Display system for rendering a scene with multiple focal planes

A method of displaying a scene using a display device, comprising:

• varying a light field projected from a display element according to a sequence of different image frames;
• directing, with an optical element, the light field from the display element into a field of view of the display device;
• and
• varying a focal length of the optical element through a series of different focal lengths while measuring the focal length of the optical element and varying the light field, based on the measuring, to display the scene by presenting each of the image frames at a plurality of the focal lengths;
• wherein, during measuring of the focal length, a control signal is configured to cause the optical element to continuously adjust the focal length to sweep across a range between a minimum focal length and a maximum focal length.

A method of displaying a scene comprising a series of image frames at different positions in a depth of field of the scene using a display device, comprising:

• determining a display frame rate for displaying the image frames with a display element;
• determining a set of focal planes for displaying a corresponding image frame of the scene;
• generating a first control signal configured to cause an optical element to cycle through a range of focal lengths at a frequency lower than the display frame rate;
• measuring a focal length of the optical element as the optical element cycles through the range of focal lengths;
• and
• generating, based on the measurement, a second control signal configured to cause the display element to display the corresponding image frame when a focal length of the optical element corresponds to a plurality of focal planes of the set of focal planes, the image frame corresponding to the plurality of focal planes for the depth of field of the scene;
• wherein, during measuring of the focal length, the first control signal is configured to cause the optical element to continuously adjust the focal length to sweep across a range between a minimum focal length and a maximum focal length.