"Neutral optical glass" having a high transparency, and high uniformity of Chemical Physics (Structure and properties) on, having a specific and precise optical constants. It can be divided silicates, borates, phosphates, fluorides and sulfur compound series. "Neutral optical glass" variety, mainly according to their remaining in the refractive index of the various types of glass as flint (F) glass. General as convex, concave lens made of flint glass. With the "Neutral optical glass" of applications continue to expand, the species is increasing, its composition, including almost all of the elements in the periodic table.
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