NEODIUM GLASS FOR ENVELOPE AND FILTER OF TUNGSTEN-HALOGEN LAMP

• Main Author: STEWART RONALD LEROY
• Format: Patent
• Language: English; Korean
• Published: 25.08.2001
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMICAL COMPOSITION OF GLASSES, GLAZES, OR VITREOUSENAMELS; CHEMISTRY; ELECTRIC INCANDESCENT LAMPS; ELECTRICITY; GLASS; JOINING GLASS TO GLASS OR OTHER MATERIALS; METALLURGY; MINERAL OR SLAG WOOL; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS,MINERALS OR SLAGS; SURFACE TREATMENT OF GLASS

PURPOSE: A glass composition for the envelope, glass filter lens, and glass filter of a tungsten-halogen lamp, and an envelope and filter produced by using the composition are provided, to obtain the tungsten-halogen lamp having a physical properties required for a high-temperature lamp operation and to increase a correlation color temperature (CCT) to 3,200 deg.C. CONSTITUTION: The glass composition comprises 50-62 wt% of SiO2, 10-17 wt% of Al2O3, 0-6 wt% of B2O3, 3.6-10 w% of CaO, 0-7.5 wt% of MgO, 0.1-0.3 wt% of SrO, 2.4-18 wt% of BaO, 0-1 wt% of ZnO, and 1-8 w% of Nd2O3. The glass composition has a deformation point of 665-750 deg.C; a coefficient of thermal expansion of 49-59x10¬-7 per deg at a set point of 25 deg.C to a temperature above the deformation point by 5 deg.C or more; a liquid temperature below 12320 deg.C; a viscosity of 2,000 or more; and a transmittance of 5-60 % at 585 nm to a glass with a thickness of 1.2 mm.