Whether "Neutral optical glass" inorganic material or organic material of optical lenses, in everyday use, due to friction with the dust or grit can cause wear lenses, the lens surface scratches. "Neutral optical glass" Compared to glass, rigid degree of organic materials is relatively low, more susceptible to scratches. Through the microscope, we can observe scratch the lens surface is divided into two types, one is generated due to scratches gravel, shallow and small, wearing glasses is not easy to detect; "Neutral optical glass" and the other is from the larger scratch gravel produced deep and surrounding rough, in the central region will affect vision.
Source:
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