Can Pinhole Glasses Improve Your Vision?
The most important question may be whether the pinhole glasses improve your eyesight and some people may have this trouble. Some people say pinhole glasses can improve the vision of nearsightedness or astigmatism. But there is no evidence to prove that.
Although pinhole glasses can improve vision to some extent, they are not practical for everyday use. Pinhole glasses are designed to block part of your direct vision and restrict peripheral vision. They would cut the amount of light entering your eyes so as to reduce the visual quality of an image. Hence, it would be not recommended to wear pinhole glasses in daily life.
What is a photochromic lens?
Photochromic lenses are lenses that become dark when exposed to a particular wavelength of light (usually ultraviolet light), but return to their original transmittance and become clear when no longer illuminated by the light source. Photochromic lenses can be made of glass or resin. The discoloration effect is caused by silver chloride or other halides added to the lens, which are transparent to visible light when not irradiated by ultraviolet light. When irradiated by ultraviolet light, chemical reactions will occur, which will absorb part of the visible light and make the lens show dark. The chemical reaction is reversible, so the lens returns to its original transparent state when it is no longer exposed to UV light.
Who needs computer glasses?
Blue light radiation from computer screens and so on usually only requires a piece of fiberglass to block, usually, we just use the anti-radiation glasses. Office white-collar workers often spend more than 8 hours a day working in front of a computer, and sometimes they spend their entertainment with a computer after going home. After long, the eye often can feel dry, sour bilge, ache, shed tears even, giddy. These are all related to the blue light stimulus emitted by the screen.
What is an aspheric lens?
Strictly speaking, any lens with a refractive surface that is not a sphere is an aspheric lens, including ordinary astigmatism lens, progressive multi-focal lens, Aspheric apical lens, etc. But customarily, our daily aspheric lens refers to the Aspheric apical lens. From the center of the lens to the periphery, the radius of curvature increases (the surface of the lens flattens out).
How to Test Computer Glasses (Clear Glasses)
First, we will show you how to test computer glasses with clear glasses.
1. Ask for Blue Light Glasses Brand Spectrum Report
To find out whether your blue light glasses are the best computer glasses, you should contact the company you bought them from and ask for a spectrum report. It will show you how much blue light your computer glasses can block.
After sending the spectrum report to you, you should make sure that your computer glasses are able to filter at least 30% blue light, otherwise, they are unsafe.
2. Use the Lens Reflection Test
As for how to test computer glasses, you can use the lens reflection test. You can see what color the light is that reflecting off the lenses.
If it reflects the blue light, they are filtering some blue light. If the reflection is violent or purple, the computer glasses may be not effective.
This is a good way for you to perform a blue light test at home.
How to Choose Glasses for Big Heads?
In this section, we will show you how to choose an eyeglasses frame for large heads. If you do not know how to choose, keep on your reading to find some solutions.
Rectangular frames: Rectangular frames add angle and can slim down the appearance of a larger head. So, if you have a big head, try the rectangular frames glasses.
Oversized frames: if you have a big head, the oversized frames would be a good choice. Oversized glasses will balance out your larger features.
Wayfarer frames: whether your style is retro or geek chic, you will find a perfect fit in trapezoidal wayfarer. The thick angular frames offset rounder cheeks and draw attention down from the forehead. So, if you have a large head, try this style.
When choosing glasses for large heads, you should also find the right shape and color for your signature look and style. While there are a lot of glasses styles for big heads, you should consider glasses with long enough temple length, the length between the hinge of your frames and where they bend around the ear. This measurement is critical for overall comfort, especially on your temples and near your ears.
So, from the above information, you have learned how to choose glasses for big heads.
What Do the Numbers on Glasses Mean?
The first number on glasses frames is the eye size. It is the horizontal width of the lenses. In general, the number of eye sizes varies from 40 mm to 62 mm in most of the spectacle frames.
The second number is the bridge size. It is the distance between the lenses. Also, it is the bridge that rests upon your nose. Mostly, the size of the bridge on glasses frames would be from 14 mm to 24 mm.
The third number is the temple length. It is the length of the stems of the frame that rests upon your ears. It can be measured from hinge to the end tip of the temple. In general, the temple length in most cases is from 120 mm to 150 mm. The bridge and temple help the frame to comfortably fit on the face.
Meanwhile, if there are no numbers on glasses frames, do not worry. You can always measure your eyeglasses frame with a millimeter ruler. Sometimes, the tiny numbers are worn off or sometimes they are printed too small that you might have to use the magnifying glasses. If you have known the glasses numbers meaning, you can choose to measure them by yourself.
At the same time, to fit the glasses better, you can also choose to measure your face for glasses frames. After knowing the suitable size of glasses, you can choose to buy a pair of glasses online. Thus, Koalaeye Optical is recommended. It is an online glasses store and provides all kinds of glasses, sunglasses, and frames. What’s more, these glasses are stylish and cheap.
