... No air bubble 5) resist high temperature Pyrex glass1) Materila : Borosilicate glass 3.3,Borofloat ... 3.3,Pyrex 3.3 2) Techniques for Pyrex : by Molding or Cutting, Grinding, ... Polishing3) Quality of Pyrex : Resistance to hight temperature shock,High ... dirts,4) Application of Pyrex: Light System,Electronics 5) Purpose of Pyrex:Including square lens,film lens ...