It doesn't work, don't be fooled.
Myopia is a type of refractive error. When the eye is in a relaxed state of regulation, parallel light rays enter the eye, its focus before the retina, which leads to the retina can not form a clear image, called myopia (myopia). This results in an inability to form a clear image on the retina, which is called myopia. This is indicated by a myopia test, for example, it is usually called 50 diopters of myopia, and is recorded as "-0.50D".
When the eye is relaxed, parallel light from the outside enters the eye and its focus falls on the retina, a clear image is formed, which is called orthopia; if the focus fails to fall on the retina, it is called anisometropia, or refractive error.
Axial myopia and refractive myopia
Axial myopia: The most common type of myopia, axial myopia is characterized by a long anterior-posterior diameter of the eye (i.e., the axial length of the eye is out of the normal range) and a refractive power (i.e., refractive power of other refractive components of the eye, such as the cornea and lens) that is essentially within the normal range.
Refractive myopia: the refractive power is out of the normal range mainly due to the excessive curvature of the cornea or lens, or the abnormal combination between the refractive components, while the eye axis length is basically in the normal range.
The above content participates in: Baidu Encyclopedia - Myopia