Choose rectangular glasses based on the shape of your face.
If you belong to the oval face, do not choose the too large or angular glasses frame. And do not choose long or square ones. It will be easy to elongate the face and affect the overall appearance. The shape of a round face is the opposite of a square face, so the buying principle of the glasses is basically the opposite of a square face. You need a more angular one to improve the shape of the face, but you need a square face (elongate) principle, that is, use a lower height, higher temple position of the frame.
The material of the nose pads
There are many differences between silica gel and PVC materials. For example, silicone can pass ROHS certification and is environmentally friendly. Silica gel is soft and feels good, while PVC products are rough. Silica gel products are soft, while PVC products are hard. Silica gel products are more flexible, but PVC has no toughness. Silica gel products are usually made to be more transparent. Glass frames made of plate material and TR-90 material, are relatively not heavy and non-allergic. Typically, the TR90 frame is cast to form a nose pad attached to the glasses ring. As the plate frame is cut out from compressed materials, the plate frame with a nose pad is usually injected into the nose pad after the frame is made.
PRiSMA blue light blocking glasses
PRiSMA is a functional anti-blue light glasses brand introduced by Germany to the world. Since its establishment in 1993, PRiSMA has been selling well in 33 countries and regions around the world. They use OAR double-layer coating technology to reduce reflection and increase penetration index. Ensuring a high blue light barrier at the same time, they increase the color contrast, so you can see more clearly, and effectively relieve eye fatigue. The product can protect the retina and relieve visual fatigue. They regulate melatonin secretion or reduces visual stress.
What is cellulose acetate?
Cellulose acetate refers to a thermoplastic resin obtained by esterification with acetic acid as a solvent and acetic anhydride as an acetylating agent under the action of a catalyst. It is the first commercially produced and continuously developed fiber among cellulose derivatives. Vegetarian organic acid esters.
About industrial pure titanium
For the industrial pure titanium, titanium content is not less than 98%, containing a small amount of oxygen, nitrogen, hydrogen, carbon, silicon, and iron impurities such as dense metal. The labels are TA1,TA2,TA3,TA4. It's arranged by more and more impurities. The TA1 titanium content is more than 99.5%, and the price is not high. But no matter which links, for molding, welding, polishing, processing difficulty is very great.The price of almost all titanium alloys in the national standard is higher than that of pure titanium.
In reality, the price of β titanium is higher than pure titanium. Pure titanium is almost no elastic, but β titanium is not only elastic, and has the advantages of ultra-light corrosion resistance. β titanium does not have a specific composition. Memory titanium can cost tens or even tens of times as much as pure titanium.
Using memory alloy to make glasses frame is the use of its superelastic characteristics at a certain temperature (elasticity is several times that of stainless steel) and did not use its memory function. Compared to beta-titanium, memory titanium is so difficult to process. It is so elastic that shaping is difficult and impossible at room temperature, and memory titanium heat treatment is another difficult and even secret process.
Why are eyeglass frames are so expensive?
Plastic frames are often used for rimless glasses, but they are not very resistant to corrosion and break easily. The plate is a new type of plastic, and it is light and has high hardness, not easy to deform, but the surface is easily corroded by sweat. TR90 has features of wear resistance, good chemical resistance, solvent resistance, weather resistance, not burning, high-temperature resistance. Plastic steel does not contain any metal, but it is a kind of high-strength molecular material, lighter than TR90. They have a higher level in corrosion resistance and strength and other aspects. The frames made of good materials are more comfortable, durable, and textured in daily wear, and will not cause skin allergies. Plate, titanium, TR90, alloy are the most used materials on the market at present. The price is in dozens of yuan to hundreds, thousands of yuan.
What Is Bifocal Lens?
Changes in vision seem to be related to age. Presbyopia, a common eye condition that occurs in middle age, causes changes in your eye’s ability to focus. But this condition can be corrected by wearing bifocal glasses.
Bifocal lenses are divided into two parts to accommodate two different prescriptions in one lens. One area of the lens will have one prescription (usually distance) and a segment in the lower half will have the other (usually near vision).
The bifocal glasses were invented by Benjamin Franklin, who solved his own vision problem by taking the lens from his reading glasses and distance glasses and cutting them in half. Then remade the cut lenses into a single pair of bifocals and put the distance lens on top and the reading lens on the bottom.
