Ohara, a leading company of optical glass production in Japan announced the sale of Clear Glass Ceramics which has far greater shock resistance than chemically tempered glasses and hardness than sapphire crystal glass. In general, glass ceramics have larger crystal particles which cause low transmittance and are not usable for optical applications. Ohara’s nanotechnology (approx… particle diameter: 6nm) developed for space and astronomy field achieved high-transmittance, and the clear glass ceramics has been qualified to be used as the protector of an interchangeable lens for an SLR camera manufactured by Sigma.
Comparing to general borosilicate glasses, clear glass ceramics hardness is improved by 30%, shock resistance shows more than ten times by falling steel ball impact test; moreover, its hardness is improved by 20%, shock resistance shows more than three times by falling steel ball impact test compared to chemically tempered glasses. In addition, its fracture toughness is superior to sapphire crystal glasses.
Thus, cracks which could cause fractures does not occur even it scratched, and property of material tenaciousness and break-proof is developed. Clear glass ceramics does not break even when max 10 times weighted steel ball is dropped from 1.27 meter height. Ohara expects that the glass will be used for panel covers for mobile devices, in-vehicle electric components, medical devices, etc.
