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:
Feb. 25, 2020
Filed:
Apr. 06, 2018
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Kenta Watanabe, Osaka, JP;
Abstract
A wavelength conversion device includes: a substrate; and a phosphor layer on the substrate. The phosphor layer includes: a base material; and a first phosphor and a second phosphor each of which emits fluorescent light when excited by excitation light. Where chromaticity coordinates of the fluorescent light emitted by the first phosphor and chromaticity coordinates of the fluorescent light emitted by the second phosphor are (x1, y1) and (x2, y2), respectively, −0.02≤x1−x2≤0.02 and −0.02≤y1−y2≤0.02 are satisfied. A peak wavelength of an excitation spectrum of the first phosphor is different from a peak wavelength of an excitation spectrum of the second phosphor.