Do blue light glasses actually block blue light?
Anti-blue light glasses are still popular on the market. This kind of glasses is said to be 'anti-radiation and anti-blue light', but this kind of hot-selling anti-blue glasses has many problems. At present, such anti-blue glasses mainly block or absorb blue light through special materials, but there are two misunderstandings in its blue light protection. One is that the protection is not preventable, and the other is that the color cast caused by the wrong protection makes visual fatigue aggravated. Studies have shown that our eyes are the most intolerant of blue light in the 400nm to 440nm band. Therefore, current manufacturers mainly block blue light in this band when producing anti-blue glasses. But the electronic products that we often come into contact with nowadays produce blue light between 450 nanometers and 490 nanometers, and anti-blue glasses have almost no protection in this wavelength. Generally speaking, the blocking rate of anti-blue glasses is 20% to 30%, but now the blocking rate of anti-blue glasses on the market basically reaches 80% to 90%. This high blocking rate can also easily cause a color shift. , It is easier to make the eyes tired.
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.
The Identification of the Quality
The frame that has good elasticity is usually of better quality. The frame that has a smooth and shiny coating is better in quality. If the solder joint is smooth, small, and uniform, the quality is better. The parts of the sunglasses are assembled closely. The size and shape of the left and right lens must be the same, and the bridge of the nose must be symmetrical.
What is a drop ball test?
The Drop Ball Test, known as the Basic Impact Test, is an Impact Test administered by the Food and Drug Administration to determine the safety of eyeglasses. Eyeglasses (sunglasses, exercise glasses, near-sightedness glasses, reading glasses, etc.) are a category of medical devices covered by the Food and Drug Administration. When glasses are exported to the United States or put on shelves on Amazon,eBay, and other platforms, they need to be registered by FDA. Besides the product listing, when the product passes the customs, the company may be asked to produce a Certification Statement of Impact Resistance stating that the product meets 21CFR801.410 Drop Ball Test requirements.
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.
What Do Pinhole Glasses Do?
Pinhole glasses are often used by eye doctors who use them as a diagnostic tool to quickly check for vision impairments. Of course, pinhole glasses are sometimes used to treat nearsightedness or astigmatism. Pinhole glasses are also used in conjunction with an occluder, an instrument used to cover one of your eyes while you read an eye chart. The occluder is solid, while the pinhole glasses have a number of tiny pinholes. So, the doctor often uses it to check the potential of your vision.
Pinhole glasses are often used to check corneal distortion and cataracts. A cataract evaluation includes focusing light in the eye to check if vision capability behind the cataract makes it worth performing surgery.
Use them in exchange for a new pair.
A trade-in would be an excellent option. The old eyeglasses can be recycled by taking them to the optical shop, which is a low carbon and environmentally friendly.