Patent ID: 11966071
Assignee: SHARP DISPLAY TECHNOLOGY CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC G | IPC F

Claim 0:
1. An illumination device comprising:
a first sheet including a first light entering main surface being one main surface disposed along a first direction, a first light emission main surface being another main surface along the first direction, a plurality of first light blocking portions being disposed side by side at an interval in the first direction, and a plurality of first light-transmitting portions being disposed side by side at an interval in the first direction, the plurality of first light blocking portions and the plurality of first light-transmitting portions being repeatedly and alternately disposed side by side in the first direction;
a second sheet including a second light entering main surface being one main surface disposed along the first direction and configured to face the first light emission main surface, a second light emission main surface being another main surface along the first direction, and a first lens disposed on the second light entering main surface or the second light emission main surface; and
a third sheet including a third light entering main surface being one main surface disposed along the first direction and configured to face the second light emission main surface, a third light emission main surface being another main surface along the first direction, a plurality of second light blocking portions being disposed side by side at an interval in the first direction, and a plurality of second light-transmitting portions being disposed side by side at an interval in the first direction, the plurality of second light blocking portions and the plurality of second light-transmitting portions being repeatedly and alternately disposed side by side in the first direction,
wherein the first lens includes a first inclined surface having an inclination rising from an end side in the first direction in the second sheet toward a central side, and
the third sheet has a ratio acquired by dividing a width of the plurality of second light-transmitting portions by a height of the plurality of second light-transmitting portions greater than a ratio acquired by dividing a width of the plurality of first light-transmitting portions by a height of the plurality of first light-transmitting portions.