There are three processes for resin-changing lenses.
The incorporation method, known as bulk polymerization, is similar to the method of glass lens, that is, one or more photochromic dyes are directly incorporated into the polymer monomer of the substrate for bulk polymerization, and the lens formed after curing will change color. Discoloration dye is completely integrated into the resin lens substrate, so the lens made of color persistence is very good.
The uniformity of discoloration and the depth of color after discoloration are highly related to the thickness of the lens. Because the thickness of the lenses at all levels is different, there will be a color difference between the depth of discoloration and the uniformity, and the uneven phenomenon of high brightness is more obvious.
The film type is known as the coating method. It is the chromatic resin lens by coating or dipping in a layer of chromatic dye on the base of the resin lens. Because the coating covers the surface of the lens, the color uniformity is good. The coating, which is only about 0.05mm thick, does not provide enough molecules to make the lens dark enough, so the color is relatively less dark, and the discoloration lasts slightly longer.
Infiltration, known as the penetration method, is to use the principle of penetration, through the thermal diffusion method to make the color dye permeate the surface of the resin lens sheet material, with diffusion depth up to 0.15~0.20mm. The lens has a constant color change characteristic. There will be no inconsistency between the center and the surrounding color as the luminosity gets darker. The color-changing resin lens made by infiltration type has the benefits of uniform color-changing, small color difference, fast and thorough color-fading, which is the mainstream of color-changing technology at present.
Common Problems with Varifocal Glasses
In this section, we will list some common problems with varifocal glasses. The most common problem with varifocal glasses is people being unable to focus on what they need to. Losing focus often leads to some discomforts such as headaches or dizziness when performing tasks that require quick changes in near and middle-distance focus.
Besides, some people also experience a sort of swimming feeling when they are walking. It may be caused by being very aware of the distortions in your peripheral vision as well as the reading portion at the lower part of the lenses.
So, how to use varifocal glasses? The best way is to keep yourself from looking downward as you walk. You may also experience soft focus at the edges of the lenses and need to move your head more to see near objects better.
Men’s clear glasses frames
Some men like the classic eyewear style like aviator, wayfarer, or rectangle eyeglasses. If you would like to refresh your daily look, the clear glasses frames with the unobtrusive appeal will deserve your shoot. The clear acetate eyeglasses frame with a round shape makes these clear round glasses a good choice for men.
How to know if lens is polarized?
Make use of LCD screens. Point the glasses horizontally at the LCD screen and then rotate them upward by 45 degrees clockwise. If it is a polarized lens, it will show a change in color deepening. If it does not change no matter how you rotate it, it is not a polarized lens. You can borrow another person's polarized lens or have previously worn a known true polarizer, and place it crossover with the new glasses you want to buy. At this time, you should see the object clearly from the crossover part with your eyes. Then cross the glasses vertically and horizontally, and at this point, the opposite object should not be visible from the intersection. If this condition is satisfied, it means that a true polarized lens is being tested.
What is the best lens material?
Trivex is a special material from PPG. Compared with PC lenses, the refractive index is lower (only 1.53) but the Abbe number is higher (up to 45), which results in smaller dispersion and better image quality. At the same time, the impact resistance of the Trivex lens is 10 times higher than that of the PC. It is the only explosion-proof safety lens that can withstand external force twists and turns in the market at present.
How to drive at night with glasses?
If you need to wear glasses while driving, you'll need special glasses when driving at night, because common lenses reflect oncoming lights, which produces a faint glare. This will reduce your visibility. It's OK to wear contact lenses while driving. As you get older, your eyes become more sensitive to glare. Ordinary sunglasses or goggles are only suitable for wearing during the day, driving at night will seriously affect the vision (national standards stipulate that light transmittance of night driving glasses must be greater than75%). Although the all-weather driving glasses can weaken the strong lights, the vision darkens and affects road safety which does not meet the national standards for driving glasses at night. You should choose functional driving glasses that can block strong light, glare and increase the field of vision. This can effectively reduce the glare of the car lights but can filter out the extra harmful light. When worn at night, it can soften the strong lights and make the vision clearer. In this way, the safety of drivers is ensured, the fatigue of eyes is alleviated, and the radiation damage of harmful lights to glasses is prevented.
American Eyewear Brand - Ray-Ban
Ray-ban glasses represent a wild, rough and bold image, full of extreme masculinity. Ray-ban glasses, which are designed for PILOTS of the U.S. Air Force, look like American soldiers and give the wearer an aura of vigor.
