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:
Sep. 10, 2013
Filed:
Aug. 05, 2009
Akira Sakai, Osaka, JP;
Kazuyoshi Sakuragi, Osaka, JP;
Akira Sakai, Osaka, JP;
Kazuyoshi Sakuragi, Osaka, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
The present invention provides at low cost a display device with superior visibility and high contrast ratio even in a bright room environment through a reduction in the undesired reflection, not only of the incident outside light from the normal direction, but also of the outside incident light from an oblique direction. The present invention is a circularly polarizing plate including a polarizer and a λ/4 plate, and the aforementioned circularly polarizing plate includes an anti-reflective layer, the aforementioned polarizer, a birefringent layer, and the aforementioned λ/4 plate which are laminated in this order, the NZ coefficient of the aforementioned birefringent layer satisfies NZ<0.1, the in-plane fast axis of the aforementioned birefringent layer is orthogonal to the absorption axis of the aforementioned polarizer, the NZ coefficient of the aforementioned λ/4 plate satisfies NZ>0.9, and the in-plane slow axis of the aforementioned λ/4 plate intersects the absorption axis of the aforementioned polarizer.