Patent ID: 9709834
Date: 2017-07-18
CPC Classifications: G02B,G02F,H04N

Claim:
1. An image display apparatus comprising: an image display panel having a first surface and a second surface opposing to the first surface, and configured to display an image; a light device located on a first surface side of the image display panel, and configured to emit light to the first surface of the image display panel; a first variable deflection element located between the image display panel and the light device, including first triangular prisms which have ridge lines extending in a first direction, the first triangular prisms being arranged along a second direction perpendicular to the first direction, the first variable deflection element being configured to variably change a deflection direction of the light along the second direction as the light passes through the first variable deflection element, the first direction being parallel to a single straight line; a second variable deflection element distinct from the first variable deflection element, located between the image display panel and the first variable deflection element, including second triangular prisms which have ridge lines extending in the first direction, the second triangular prisms being arranged along the second direction, the second variable deflection element being configured to variably change a deflection direction of the light along the second direction as the light passes through the second variable deflection element, the ridge lines of the first triangular prisms extend parallel to the ridge lines of the second triangular prisms; and a position detector configured to detect a user position of a user, who is watching the image on the image display panel, in the second direction, wherein, when the user position detected by the position detector moves along the second direction, at least one of the first variable deflection element and the second variable deflection element changes the deflection direction along the second direction, and each of the first triangular prisms has a first triangular cross section having a first line, a second line, and a third line, the first line being longer than the second line and longer than the third line, each of the second triangular prisms has a second triangular cross section having a first line, a second line, and a third line, the first line being longer than the second line and longer than the third line, and a plane defined by the first line of the first triangular cross section and a plane defined by the first line of the second triangular cross section intersect with one another.