames
Plastic frame material is mainly various types of plastic polymer materials. With the characteristics of impact resistance, suitable for athletes to wear. The plastic used to make the frames can usually soften under the condition of the heating, and some plastic frames can be fine-tuned without heating. The plastic frames are not allergic and lightweight, making them suitable for children and people of all ages. And because the color is rich, and there are many styles. They become the choice of fashionable sunglasses. Plastic frame cost is low, and the process is simple. Because of its lightweight, plastic glasses frame is not easy to allergy. Because of its color and material characteristics, they become the fashion personage sunglasses or decoration choice.
Step-by-Step Glasses Size Guide
In this section, we will show you how to perform glasses measurements. But the first thing is to know what face shape you have. If you do not know, click here to have a check.
Then you need to know where to find the size measurement of your glasses. In general, you will find numbers that look like this 51-17-145 at the temples of your eyeglasses. Of course, these numbers come at different meanings.
The first number often refers to the lens width. Lens width is the horizontal diameter of the lens at its widest point. In optometry, another term is eye size.
The second number often means the bridge width. Bridge width is the part that joins the two lenses and sits over the nose. Some refer to this as the gap. The bridge width varies between 14 and 24 millimeters.
The third number often means the temple length. The temple is the arm that keeps the sunglasses on your face. That arm extends to the part that hangs on the ears. The length is usually 135, 140, or 145 millimeters.
Lens height measures the size of the lens vertically, that is from the top to the bottom of the lens. Although sizes may differ depending on the brand, the standard size is somewhere between 32 and 38 millimeters.
