US 8,079,713 B2 · Near eye display system

Abstract

A near eye image display system includes an image projector, a beam combiner assembly, and an optical assembly, optically coupled between the image projector and the beam combiner assembly. The image projector projects a display image toward an optical pathway, the optical pathway intersecting a viewing axis, the viewing axis extending from the eye of a user to an ambient scene. The beam combiner assembly includes a plurality of beam combiners optically cascaded along the optical pathway, each of the beam combiners being disposed diagonally to the optical pathway and diagonally to the viewing axis. Each of the beam combiners is arranged such that for each two adjacent beam combiners, the first of the adjacent beam combiners is optically located between the second of the adjacent beam combiners and the image projector. The geometrical projection of the second beam combiner onto a first plane perpendicular to the optical pathway, is subsumed within the geometrical projection of the first beam combiner onto the first plane. Each of the beam combiners is further arranged such that the partial geometric projection of each of the beam combiners onto a second plane perpendicular to the viewing axis forms a continuous geometric projection, the optical assembly directing display light of the display image from the image projector toward the beam combiner assembly along the optical pathway. Each of the beam combiners reflects the display light toward the eye, and further directs ambient light emerging from the ambient scene toward the eye, thereby superimposing the display image onto the ambient scene.

Near eye image display system comprising:

an image projector, projecting a display image toward an optical pathway, said optical pathway intersecting a viewing axis, said viewing axis extending from the eye of a user to an ambient scene;
a beam combiner assembly comprising a plurality of beam combiners, said beam combiners optically cascaded along said optical pathway, each of said beam combiners being disposed diagonally to said optical pathway and diagonally to said viewing axis;
each of said beam combiners arranged such that for each two adjacent said beam combiners, the first of said adjacent beam combiners being optically located between the second of said adjacent beam combiners and said image projector, the geometrical projection of said second beam combiner onto a first plane being perpendicular to said optical pathway, is subsumed within the geometrical projection of said first beam combiner onto said first plane,
each of said beam combiners further arranged such that the partial geometric projection of each of said beam combiners onto a second plane being perpendicular to said viewing axis, forms a continuous geometric projection;
and
an optical assembly, optically coupled between said image projector and said beam combiner assembly, said optical assembly directing display light of said display image from said image projector toward said beam combiner assembly along said optical pathway;
and
a double prism assembly optically coupled between said image projector and said optical assembly, said double prism assembly including a first prism and a second prism, each said first prism and said second prism having at least a first surface, a second surface and a third surface, wherein said first surface, said second surface and said third surface are geometrically extendable to form a triangle, each said first prism and said second prism being made of transparent material,
wherein said first surface of said first prism is coupled to said image projector, said first prism receiving said display light from said image projector, at a substantially perpendicular direction to said first surface of said first prism,
wherein said first surface of said second prism is coupled to said optical assembly, said second prism directing said display light toward said optical assembly, at a substantially perpendicular direction to said first surface of said second prism,
wherein for each of said first prism and said second prism, the angle between said third surface and said first surface is substantially 67°30′
(
3
⁢
⁢
π
8
)
,
the angle between said third surface and said second surface is substantially 67°30′
(
3
⁢
⁢
π
8
)
,
and the angle between said first surface and said second surface substantially 45°
(
π
4
)
,
wherein said second surface of said first prism is disposed adjacent to said second surface of said second prism, with a transparent medium there between, wherein the ratio between the refractive index of said transparent material and the refractive index of said transparent medium is such that said ratio produces total internal reflection of a first light beam, incident on said second surface of said first prism, said first light beam arriving at said second surface of said first prism at a substantially perpendicular direction to said first surface of said first prism, said ratio further producing total internal reflection of a second light beam incident on said second surface of said second prism, said second light beam exiting said second surface of said second prism at a substantially perpendicular direction to said first surface of said second prism,
wherein for each of said first prism and said second prism, said third surface is optically reflective, providing total internal reflection,
wherein said double prism assembly directs said display light toward said optical assembly along said optical pathway, and
wherein each of said beam combiners reflects said display light toward said eye, and wherein each of said beam combiners further directs ambient light emerging from said ambient scene toward said eye, thereby superimposing said display image onto said ambient scene.

35 more elements

Near eye display system

Life of this patent

Near eye display system

Life of this patent

Abstract

Claims49