... glass,Pyrex,borosilicat glass 2.Semi ball lens 3.Plano,Round,Ball 4.Polished Lens 5.Clear and optical quality Pyrex glass ... ,borosilicate glass2. Techniques of semi ball lens: by Molding, Grinding, Polishing3. Shape of semi ball lens: Plano convex,semi ball,ball4. Inside ... of semi ball lens: clear and transparent, no mold marks, no inside bubble and dirts,5. Function of semi ball lens: Lighting and ...