We claim the ornamental design for a head mounted display, as shown and described.
FIG. 1 is a front perspective view of a head mounted display of the present invention;
FIG. 2 is a rear perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a rear view thereof;
FIG. 5 is a first side view thereof;
FIG. 6 is a second side view thereof;
FIG. 7 is a top view thereof;
FIG. 8 is a bottom view thereof; and,
FIG. 9 is a rear perspective view thereof with the slide adjusting arm moved.
The broken line showing of head mounted display is included for the purpose of illustrating environment and forms no part of the claimed design. Additionally, the unevenly broken lines in the drawings define the limits of the claimed design.