Qualified Optical Shop
Qualified opticians are determined not to sell substandard glasses. It is not recommended to keep the lens frames unless the same type can be found. If not, customers will be told directly that the data is likely to change. Optical shops using imported edge grinding machines can better ensure the accuracy of the data of the glasses. The processing engineer must pass a strict examination before he will process glasses for customers. And each pair of glasses needs another person to check, and then pass to the customer to wear. When customers take glasses, they should be informed of the correct steps for cleaning glasses.
Why do spectacle lenses fog up?
The fog on the surface of the lens is essentially related to the saturation pressure and water vapor liquefaction. The air is full of water molecules, which are constantly doing irregular movements. When there is no temperature difference, water molecules keep hitting the surface of the lens and will keep bouncing off. The lower the temperature, the slower the speed of movement. Therefore, when water molecules hit the cold lens from the hot air, on the one hand, they move too slowly to fly out in time. On the other hand, because of the relatively low temperature of the lens itself and its vicinity, the water vapor will liquefy. As a result, more and more water will accumulate on the lens and form small droplets, eventually forming a foggy layer. As the lens heats up, the mist evaporates back into the air, and the fog disappears.
Acetate cellulose pellets are extruded by an injection molding machine, which is called an injection frame. Its characteristic is that it saves raw materials, can be mass-produced, has a lower cost, and is cheaper than a plate rack. But the firmness is not as good as the plate frame. However, injection frames are mostly used for glasses for the elderly and children because of their lightweight and resistance to allergies. The injection frame is made of laminated plastic. It is made by pasting a thin layer of plastic of one color on another thicker layer of plastic. Thick materials are mostly transparent pigments. It is also made of three or more layers of plastic.
Can You Wear Glasses Without Prescription?
So, can you wear glasses without prescription? Of course, you can. You can wear glasses without prescription and they would not cause any damage to your eyes. What’s more, some non-prescription glasses, such as the type that blocks harmful blue light, can be beneficial to your eyes.
How Should Glasses Fit?
Make sure your pupils align correctly. The combination of frame, arm, bridge, and lens measurement can affect the placement of your pupils within your lenses, which is essential to the proper function and comfort of your prescription. To ensure glasses fit properly, the pupils should align horizontally in the center of your lenses.
Also, you should consider your face shape. When choosing a pair of suitable glasses, you should consider what face shape you have.