Near-eye display device with relay optical prism and optical combiner

A near-eye display device, comprising:

• an image generating device disposed to provide an image light;
• an optical prism element disposed on a transmission path of the image light from the image generating device, wherein the optical prism element is a relay optical element disposed to guide the image light, the optical prism element comprises a first refractive surface, a first reflective surface, a second reflective surface, a plane mirror and a second refractive surface that guide the image light in sequence, each of the surfaces is eccentrically positioned relative to the others and form an interior filled with a medium having a refractive index greater than 1;
• and
• a partial reflective optical element disposed on a transmission path of the image light from the optical prism element, wherein the partial reflective optical element is an optical combiner disposed to guide the image light and an external ambient light toward an exit pupil,
• wherein the image generating device comprises a display element having a display plane, and a chief ray of the image light satisfies the following conditions:
• (1) the chief ray passes through the first refractive surface along a projection optical axis, and the projection optical axis is perpendicular to the display plane;
• (2) the chief ray is in a converging state after passing through the first refractive surface;
• and (3) the chief ray is in a crossed state relative to the projection optical axis either between the first reflective surface and the second reflective surface, or between the second reflective surface and the second refractive surface,
• wherein the near-eye display device satisfies a condition as follows:
• 3.2<(L1+L2)/R<4.3, where L1 is a distance from a surface reference point of the first refractive surface to a surface reference point of the first reflective surface, L2 is a distance from the surface reference point of the first reflective surface to a surface reference point of the second reflective surface, and R is a radius of curvature of the first refractive surface.