Head mounted display having alignment maintained via structural frame

1. A head mounted display device comprising:

a structural frame arranged generally along a first axis and a second axis for viewing along a third axis, the first, second, and third axes being mutually perpendicular, the structural frame including opposing upper and lower rims between which are defined left and right openings;

left and right micro-displays coupled to the structural frame, and configured to project visual content in a substantially forward direction along the third axis toward the left and right openings, respectively, and away from a user;

left and right optical elements coupled to the structural frame and respectively positioned over the left and right openings and each including an at least partially reflective surface facing in a substantially rearward direction along the third axis; and

wherein the structural frame maintains the optical elements in alignment to define an optical light path for reflectively guiding a light ray bundle from the micro-displays to a user's eyes,

wherein the structural frame includes left and right pockets each extending downward from the upper rim along the second axis toward the lower rim and respectively containing the left and right micro-displays,

wherein each of the optical elements includes a first mirror and a third mirror with reflective optical surfaces facing in a substantially rearward direction along the third axis and further comprising left and right second mirrors coupled to the structural frame with reflective optical surfaces facing in a substantially forward direction along the third axis.

2. The head mounted display device of claim 1 , wherein the reflective optical surface of each of the first and third mirrors is a concave reflective optical surface.

3. The head mounted display device of claim 2 , wherein the reflective optical surface of each of the second mirrors is a convex reflective optical surface.

4. The head mounted display device of claim 1 , wherein the optical light path is forward from the micro-displays to the first mirrors, rearward and downward from the first mirrors to the second mirrors, forward and downward from the second mirrors to the third mirrors, and rearward and downward from the third mirrors to the user's eyes.

5. A head mounted display device comprising:

a structural frame arranged generally along a first axis and a second axis for viewing along a third axis, the first, second, and third axes being mutually perpendicular, the structural frame including opposing upper and lower rims between which are defined left and right openings;

left and right micro-displays coupled to the structural frame, and configured to project visual content in a substantially forward direction along the third axis toward the left and right openings, respectively, and away from a user;

left and right optical elements coupled to the structural frame and respectively positioned over the left and right openings and each including an at least partially reflective surface facing in a substantially rearward direction along the third axis; and

wherein the structural frame maintains the optical elements in alignment to define an optical light path for reflectively guiding a light ray bundle from the micro-displays to a user's eyes,

wherein the structural frame includes left and right pockets each extending downward from the upper rim along the second axis toward the lower rim and respectively containing the left and right micro-displays.

6. The head mounted display device of claim 5 , wherein the first axis is a substantially horizontal axis and the second axis is a substantially vertical axis, and wherein the micro-displays are spaced apart along the first axis, and extend downward from the upper rim along the second axis toward the lower rim.

7. The head mounted display device of claim 5 , wherein each of the left and right pockets extends downward less than half of a distance from the upper rim toward the lower rim.

8. The head mounted display device of claim 7 , wherein the left and right second mirrors are respectively mounted on the left and right pockets below the left and right micro-displays along the second axis.

9. The head mounted display device of claim 5 , wherein the left and right micro-displays are respectively implemented in left and right micro-display mechanisms that include mechanisms for user adjustment of focus and interpupillary distance.

10. The head mounted display device of claim 1 , wherein the structural frame is formed from an alloy having a specific gravity of less than 2.

11. The head mounted display device of claim 1 , wherein the structural frame is made of an injection molded or cast magnesium alloy.

12. A head mounted display device comprising:

a structural frame arranged generally along a first axis and a second axis for viewing along a third axis, the first, second, and third axes being mutually perpendicular, the structural frame including opposing upper and lower rims between which are defined left and right openings;

left and right micro-displays coupled to the structural frame, and configured to project visual content in a substantially forward direction along the third axis toward the left and right openings, respectively, and away from a user;

left and right optical elements coupled to the structural frame and respectively positioned over the left and right openings and each including an at least partially reflective surface facing in a substantially rearward direction along the third axis; and

wherein the structural frame includes left and right pockets each extending downward from the upper rim along the second axis toward the lower rim and respectively containing the left and right micro-displays,

wherein the structural frame maintains the optical elements in alignment to define an optical light path for reflectively guiding a light ray bundle from the micro-displays to a user's eyes, wherein the structural frame is made of cast magnesium alloy, wherein the magnesium alloy comprises a composition containing primarily magnesium.

13. The head mounted display device of claim 1 wherein each of the optical elements includes a first optical element defining the first mirror and a second optical element defining the third mirror.

14. The head mounted display device of claim 1 wherein each of the optical elements is a compound optical element incorporating the first and third mirrors into one optical element.

15. The head mounted display device of claim 1 wherein the structural frame provides datums for receiving the optical elements and facilitating assembly.

16. A method of assembling optical components to a structural frame for a head-mounted display, the method comprising:

providing a structural frame including opposing upper and lower rims between which are defined left and right openings;

inserting left and right micro-displays into respective left and right pockets formed in the upper rim;

attaching left and right second mirrors to respective left and right mounts formed on the left and right pockets, respectively;

attaching left and right optical elements to the structural frame on a front side of the micro-displays, wherein the left and right optical elements respectively cover at least a portion of the left and right openings; and

wherein the structural frame maintains the optical elements and the second mirrors in alignment to define an optical light path for reflectively guiding a light ray bundle from the micro-displays to a user's eyes.

17. The method of claim 16 , wherein each of the left and right optical elements includes a first mirror and a third mirror.

18. The method of claim 17 , wherein the optical light path is forward from the micro-displays to the first mirrors, rearward and downward from the first mirrors to the second mirrors, forward and downward from the second mirrors to the third mirrors, and rearward and downward from the third mirrors to the user's eyes.

19. The method of claim 16 , wherein the structural frame is arranged generally along a first axis and a second axis for viewing along a third axis, the first, second, and third axes being mutually perpendicular, and wherein the left and right micro-displays are configured to project visual content in a substantially forward direction along the third axis toward the left and right openings, respectively, and away from the user's eyes.

20. The method of claim 16 , and further comprising:

incorporating the left and right micro-displays into respective left and right micro-display mechanisms that include mechanisms for user adjustment of focus and interpupillary distance; and

wherein the inserting of the left and right micro-displays into respective left and right pockets formed in the upper rim comprises inserting the left and right micro-display mechanisms with the respective left and right micro-displays incorporated therein into the left and right pockets, respectively.

21. A head mounted display device, comprising:

a structural frame arranged generally along a first axis and a second axis for viewing along a third axis, the first, second, and third axes being mutually perpendicular, the structural frame including opposing upper and lower rims between which are defined first and second openings;

first and second micro-display mechanisms maintained in respective first and second pockets formed in the upper rim, and configured to project visual content in a substantially forward direction along the third axis toward the first and second openings, respectively, and away from a user;

first and second optical elements coupled to the structural frame on a front side of the micro-display mechanisms and respectively covering at least a portion of the first and second openings, wherein each of the first and second optical elements includes at least one reflective optical surface facing in a substantially rearward direction along the third axis;

at least one second mirror coupled to the structural frame and having a reflective optical surface facing in a substantially forward direction along the third axis; and

wherein the structural frame maintains the optical elements and the at least one second mirror in alignment to define an optical light path for reflectively guiding a light ray bundle from the micro-display mechanisms to a user's eyes.

22. The head mounted display device of claim 21 , wherein the each of the first and second optical elements comprises a compound optical element with a first mirror and a third mirror with reflective optical surfaces facing in a substantially rearward direction along the third axis.