Testing of aspheric lens
The optical axis of the optical center just overlaps with the visual axis of the eye, which is the most ideal state. Because the light from the edge cannot form a focus on the optical axis, when the optical axis does not overlap with the visual axis (the difference is greater than 2mm), such unclear and scattered imaging results will occur. When choosing frames and aspheric lenses, you need to ensure that they fit correctly, to achieve the best visual and decorative effects. Simply put, due to the special design of the lens, we found through a calculation that the optical center should move down 1mm higher than the pupil for every 2° increase in front inclination angle. Otherwise, the wrong pupil height will cause the lens to look like astigmatism, and cause discomfort. For glasses with aspheric lenses, there must be an inclination angle after wearing. The specific angle varies from person to person.
What are bifocals?
A bifocal lens is a lens with two focal points. Because of the imaging principle of the lens, even half of the lens can still present a complete image, and the two images do not interfere with each other. In the past, both short-sighted glasses and presbyopia glasses were called single-focal lenses, which had only one focus. Later it developed to the bifocal lens, and the same lens is divided into upper and lower two parts. The upper part of that lens is used when seeing far, and you look down when seeing close objects, just the reading distance, naturally used the second half.
5 Unbreakable Eyeglasses Frames
In this section, we will list the most durable eyeglasses frames and we will introduce them one by one.
Titanium: One of the most durable eyeglasses frames is the titanium eyeglasses frames. It is lightweight, strong, and flexible. So, titanium eyeglasses frames have lots of fans in the eyeglasses market. In addition, pure titanium is hypoallergenic. But, due to these features, titanium eyeglasses frames are expensive than other frames.
Stainless steel: Stainless steel frames have some spring in them, which resists breakage. Stainless steel also resists corrosion, giving it a longer life. However, stainless steel eyeglasses frames may be hypoallergenic, depending on the alloys used.
Nylon: many people like athletes like nylon frames because they are flexible, lightweight and unbreakable - at least in the short run. However, nylon frames may become brittle over time, which is something to think about.
Kevlar: kevlar eyeglasses frames used in bulletproof vests can survive strong impacts, making them a good choice for contact sports and high-risk jobs. It does not have a lot of flex, limiting its applications.
Flexon: besides the above unbreakable eyeglasses frame, we will introduce another brand-name metal - Flexon. Flexon has a unique capability for springing back to its original shape after it gets twisted and they are called memory metal.
Gunnar Intercept blue light blocking glasses
The company is committed to improving people's visual experience when watching digital devices like computers, laptops, smartphones, pads, etc so that the wearers will no longer be affected by harmful light like short-wave blue light and glare refracting from these digital screens. They are continuously pursuing better protection of human eyes. Gunnar Intercept anti-blue light glasses filter or block harmful blue light from screens like computers. They relax eye muscles, soothe eye fatigue, prevent eye dryness, maintain constant moisture, and increase visual clarity.
How to Remove Scratches from Prescription Glasses with Coating
It would be an unfortunate thing if there is a scratch on your prescription glasses. Some people may ask how to remove scratches from prescription glasses with coating. Unluckily, there is no magic cure to remove scratches from prescription glasses. Once your glasses are scratched, they are scratched.
However, there are some products on the market designed to make the scratches look less visible. In fact, most of these products are just waxy substances that wear off easily and they even can smear anti-reflective lenses.
So, if your glasses are scratched, for optimum vision and safety, you had better replace your lenses if they become scratched. When purchasing the glasses, you can go to the local optical store or choose online. For example, the Koalaeye Optical is a good choice because it is cheap and has free shipping. You can find some professional explanations on this website, such as Sphere, Cylinder, or Axis.
Rimless Glasses 393014
They are not heavy, with a nose pad and spring hinge. It is a metal alloy frame, and it has a designer acetate temple. This pair of glasses show lens shape #226. These different lens shapes and selection of size can greatly change the overall look and final size.
Are Blue Light Glasses Bad for Your Eyes?
After learning some basic information about blue light blocking glasses, are blue light glasses bad for your eyes? No, the blue light glasses would not damage your eyes. Blue light blocking glasses can protect your eyes from harmful blue light and UV rays by using special lens technology to block and filter them out.
Sunlight contains the full spectrum of visible light including red, orange, yellow, blue, indigo and violent, and also non-visible light such as ultraviolet and infrared. A moderate amount of blue light and UV rays can be beneficial for us, but too much can damage our eyes.
