Wide angle and high resolution tiled head-mounted display device
A tiled head-mounted display device, comprising: an optical component including a plurality of prisms with free-form surfaces, each prism being a wedge prism comprising a first optical surface, a second optical surface and a third optical surface; and a display component including a plurality of micro-displays, wherein the number of the micro-displays and the number of the prisms with free-form surfaces is identical. The tiled head-mounted display device according to the present invention is compact and light, provides wide field of view and high resolution, especially for the optical tiling head-mounted display device, the exit pupil planes of each display channels are coincident, thus avoiding pupil aberration and keeping exit pupil diameter and eye clearance same as the single ocular. There is no resolution variance throughout the entire field of view, thus preventing extra trapezoid distortion. The tiled head-mounted display device according to the present invention can be readily applicable to augmented environments applications by simply adding an auxiliary free-form lens behind the free-form prism.
1. A tiled head-mounted display device, comprising:
an optical component including a plurality of prisms with free-form surfaces, each prism being a wedge-shaped prism, the wedge-shape bounded by a first optical surface, a second optical surface and a third optical surface to provide the wedge-shape,
wherein each prism with free-form surfaces constitutes a display channel, and a global coordinate system is defined as: a global coordinate origin O is at the exit pupil center; Z-axis is in a direction along the viewing axis of a user's eye; Y-axis is perpendicular to Z-axis and extends right above the eye; X-axis is perpendicular to both Y-axis and Z-axis, constituting a Cartesian coordinate system;
wherein the display channels are tiled so that an overall field of view of the tiled device is configured to be a summation of the individual fields of view of each display channel and the center of the exit pupil of each display channel in the tiled device is configured to be located at a pupil center of the user's eye,
wherein the head-mounted display device comprises a first display channel and a second display channel, the first display channel rotated by a first angle in the XOZ plane about the Y-axis of the global coordinate system, the second display channel rotated by the first angle in the opposite direction about the Y-axis of the global coordinate system.
2. The tiled head-mounted display of claim 1 , wherein the head-mounted display device comprises a third display channel and a fourth display channel, the third display channel rotated by the predetermined angle about the Y-axis of the global coordinate system, the fourth display channel rotated by the predetermined angle in the opposite direction about the Y-axis of the global coordinate system.
3. The tiled head-mounted display of claim 2 , wherein the head-mounted display device comprises a fifth display channel and a sixth display channel, the fifth display channel rotated by a second angle about the Y-axis of the global coordinate system, the sixth display channel rotated by the second angle in the opposite direction about the Y-axis of the global coordinate system.
4. The tiled head-mounted display device according to claim 1 , wherein the exit pupil diameter is at least 6 mm.
5. The tiled head-mounted display device according to claim 1 , wherein the eye clearance is at least 15 mm.
6. The tiled head-mounted display device of claim 1 , wherein the first optical surface, the second optical surface and the third optical surface are disposed in a counter-clockwise order relative to the X-axis, and the first optical surface and the second optical surface are free-form surfaces, the third optical surface is selected from a free-form, spherical or non-spherical surface, the first optical surface is a transmissive surface, the second optical surface is a concave reflective surface or semi-transmissive and semi-reflective surface, and the third optical surface is a transmissive surface.
7. The tiled head-mounted display device of claim 1 , wherein the tiled head-mounted display has a horizontal field of view of at least 70° and a vertical field of view of at least 30°.
8. The tiled head-mounted display device of claim 1 , wherein the tiled head-mounted display has a horizontal field of view of at least 100° and a vertical field of view of at least 30°.
9. The tiled head-mounted display device of claim 1 , wherein the tiled head-mounted display has a horizontal field of view of at least 120° and a vertical field of view of at least 30°.
10. The tiled head-mounted display device of claim 1 , wherein the tiled head-mounted display has a horizontal field of view of at least 70° and a vertical field of view of at least 50°.
11. The tiled head-mounted display device of claim 1 , wherein the tiled head-mounted display has a horizontal field of view of at least 100° and a vertical field of view of at least 50°.
12. The tiled head-mounted display device of claim 1 , wherein the tiled head-mounted display has a horizontal field of view of at least 120° and a vertical field of view of at least 50°.