Reflective headset with cropped collector mirror
A device in which one or more reflective collector elements receive image data from one or more light-emitting visual sources to be transmitted to an eyebox, which together form elements of a head mounted display (“HMD”) useful for augmented reality (“AR”) or virtual reality (“VR”) applications, and where the one or more reflective collector elements are cropped to receive a portion of the image data from the one or more light-emitting visual sources, such that the etendue product at the one or more reflective collector elements is about the same as the etendue product within the eyebox.
1 . A head mounted display device comprising:
a wearable, head mounted frame; and
at least one near-to-eye optics housing connected to said frame and configured to be positioned at least partially in front of an eye of a user, said optics housing comprising:
a light-emitting visual source for projecting visual content,
a plurality of reflective optical surfaces in optical communication with said light-emitting visual source, and
an optical path defined by said plurality of reflective optical surfaces, said optical path extending from said light-emitting visual source to an eyebox of said optical path,
wherein said plurality of reflective optical surfaces are configured to reflect light rays from a projection of said visual content between each one of said reflective optical surfaces in a predefined sequential order along said optical path and into said eyebox, and
wherein said reflective optical surfaces are configured to cooperatively magnify said projection of said visual content, such that said projected visual content appears magnified when viewed at said eyebox;
wherein the first of said plurality of reflective optical surfaces in said predefined sequential order has a width smaller than that needed to capture all light emitted by the light-emitting visual source;
wherein said first of said plurality of reflective optical surfaces with said width discards light emitted by the light-emitting visual source such that the etendue product at the first of said plurality of reflective optical surfaces is about the same as the etendue product at said eyebox.
2 . The head mounted display device of claim 1 , wherein the first of said plurality of reflective optical surfaces has a width between about 10 mm and about 50 mm.
3 . The head mounted display device of claim 2 , wherein the first of said plurality of reflective optical surfaces is positioned at a distance between about 10 mm and about 70 mm away from the light-emitting visual source.
4 . The head mounted display device of claim 3 , wherein the light-emitting visual source has an aperture between about 3 mm and about 15 mm.
5 . The head mounted display device of claim 4 , wherein the eyebox has an aperture between about 3 mm and about 15 mm.
6 . The head mounted display device of claim 5 , wherein the first of said plurality of reflective optical surfaces is cropped such that between about 30 and about 80 percent of the light emitted by the light-emitting visual source is discarded.
7 . The head mounted display device of claim 5 , wherein the first of said plurality of reflective optical surfaces in said predefined sequential order has a length smaller than that needed to capture all light emitted by the light-emitting visual source.
8 . The head mounted display device of claim 7 , wherein the first of said plurality of reflective optical surfaces has a length between about 10 mm and about 50 mm.
9 . The head mounted display device of claim 1 , wherein the first of said plurality of reflective optical surfaces is cropped such that between about 30 and about 80 percent of the light emitted by the light-emitting visual source is discarded.