The fabric of eyeglasses cloth
Ordinary fabric: They are only applicable to the surface that has been cleaned.Because the ordinary fabric has no space to accommodate dirt, the surface of the cloth will be very dirty, and difficult to wash clean.
Microfiber fabrics: They are used wet to emulsify dirt and oil, and the microfiber is easier to wipe off. It is highly absorbent, making it very quick to clean the spilled liquid.
Fine fiber double velvet fabric: It feels soft, gentle, with the plump texture, but more single velvet.
Suede fabric: The feel and appearance are quite like natural suede, fine and smooth, soft and plump, used to wipe glasses. It will be clean and won't scratch the lens.
Data obtained by computer optometry alone may not be accurate.
The first thing is to go to the optometry store, or the hospital to do a glasses degree test, namely to get single optometry. The precision computer optometry has errors, and computer optometry is only used to measure separately monocular degrees. What we need is the best visual effect of the binocular match, so the exact prescription needs to be carefully confirmed by comprehensive optometry. Optometrists will ask everyone to try on the insert lenses again, and even need to repeatedly try on several degrees of lenses, in order to finally determine which degree is the most appropriate, because even the professional optometry data is only a rough range, only based on the data of glasses is not necessarily suitable for their own. You can use a focometer to measure the actual parameters of the glasses you are wearing. If you are still unsure of your prescription, it is recommended to fax, mail, or mail your prescription to the merchant when placing your order.
Choose the right clear sunglasses for your face shape.
A clear eyeglass frame suits the person of different face shapes according to different shapes. For example, a heart-shaped face suits the clearest eyeglass frame, and a square face suits an elliptical transparent eyeglass frame. A round face suits the clear eyeglass frame with an outline. The long face suits the clear eyeglass frame with some width and so on. There are many kinds of clear frames, like oval, round, square frames, and so on.
When choosing clear frames, be careful to choose one that fits the shape of your face. Oval and the round clear frame are more suitable for heart-shaped faces, square faces, and long faces. People with round faces should avoid large frames, dark frames, and wide edges, and don't wear round or square frames.
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.
Understand the impact of frame selection on the lens
Frame size is an important consideration when using progressive lenses because some progressive lenses work better in frames of different sizes. Since progressive lenses allow you to see at all distances, it's important that the whole range of vision fits within the frame. Therefore, very short lenses and larger lenses are not suitable for progressive lenses.
How do you identify the refractive index of lens?
In reality, this problem is often a problem for optical shop practitioners, sometimes they worry about whether the manufacturer's lenses match the nominal value of the refractive index. We need a prop, and that's the camber. Because it can be used to measure the strength of the lens. The luminosity of the lens can be calculated by subtracting the curvature of the inner and outer surfaces of the lens. The curvature difference of a lens of the same luminosity is inversely proportional to the refractive index, that is, a lens with a higher refractive index only needs a smaller curvature difference to achieve the same luminosity.
The Types of Blue Light Glasses
Computer Glasses - Clear Lenses
First, we will show you the computer glasses which have clear lenses, These glasses are made to be used when working on your computer, smartphone or while watching TV. The best computer glasses can filter 5-30% of all blue light.
Night Driving Glasses - Yellow Lenses
When driving at night, the blue light glasses with yellow lenses would be suitable. These blue light lenses are good at removing more of the highest energy blue light, around 440 nm and they are also able to distinguish traffic lights when driving at night. These glasses can block around 65-70% of blue light.
Blue Light Glasses for Sleeping - Red Lenses
The blue light glasses for sleeping have red lenses. The best blue light glasses come with red lenses and they block 99.5%-99.9% of all blue light and a large amount of the green light spectrum, from 495-550 nm.
After knowing the different types of blue light glasses, we will show you how to perform the blue light glasses tests.
