Display device

1. A display device, comprising:

a display unit that includes a display surface emitting video light for displaying a composite image of a first image and a second image different from the first image;

a separation unit that separates the video light into first video light representing the first image and second video light representing the second image;

a detection unit that detects a position of an observer looking at the composite image; and

an image control unit that controls a direction of the composite image in accordance with the position of the observer detected by the detection unit, wherein

the detection unit detects a position of the eyes of the observer,

the image control unit specifies an observation direction in which a direction extending from the position of the eyes of the observer, which is detected by the detection unit, toward the display surface is projected onto a plane including the display surface,

causes the display unit, in a case where an angle between the specified observation direction and a reference direction, which is a direction perpendicular to a reference side of the display surface, is zero degrees, to display the composite image at a position where a base of the composite image matches the reference side, and, in a case where the angle between the observation direction and the reference direction is within a first range of zero degrees ±20 degrees excluding zero degrees, a second range of 90 degrees ±20 degrees, a third range of 180 degrees ±20 degrees, or a fourth range of 270 degrees ±20 degrees, to display the composite image at a position where the base of the composite image is rotated by an angle between the observation direction and the reference direction from the reference side, and

causes the display unit to display only one of the first image or second image at a position where the base of the one of the first image or second image is rotated by an angle between the observation direction and the reference direction from the reference side in a case where the angle between the observation direction and the reference direction is outside the first range, the second range, the third range, and the fourth range, and

the separation unit has a barrier pattern that is configured by a slit portion for transmitting the video light from the display unit and a shielding portion for shielding the video light, the display device further comprising:

a barrier pattern control unit that transmits the entire video light from the display unit without forming the barrier pattern on an entire surface of the separation unit in the case where the angle between the observation direction and the reference direction is outside the first range, the second range, the third range, and the fourth range.

2. The display device according to claim 1 , wherein

the composite image includes a first image region and a second image region that is displayed between the first image region and the observer when the observer is present at a first position, and

in the case where the presence of the observer at a second position different from the first position is detected by the detection unit, the image control unit controls the direction of the composite image in such a manner that the second image region is displayed between the first image region and the observer present at the second position.

3. The display device according to claim 1 , wherein

the first image is a left image observed by the left eye,

the second image is a right image observed by the right eye, and

the separation unit separates the video light in such a manner as to input left video light representing the left image into the left eye and right video light representing the right image into the right eye.

4. The display device according to claim 1 , wherein

the detection unit detects positions of a plurality of observers, and

the image control unit divides the display surface into a plurality of display regions in accordance with the number of the plurality of observers, and controls the direction of the composite image in each of the plurality of display regions in accordance with the positions of the plurality of observers that are detected by the detection unit.

5. The display device according to claim 1 , wherein

the barrier pattern control unit changes the barrier pattern in accordance with a direction of the composite image that changes in response to a change in the angle between the observation direction and the reference direction in the case where the angle between the observation direction and the reference direction is within the first range, the second range, the third range, or the fourth range.

6. The display device according to claim 1 , wherein

the detection unit detects a position of the eyes of the observer, and

the image control unit specifies a direction extending from the position of the eyes of the observer, which is detected by the detection unit, toward the display surface, and controls a display position of the composite image in accordance with information on the position of the eyes of the observer in the specified direction and information on a position of the separation unit.