1. Institute of Laser EngineeringOsaka University2‐6 Yamada‐okaSuitaOsaka565‐0871Japan
2. Faculty of Science and EngineeringKinki University3‐4‐1 KowakaeHigashiosaka CityOsaka577‐8502Japan
3. Production Engineering SectionOptical Glass Production DepartmentSumita Optical Glass, Inc.174‐1 Tabehara, TajimaMinamiaizu‐gun967FukushimaJapan
4. Glass Research DivisionR&D DepartmentSumita Optical Glass, Inc.4‐7‐25 Harigaya, Urawa‐kuSaitama City330SaitamaJapan