Three-dimensional display apparatus with a wide viewing angle and increased resolution

A three-dimensional display apparatus comprising at least one image display device, the image display device including a display device and an optical device,

• wherein the display device includes a plurality of pixel groups, each including a plurality of display pixels arranged in a first direction,
• the optical device includes a plurality of sampling portions transmitting light, arranged in the first direction and in a second direction orthogonal to the first direction, each being optically coupled with each of the plurality of pixel groups, and
• the sampling portions adjacent each other in the second direction are disposed at different positions in the first direction,
• wherein each of the plurality of sampling portions is a slit which is long in a second direction perpendicular to the first direction, and a length of the slit is shorter than a length of each of the plurality of pixel groups along the second direction.