Adjusting parallax barriers

A method comprising:

• determining a first distance between a viewer and a display of a device, wherein the display comprises a first parallax barrier including a predetermined number of parallax barrier clusters that are parallel to one another and spaced apart from one another by a barrier cluster pitch distance, and wherein each of the parallax barrier clusters includes a predetermined number of parallax barrier elements that are parallel to one another and parallel to the parallax barrier clusters and spaced apart from one another by a barrier element pitch distance;
• determining a second distance between a right eye of the viewer and a left eye of the viewer;
• moving the parallax barrier elements in each parallax barrier cluster based on the first distance and the second distance to change the barrier element pitch distance between adjacent pairs of parallax barrier elements in the respective parallax barrier cluster, the changing of the barrier element pitch distance inversely changing the barrier cluster pitch distance between adjacent pairs of parallax barrier clusters by the change to the barrier element pitch distance times the number of parallax barrier elements in the parallax barrier cluster minus one parallax barrier element, and wherein the changes in barrier element pitch distance and barrier cluster pitch distance are variable and not limited to a predetermined incremental amount or multiple thereof;
• and
• emitting, from the display and through spaces between the parallax barrier clusters, light rays of a right-eye image of a stereoscopic image and a left-eye image of the stereoscopic image to the right eye of the viewer and the left eye of the viewer, respectively.

A non-transitory computer-readable medium comprising instructions for causing one or more processors executing the instructions to:

• determine a first distance between a viewer and a display of a device based on an output of an auto-focusing component, wherein the display comprises a first parallax barrier including a predetermined number of parallax barrier clusters that are parallel to one another and spaced apart from one another by a barrier cluster pitch distance, and wherein each of the parallax barrier clusters includes a predetermined number of parallax barrier elements that are parallel to one another and parallel to the parallax barrier clusters and spaced apart from one another by a barrier element pitch distance;
• capture an image of a face of the viewer;
• detect an image of a right eye of the viewer and an image of a left eye of the viewer in the image of the face of the viewer;
• determine a second distance between the right eye of the viewer and the left eye of the viewer based on the image of the right eye and the image of the left eye;
• move the parallax barrier elements in each parallax barrier cluster based on the first distance and the second distance to change the barrier element pitch distance between adjacent pairs of parallax barrier elements in the respective parallax barrier cluster, the changing of the barrier element pitch distance inversely changing the barrier cluster pitch distance between adjacent pairs of parallax barrier clusters by the change to the barrier element pitch distance times the number of parallax barrier elements in the parallax barrier cluster minus one parallax barrier element, and wherein the changes in barrier element pitch distance and barrier cluster pitch distance are variable and not limited to a predetermined incremental amount or multiple thereof;
• and
• emit, from the display and through the spaces between the parallax barrier clusters, light rays of a right-eye image of a stereoscopic image and a left-eye image of the stereoscopic image to the right eye of the viewer and the left eye of the viewer, respectively.