Patent ID: 11934069
Assignee: SHARP DISPLAY TECHNOLOGY CORPORATION
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A liquid crystal display device, comprising:
a polarizing louver that functions as an optical louver including, sequentially from a viewing surface side toward a back surface side:
a viewing-surface-side polarizer;
a retarder; and
a back-surface-side polarizer;

a liquid crystal panel directly on a viewing surface side of the viewing-surface-side polarizer of the polarizing louver; and
a polarizer directly on a viewing surface side of the liquid crystal panel; wherein
the back-surface-side polarizer is a reflective polarizer,
a transmission axis of the viewing-surface-side polarizer and a transmission axis of the back-surface-side polarizer are parallel to each other,
the polarizing louver has an average angle θ between an angle θ1 and an angle θ2 of not smaller than 50° and not greater than 80°,
the angle θ1 is equal to the angle θ2,
the angle θ1 represents an angle formed by an optical axis of the retarder on a first surface adjacent to the back surface with the first surface adjacent to the back surface; and the angle θ2 represents an angle formed by an optical axis of the retarder on a second surface adjacent to the viewing surface with the second surface adjacent to the viewing surface,
the optical axis of the retarder on the first surface adjacent to the back surface and the optical axis of the retarder on the second surface adjacent to the viewing surface each have an azimuth of 90°±3°, provided that an azimuth of 0° is set to the horizontally right direction on a screen of the liquid crystal panel and that the azimuths measure positive in a counterclockwise direction and measure negative in a clockwise direction,
each of the optical axes of the retarder on the first surface and on the second surface is inclined from normal directions of the first surface and the second surface, and
each of the azimuths of the optical axes is defined as an azimuth of a direction from a side closer to the first surface to a side closer to the second surface along the optical axis.