The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 21, 1987
Filed:
May. 02, 1985
Tetsuo Kyogoku, Toyokawa, JP;
Minolta Camera Kabushiki Kaisha, Osaka, JP;
Abstract
An optical filter comprising a colored glass plate having band-pass filter characteristics and an interference multilayer film formed over the glass plate. The colored glass plate defines a transmission band of relatively narrow width in the visible range. The interference multilayer film comprises at least two unit layers and a low refractive index material layer interposed therebetween and having an optical thickness of .lambda..sub.o /4. The unit layer is composed of two high refractive index material layers having an optical thickness of .lambda..sub.o /4 and a low refractive index material layer interposed therebetween and having an optical thickness of .lambda..sub.o /2. The interference multilayer film is designed to define a reflection band for removing a predetermined range of wavelengths from the transmission band of the color glass plate.