Being wall thickness decisive manner of the glass material for production mannered null precise press molding of wall thickness decisive manner and production manner

摘要

PROBLEM TO BE SOLVED: To provide a means for determining the thickness of an approximately-formed glass preform for precision press molding without doing trial and error.;SOLUTION: A method for determining the thickness of a glass raw material for precision press molding includes the steps of: subjecting a test glass raw material, which includes the same glass material as that of a glass molding to be obtained by precision press molding, has the same volume as that of the glass molding and is thicker than the glass molding, to test press molding so that the obtained molding has the same thickness as that of the glass molding to be obtained; drawing an approximate straight line showing a correlation between the amount of thickness change and a thickness change rate when the test press molding is performed; drawing at least two approximate straight lines by performing the test press molding under at least two different press loads; and determining the thickness of the glass blank for precision press molding so that the thickness of the glass raw material is made equal to or larger than the value which is obtained by adding the value of the amount of thickness change at an intersection point of drawn approximate straight lines to the thickness of the glass molding to be obtained.;COPYRIGHT: (C)2011,JPO&INPIT