Image display apparatus and head mounted display

A head mounted display comprising:

• (a) a frame shaped like glasses to be worn on the head of an observer;
• and
• (b) an image display apparatus attached to the frame, the image display apparatus including
• an image forming device configured to emit light;
• and an optical device configured to guide and emit the light, wherein a central light beam that is emitted from the center of the image forming device is tilted with respect to a normal axis of the optical device, and
• wherein the central light beam guided and emitted from the optical device is tilted with respect to a horizontal plane.

A head mounted display comprising:

• (a) a frame shaped like glasses to be worn on the head of an observer;
• and
• (b) an image display apparatus attached to the frame, the image display apparatus including
• an image forming device configured to emit light;
• and an optical device configured to guide and emit the light, wherein a central light beam that is emitted from the center of the image forming device is tilted with respect to a normal axis of the optical device, and
• wherein the central light beam is configured to guide in the optical device diagonally.

An image display apparatus comprising:

• an image forming device configured to emit light;
• and an optical device configured to guide and emit the light,
• wherein when a point where a central light beam that is emitted from the center of the image forming device enters the optical device is defined as an optical device center point, an axis that passes through the optical device center point, and is parallel to the axis direction of the optical device is defined as an X-axis, and an axis that passes through the optical device center point, and coincides with the normal axis of the optical device is defined as a Y-axis,
• the central light beam intersects the XY plane at angles other than 0 degree.