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In China, lens products have undergone four revolutions from their birth to the present. Before the 1930s, the main material in the field of optics was optical glass. However, most of the optical glass had a high proportion and was easy to be broken, which brought a lot of inconvenience to wearers. In response to the shortcomings of the glass lens, the researchers struggled to find alternatives, and finally invented a resin lens. Compared with optical glass, optical resin lens has the advantages of light weight, impact resistance and easy to be processed into shape, etc. Once launched, it quickly replaced optical glass as the mainstream product of ophthalmic lens. The first revolution in lenses was epoch-making, as consumers said goodbye to bulky, fragile and unsafe glass lenses.