What is a qualified plano lens?
First, identify the surface. High-quality products should not have obvious scratches, pitting, edge collapse, sand holes, water ripples, bubbles, and other surface defects. Put glasses next to the place of 33 cm or so at the moment. When looking at the object through glasses, there is no phenomenon that the objects become big or decrescent, and you should not have a feeling that the objects are beating. Otherwise, the quality of the glasses has a problem. Next check through the instrument identification. Finally, check whether the trademark, manufacturer, and quality certificate are true and reliable. The lens of the international famous brand product is often engraved with the manufacturer's trademark, which can be found by careful observation on the edge of the lens.
Keyhole glasses are different from saddle glasses.
Glasses without nasal pads are common, usually with plastic eyewear frames and metal frames. Plastic frames without nose pads usually have a saddle-shaped nose area, therefore this type of bridge is called a saddle bridge. The keyhole is designed to touch the two points of the bridge of the nose, eliminating pressure from the top of the nose. This style is a bold fashion statement for both men and women. The design has short pads on either side of the nose, which is thought to be the most comfortable area.
Why does shape memory alloy have memory ability?
It starts with its microstructure. When a metal is solid, its atoms are always arranged in a regular way, forming a lattice. Under different conditions, such as temperature, metal may have a different structure, in which case it is said to be in a different phase. The change from one phase to another is called a phase transition. The properties of a metal change during a phase transition. The temperature at which a metal transforms is called the transition temperature. The difference between a shape memory alloy and other metals is that the phase transformation process in a shape memory alloy is reversible under certain conditions.
Which face types are suitable for rimless glasses?
Rimless glasses are mainly suitable for round faces, heart-shaped faces, square faces, and other most face shapes. Rimless frames are designed to be light, hence, they ease the wearer's stress, increasing comfort, and providing a wide view. Rimless glasses suit most face types, suitable for people who are short-sighted within 600 degrees. If the degrees are too high, you should not wear rimless glasses. When the degrees are too high, the lens will be suitable for thickening, so rimless glasses will show bloated.
How to Pop Lenses Out of Glasses with Plastic Frames?
In this section, we will show you how to take glasses out of plastic frames. It would be much easier to remove lenses from plastic frames because lenses are not fitted as tightly in them as in metal frames.
Now, here is the tutorial.
- Many plastic lenses will come out easily as you push through your thumb from the inner side and fix your fingers on the other side.
- If they do not come off, you can choose to heat the plastic a little bit so that it expands and allows the lenses to come out.
- To heat the plastic frames, you can immerse the glasses in a bowl of hot water. The water should be hot, not warm but of course only as much as you can handle amicably.
- Be careful to not drop your lenses in the bowl. Dry them with a no microfiber cloth and then you can remove them. You can’t use any towels because those can damage any blue light or anti reflective covering.
After all steps are finished, you can remove lenses from glasses.
Glasses Size - Bridge Width
The bridge width is the distance between two lenses, measured from the innermost layer of each lens. Finding the right bridge width will allow your sunglasses or glasses to be put properly on the bridge of your nose. The bridge of the nose is an essential element because even though the frame looks pretty attractive, it helps people see more clearly. The precise distance between the two lenses helps reduce the pressure on the eye, helping the nose, without putting too much pressure on the inside of the eye. The size of the eye and the size of the bridge is usually adjacent, sometimes separated by a square icon.
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.
