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:
Jan. 23, 2007
Filed:
Mar. 28, 2003
Shinya Sannohe, Neyagawa, JP;
Shinya Sannohe, Neyagawa, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
On a transparent substrate (), a first alternating periodic layer () including low-refractive-index layers () and high-refractive-index layers (), a second alternating periodic layer () including the low-refractive-index layers () or the high-refractive-index layers () and intermediate-refractive-index layers (), and a third alternating periodic layer () including the low-refractive-index layers () and the high-refractive-index layers () are provided in this order. The refractive index of the intermediate-refractive-index layers () is higher than that of the low-refractive-index layers () and lower than that of the high-refractive-index layers (). Furthermore, the intermediate-refractive-index layers () contain materials for the low-refractive-index layers () and the high-refractive-index layers (). A dichroic mirror thus configured has a narrow color separating band between a transmission wavelength band and a reflection wavelength band, and therefore has a satisfactory color separating efficiency. Accordingly, a projection-type display unit using the dichroic mirror provides satisfactory color reproduction while retaining a high spectrum utilization efficiency.