Semi-rimless glasses are easier to clean and maintain
Semi-rimless glasses usually have only half of the glass frame. We tend to wipe our glasses in one direction, but we all know that the glasses are all wrapped up. So when some small particles appear on our glasses, these things can not be wiped out by the glasses cloth, and it is easy to scratch the lens. This is one of the drawbacks of full-frame glasses.
Buy Glasses For Kids - Proper Lens
The size of the lens mainly determines the size of the eyeglasses. The outer edge of the rim of the lens should be on the outer edge of the orbital bone. If it is larger than the face, the rim of the lens frame will be too big. If the lens is only as big as the eye, the frame can easily deform. Resin and hard lenses should be considered first because glass lenses are fragile and easy to damage children's eyes. Resin lens mainly needs the accuracy of the axis of scattered light. The matched luminosity must be accurate. There are no scratches, no bubbles, and no impurities on the lenses. The degree of the lens selected for the child must conform to the quality testing standards promulgated by the state, and the error of the diopter should be within the range of the requirements of the national standard.
How to buy prescription glasses online?
To buy prescription glasses online, you should get a prescription and visit your local optician for an eye test. This test can be used not only to provide a prescription but also as a regular health check. Ask the optometrist for this data if you have had an eye exam and the optometrist provides a prescription. If you have an extra pair of glasses, send them to an online eyewear retailer to make sure the lenses have the correct 'visual center.' Measure the pupil distance. Ask your optometrist for this number, or get it from old glasses. Choose the right frame style to suit your face shape. Understand the frame measurements. Choose a suitable lens and its different lens film layer. Then place an order for glasses.
Driver's protective glasses
The principle of the driver's protective glasses is to use the special film on the glasses to reflect the strong light hitting the glasses back to protect the eyes. It can protect against ultraviolet, infrared and blue light on foggy and rainy days. In snowy weather and at night, the wearer can see the scenery more clearly, and it can also increase the vividness of red, yellow, green, white, and other colors, and eliminate the glare and reflected light of the oncoming cars when meeting cars at night.
How do bifocal reading glasses work?
Bifocal reading glasses have two different lenses on the same lens. The top of the lens is your normal distance prescription, while the bottom is for close-up viewings, like reading. The two lenses allow you to alternate between them by moving your eyes up and down as needed. A bifocal lens is a type of lens that has two different areas of vision: one for close range and one for long-range. Typically, the upper section covers remote vision and the lower section covers reading. With a traditional bifocal lens, you can see the difference between the two lenses because the lower curve is a little different.
Do all glasses come with nose pads?
The glasses without the nose brace are plate glasses. In reality, there is still a nose pad, but it is relatively small and it's part of the frame. The westerners have high nose bridges, and many glasses have no or very small nose pads. For example, Harry Potter's glasses have no nose pads. European and American brands will change their nose pads for the Asian market. Eyeglasses without a nose pad rely on the bridge of the nose to support the center beam. It's hard for Asians to stand up, and their eyes are more protruding than sunken like westerners. Glasses are usually demanded to keep a 12mm distance between the lens and the eyeball, otherwise, the optical performance will have a great impact.
Operation and Requirements of Drop Ball Test
The ball, which is 0.625 inches in diameter and weighs 0.56 ounces (16 grams), falls from 50 inches (127 centimeters) and hits the center of the lens. The geometrical center of the lens should be struck by the ball within a circle 5/8 inches in diameter. If the lens does not break, it is called a safety lens. There can't be anything that restricts the ball from falling. It cracks across the entire thickness, containing laminated layers (if any), and divides into two or more separate sections across the entire diameter.
