Who are suitable for progressive lenses?
A progressive piece is suitable for most old people to wear. The proper person is the one who has the visual needs of the long, medium and short distance cares about beauty, and is willing to accept new things. In order to avoid binocular vertical prism differences, for the wearer whose equivalent spherical lens with anisometropia is more than 2D, especially if the difference in refractive power of the vertical meridian is more than 2D, it should be checked with caution. Opticians whose vision needs do not match the progressive lens design, like dentists, often experience blurred vision when working with the far side of the lens to look closer.
Why are rimless glasses so expensive?
Rimless glasses are the design vantage point in the frame of glasses. The structure of rimless glasses requires many higher physical features (flexibility, surface texture, etc.) and machining accuracy than TR, PEI, and other materials. In order to ensure comfortable wear, the common materials are very exquisite. And for processing technology, the frame is the most difficult. It's not just grinding, it's a full polishing, and it's perforating. This is the technical demand and the most time-consuming.
Advantages of Metal Frames
The metal frame of eyeglasses conforms to the use performance of the frame. They need the material to have high fracture strength, enough plasticity, toughness, and good elasticity. And after the disappearance of the external force, they can restore to the original shape. This is the regular demand for the high elasticity of the metal frame. They must be able to withstand the atmosphere and human sweat daily corrosion. Usually, the corrosion resistance of pure titanium eyewear will be better than other eyewear. Some glasses will have a variety of wonderful grinding designs, and the material must have high plasticity.
Buy Prescription Glasses Online Step By Step
1. Before you can buy glasses online, you’ll need a current glasses prescription.
2. Select an online retailer, comparing online retailers like EyeBuyDirect and KOALAEYE until you find the best fit for your needs.
3. Shop for the perfect frames according to face shape, frame favorites, the budget, etc.
4. Once you’ve found your perfect frames, you’ll enter your eyeglasses prescription and pupillary distance to choose the lenses.
5. Read over the fine print on return/exchange policies and product warranties before you complete your order.
6. Having picked your perfect frames, entered your prescription information, added any lens coatings and upgrades, and checked your online retailer's warranty and return policy, it’s time to complete your order.
What are prescription computer glasses?
Prescription computer glasses are prescription glasses designed to do computer work. They allow your eyes to focus on the computer screen, which is farther away than reading material would normally hold. These special glasses are designed to meet the visual needs of the movement.
How To Choose Better Night Driving Glasses?
Driving at night has a high accident rate because of poor visibility, blinding headlights, and fatigue. Now the market exists a few main glasses: sunglasses polarizing lenses, Glasses that use or mimic the first generation of patented technology. So how do you compare the options between driving and wearing glasses?
Night driving lens is relatively special compared with daily driving lens, not only to prevent strong light and see the road more clearly. According to the national motor vehicle driver special glasses standards, QBT 2659-2004 daily light transmittance should be more than 8%, night light transmittance should be more than 75%. Be sure to consult customer service. Ask about the situation. Note that a pair of polarized sunglasses are not suitable for use at night, and the light transmittance must reach the national safety standards.
The Disadvantages of Polycarbonate Lens
In this section, we will show you the disadvantages of polycarbonate glasses.
First, the polycarbonate lens is expensive than other regular lenses. It can cost up to double the price of regular eyeglasses.
Second, compared with high-index lenses, polycarbonate glasses have a lower abbe value, which is used to measure the dispersion of light for different eyeglasses lens materials. Polycarbonate lens rates lower mean they have the potential to cause slight chromatic aberrations in your peripheral vision.
Third, compared with Trivex lens, polycarbonate lens has bad durability since they are thinner and lighter.