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summer vacation is coming up soon. Winter and summer vacations every year, all students are receiving laser surgery for short-sightedness of a peak period. A clinical survey showed that more than 90% of high school students to remove the glasses is based on the purpose of the college entrance examination in the future when the need to apply some kind of professional, college students are more due to job-seekers. To this end, they are often the best hope that the degree of myopia for the return of zero. Experts have pointed out that the laser treatment of myopia, zero is not necessarily Read more »

1. Balls lens. Balls lens is nearly parallel to the axis of the beam at a point of convergence of the lens, the location of the axis of refraction equal to the force. Convex lens () for the correction of presbyopia and hyperopia, in law and in the mirror and negative spherical lens; concave lens (a) used to correct short-sightedness and in law and in spherical surface lens and now.
2. Lens column: column so that the lens axis nearly parallel to the beam on the convergence of the two. The separation, orthogonal each other's online coke, sub-convex lens column () column with the concave Read more »

anisometropia
inevitable merger of the other refractive errors, with the exception of refractive errors of Merger have clinical, following Anisometropia some of the performance, such as the single obstacle to the eyes; the turn of vision; amblyopia (monocular vision); strabismus. So
anisometropia rely mainly on optical correction, and optical should pay attention to the following:
(1) mild anisometropia very common phenomenon is that most people can wear to adapt to, without feeling unwell, and some early Dai from time to time visual symptoms of fatigue, after a few weeks can be used Read more »

black eye is a common problem it seems people are not tired, a lot of people want to be happy unless, in the end there will be Weishi Yao black eye it? How black eye to prevention, treatment do?
Luoang France in 1992 under the doctor's report, causing the black eye of the reasons include the following:
(a) of the genetic congenital or acquired eyelid increased pigmentation;
(b) to relax the aging eyes, skin wrinkles caused by the appearance together To deepen color;
(c) appear on behalf of the eyes caused by the shadow;
(d) of the eyes with tears formed under the Depressi Read more »

WHO in 1977 put forward the meaning of low vision: diagnosis of visual impairment, but still has residual vision can be used, and the best corrected visual acuity greater than 0.05, less than 0.3
Figure 1-01WHO1973 blind and low vision to develop standards to improve the low vision
One way or compensation for helping with distribution, as the device. Its mechanism of action of the following three aspects: First, adjust the focus and clarity of the image, that is, by common vision glasses would be best to Correction Second, adjusting the size of the image, that is, the line And to enlarg Read more »