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Optical Glasses    
 
Optical Glasses
Optical Glasses
Optical glass is mixed with oxides of high-purity silicon, boron, sodium, potassium, zinc, lead, magnesium, calcium, barium etc, in accordance with specific formula, melted in high temperature in platinum crucible, stirred evenly with ultrasonic wave, and removed bubbles; then cooled slowly for a long time to avoid internal stress of glass block.

The cooled glass blocks must be measured by optical instruments to check the purity, transparency, uniformity, refractive index and dispersion index. 
The qualified glass block is heated and forged to form optical glasses.

 
     
 
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