Important to measure pupils
The interpupillary distance refers to the distance between the centers of the two pupils when the visual axis is square and parallel. In general, the optical center of the glasses should coincide with the visual axis of the eye when looking at eye level. That is, the optical center distance of the glasses should be the same as the interpupillary distance. Otherwise, visual discomfort will occur, causing visual fatigue and deepening the degree. Therefore, we must improve consumers' awareness of self-quality protection. Understand the knowledge of glasses, otherwise, only mild myopia, the long-term wearing of unqualified glasses will cause the degree to deepen and become high myopia. So be sure to go to a regular optician to get glasses.
Tungsten carbon glasses frame
Tungsten carbon material, one of the obvious advantages of this material is that it has good toughness and is ultra-lightweight. People will feel no pressure when wearing such glasses. It is good if you are a sportsperson who chooses it.
Choose clear glasses with the right materials for kids.
A critical point for children to choose frames is to think about the weight, to avoid wearing for a long time, or they will be uncomfortable, unstable, easy to slip. It is recommended to choose an ultra-light plate or TR90 lens frame, which has good chemical properties, good thermal stability, with no deformation, good recovery, and no side effects, lightweight, and convenient material.
Titanium alloys have low thermal elasticity
The thermal conductivity of titanium is about 1/4 of nickel, 1/5 of iron, 1/14 of aluminum, and the thermal conductivity of different titanium alloys is about 50% lower than that of titanium.
The elastic modulus of titanium alloy is about 1/2 that of steel, so its rigidity is poor and is easy to deform, and it is not suitable to make slender rods and thin wall parts. When cutting, the spring back of the processing surface is very large, about 2 ~ 3 times of stainless steel, resulting in severe friction, adhesion, and bonding wear of the knife surface.
Can you adjust your glasses by yourself?
If your frames are not suitable, adjusting your glasses at home may be easier than you think. You can solve the most common problems in the frame by yourself, but sometimes taking your glasses to an optician is the best thing to do. Of course, if your problem is your lenses, that's something you can't usually fix at home.
Plate glasses frame
Sheet glasses frames are generally made of high-tech plastic memory sheets. Its appearance is beautiful and fashionable, and its styles are diverse. Therefore, plank glasses are easier to match with clothes, which can show the personality and style of the wearer.
What is a progressive lens?
Progressive multifocal lenses are lenses with different upper and lower powers for seeing far above and below for seeing near. The distance from the fixed far power above the lens to the near power fixed below the lens does not change suddenly, but a gradual transition between the two through the gradual change in refractive power. Compared with ordinary lenses, there are many advantages. The appearance of the lens is like a single vision lens, and the dividing line of the power change is not visible. Not only is the appearance beautiful, but more importantly, it protects the age privacy of the wearer, and there is no need to worry about revealing the age secret due to wearing glasses.
Since the change of the lens power is gradual, there will be no image jump. It is comfortable to wear and easy to adapt. So it is easy to be accepted. Because the degree is gradual, the replacement of the adjustment effect is gradually increased according to the shortening of the short distance. There is no adjustment fluctuation, and it is not easy to cause visual fatigue. Clear vision can be obtained at all distances in the visual range.
Such a pair of glasses meets the use of long-distance, near-use and various distances in the middle at the same time. It is especially good news for teachers, doctors, music workers, and computer operators, because these people not only need to see far and near objects clearly, but most of the time they also need to be able to see middle distance objects such as blackboards, piano scores, and computer screens. . This is not possible with any lens other than progressive lenses.