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:
May. 12, 2020
Filed:
May. 17, 2019
Alps Alpine Co., Ltd., Ota-ku, Tokyo, JP;
Yoshifumi Masumoto, Niigata-ken, JP;
Kiyoshi Kobayashi, Niigata-ken, JP;
Masayoshi Takeuchi, Niigata-ken, JP;
Alps Alpine Co., Ltd., Tokyo, JP;
Abstract
A multilayer structure includes a touch sensor and an optical functional layer formed thereon. The optical functional layer includes a phase-difference layer and a linear polarization layer formed thereon on a side opposite to the touch sensor. The phase-difference layer which gives a phase difference to transmitted light has a laminated structure including a 1/4λ phase-difference layer and a 1/2λ phase-difference layer. The multilayer structure has first and second retardations at wavelengths of 450 nm and 590 nm, respectively, while the optical functional layer has third and fourth retardations at wavelengths of 450 nm and 590 nm, respectively. A first ratio of the first retardation to the second retardation is smaller than 0.763 and greater than a second ratio of the third retardation to the fourth retardation. A slow axis of the base member extends in a direction parallel to a synthesized slow axis of the optical functional layer.