How should children correctly match glasses? Experts point out that to measure the level of glasses matching in an eyeglass shop, it depends on whether the indicators meet the national standards, and whether the indicators can be determined and implemented in a targeted, more reasonable and personalized way according to the wearer's wearing habits and actual situation Big one. The reporter interviewed two ophthalmologists about the problems that students should pay attention to in summer.
The size of the frame should not be too large
When teenagers wear glasses, it is better to choose plastic frames and pure titanium frames with light materials, and the size of the frames should not be too large. In consideration of the width of the face, the closer the frame size to the actual pupil distance of the eyes, the better. The director of the optometry Department of Nanning optometry and matching center said, "this can avoid excessive inward displacement of lens optical center due to the large size of the lens frame, thus causing the prism effect of wearing discomfort. '
Resin lens is the best choice
The choice of lens is very important. "It's best for teenagers to choose light weight, non fragile resin lenses. If engaged in sports, it is best to choose PC lens with excellent impact resistance (polycarbonate). "The director said," it's good for teenagers who are in the developing stage. Nowadays, there are many kinds of resin lenses. You can choose the most suitable lens according to the diopter of your eyes. '
Experts pointed out that generally speaking, if the diopter is within 3.00ds, low refractive index lenses (1.49, 1.499, 1.5, 1.502) can be selected; if the diopter is between 3.00ds and 5.00ds, medium refractive index lenses (1.56, 1.57) can be selected. Then, high refractive index lenses (1.6, 1.61, 1.67, 1.71 and 1.74) can be selected if the diopter is within 3.00ds. Especially the choice of high refractive index lens, it can not only greatly reduce the thickness of the lens than the same refractive index lens of low refractive index, but also lighter weight. In addition, it is better to add antireflective coating to all the above refractive index lenses. Because the coated lens can improve the clarity of the object of vision, so as to reduce the fatigue of eyesight. Of course, the choice of lens depends on the affordability.
With regard to lenses, the director specially reminds everyone to pay attention to the surface quality and internal defects of lenses. Due to the low level of processing, many lenses often have a variety of surface quality problems. The most common are poor surface finish, spiral, Huoguang (light jump), orange peel, pockmarks, scratches, stripes, chipping, etc. These surface quality problems usually lead to distortion of vision, blurring, vertigo, nausea and even cardiac discomfort in patients with ametropia. The damage to human eyes caused by poor surface quality of lens is no less than other indexes. The surface quality of lens should be included in the scope of daily inspection. The so-called surface quality problems do not mean that we can find them intuitively with the naked eye. Therefore, it is particularly important to select glasses shops with reputation, service, equipment and technology.