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, wherein each prism with free-form surfaces and the corresponding micro-display constitutes a display channel, a coordinate system is defined as: global coordinate origin O is exit pupil center; Z-axis is in a direction along the viewing axis of 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; wherein the display channels are tiled at either bottom surfaces or side surfaces of the respective prisms with free-form surfaces so that an overall field of view of the tiled device can be substantially a summation of individual field of view of each display channel and the center of exit pupil of each display channel in the tiled device is located at a pupil center of the user's eye, the bottom surface is positioned between the first optical surface and the second optical surface of the respective prism, and the side surface intersects with all of the first optical surface, the second optical surface and the third optical surface of the respective prism, wherein the prism comprises a first optical surface, a second optical surface and a third optical surface in a counter-clockwise order relative to X-axis, and the first optical surface and the second optical surface are free-form surfaces, the third optical surface is selected from 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. 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, wherein each prism with free-form surfaces and the corresponding micro-display constitutes a display channel, a coordinate system is defined as: global coordinate origin O is exit pupil center; Z-axis is in a direction along the viewing axis of 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; wherein the display channels are tiled at either bottom surfaces or side surfaces of the respective prisms with free-form surfaces so that an overall field of view of the tiled device can be substantially a summation of individual field of view of each display channel and the center of exit pupil of each display channel in the tiled device is located at a pupil center of the user's eye, the bottom surface is positioned between the first optical surface and the second optical surface of the respective prism, and the side surface intersects with all of the first optical surface, the second optical surface and the third optical surface of the respective prism, wherein the prism comprises a first optical surface, a second optical surface and a third optical surface in a counter-clockwise order relative to X-axis, and the first optical surface and the second optical surface are free-form surfaces, the third optical surface is selected from 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.