| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method by which the glass optical element can be formed in a comparatively short cycle time even at the time of greatly deforming a glass material in order to form a glass optical element and also a glass optical element having excellent quality with respect to profile irregularity cap be formed. SOLUTION: This manufacturing method comprises forming a heated and softened glass material to be formed into a glass formed body by pressing the glass material with a forming mold which consists of a male mold and a female mold and is preheated to such a temp. that the center thickness of the resulting glass formed body is <=70% of the center thickness of the glass material. At this time, the preheating temp. of the forming mold is set to such a temp. that the average of temp. in the vicinity of the forming surface of each of the male and female molds becomes equal to a temp. at which the glass material shows an X viscosity value (poise) and also, the heating temp. of the glass material is set to a temp. at which the glass material shows a Y viscosity value (poise), wherein the X viscosity value and the Y viscosity value are selected so as to concurrently satisfy the following relational expressions: logX<10; logY>=6.5; Y<X; and -logX+14.5<=logY<=-logX+18.</p> |
