Ultraviolet ray transmission filter

• Main Authors: KAWAI, YOHEI, SAKAGAMI, TAKAHIRO, NAKAYAMA, KAZUHIKO
• Format: Patent
• Language: Chinese; English
• Published: 16.07.2018
• Subjects: APPARATUS SPECIALLY ADAPTED THEREFOR; CHEMICAL COMPOSITION OF GLASSES, GLAZES, OR VITREOUSENAMELS; CHEMISTRY; CINEMATOGRAPHY; ELECTROGRAPHY; GLASS; HOLOGRAPHY; JOINING GLASS TO GLASS OR OTHER MATERIALS; MATERIALS THEREFOR; METALLURGY; MINERAL OR SLAG WOOL; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; ORIGINALS THEREFOR; PHOTOGRAPHY; PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES,e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTORDEVICES; PHYSICS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS,MINERALS OR SLAGS; SURFACE TREATMENT OF GLASS

Provided is an ultraviolet ray transmission filter which has a high transmittance of ultraviolet light, in particular, deep ultraviolet light, and in which deterioration of transmittance is suppressed even in the case of long-term use. An ultraviolet ray transmission filter 1 has a glass plate 2 and a protective film 3 disposed on the main surface of the glass plate 2, wherein the glass plate 2 contains 55-80% of SiO2, 12-27% of B2O3, 4-20% of R2O (R represents at least one alkali metal selected from the group consisting of Li, Na, and K), 0-5% of Al2O3, 0-5% of R'O (R' represents at least one alkali earth metal selected from the group consisting of Mg, Ca, Sr, and Ba), 0-5% of ZnO, 0-20% of ZrO2, and 0-5% of Ta2O5 on an oxide-based molar percentage basis, and is formed of a glass having a transmittance of at least 70% for a wavelength of 254 nm, said transmittance being the spectral transmittance at a glass thickness of 0.5 mm.