what is the average pd for a child?

Choose a quality progressive lens.

Superior progressive lenses provide a better viewing experience. They also remove any distortions you might feel when reading what's in front of you. Lenses can also be coated with special coatings. Anti-reflective coating can prevent glare on the road, and anti-scratch coating can reduce wear marks.

ATTCL Retro Polarized Night Driving Glasses

These glasses have metal frames. The metal frame uses an aluminum-magnesium alloy structure, strong and light. While you'll see them available in a variety of colors, you'll still have to choose the night vision option if you want to buy night driving glasses. The anti-glare yellow night lens is designed to filter 20 percent of glare at night.

What Do the Numbers on Glasses Mean?

In this section, we will show you the glasses numbers meaning. These numbers on glasses frames are the measurements that indicate and describe the size of your eyeglasses frames, specifically:

1. The eye size number (it is the size of the lenses on your frame).
2. The bridge size number (the distance between the lenses).
3. The temple length number (it is the size of that part of your eyeglasses frame, which rests upon your ears).

The three numbers mentioned above are the key measurements that describe the glasses measurements of the frames in eyeglasses. For example, you will see three numbers like 51-17-145 at the temple of your glasses. These numbers help the optician to choose the best-fitted frame for your head size and facial features.

All of these three numbers are measured in millimeters. These variations in frame numbers are fitted by a skilled optician so that it should be best fitted, be comfortable and look good on the appearance.

Look at the quality of the frame.

Put the glasses flat in front of your eyes, and see if the color of the temples is different in-depth or light under the same light intensity. Sometimes, due to the mistakes in processing, the color asymmetry of the left and right temples will appear.Technology is the quality assurance of the frame, and a frame of fine technology is often reflected in the details.Pay more attention to the welding point near the metal frame to see if there are cracks.

The thermal effect during welding changes the stress structure of the material, or the weld defect, material fatigue, and so on will make it easy to fracture.Attention should be paid to see if the two sides of the stipules of the lens frame are symmetrical and if the fixation is safe.

Armani glasses

As a sub-brand of luxury Armani, it is a high-end eyewear brand. It is representative of exquisite quality and noble luxury, and it pays attention to details and displays noble temperament. The handmade frame, superb craft, and workmanship make the charm of the Armani spectacle frame show in front of everyone. The medical environment-friendly silicone nose pad is designed according to the structure of the human nose bridge, which not only fits the nose more but is very comfortable. The prices of the Armani frame are basically around 1500 yuan.

Aspheric lenses are different from spherical lenses.

Spherical lenses: The higher the strength of spherical lenses, the worse the visual experience, because the spherical lenses do not eliminate aberrations. Aspheric lens: it can greatly reduce the deformation of things and make people see more clearly and vividly. Besides, the eyes are not easy to get tired and the appearance is beautiful. It reduces the aberration of the lens and ensures a clearer field of vision.

When the parameters of the lens are normal, the optical center of the myopic lens is the clearest, and the peripheral part of the lens will be slightly deformed. So now the lens is designed with an aspheric surface. Under normal circumstances, the mainstream aspheric lens in the market has a reduced edge design, which is about 5 to degrees lower. The opposite edge of a spherical lens is higher.

Common Problems with Varifocal Glasses

In this section, we will list some common problems with varifocal glasses. The most common problem with varifocal glasses is people being unable to focus on what they need to. Losing focus often leads to some discomforts such as headaches or dizziness when performing tasks that require quick changes in near and middle-distance focus.

Besides, some people also experience a sort of swimming feeling when they are walking. It may be caused by being very aware of the distortions in your peripheral vision as well as the reading portion at the lower part of the lenses.

So, how to use varifocal glasses? The best way is to keep yourself from looking downward as you walk. You may also experience soft focus at the edges of the lenses and need to move your head more to see near objects better.