Electronic device and method for displaying augmented reality
An electronic device for displaying AR includes: an optical engine; a first polarizer; a polarization converter configured to maintain or convert a polarization direction of light of a real scene; a waveguide from which light of a virtual image is output and through which the light of the real scene is transmitted; a focus tunable lens; a second polarizer; and one or more processors. The one or more processors are configured to, during a first period, control the polarization converter to convert a polarization direction of a first light of the real scene such that at least part of the first light of the real scene is blocked by the second polarizer, and during a second period, control the polarization converter to maintain a polarization direction of a second light of the real scene such that the second light of the real scene is transmitted through the second polarizer.
1. An electronic device for displaying augmented reality, the electronic device comprising:
an optical engine configured to output light of a virtual image;
a first polarizer positioned in a path of light of a real scene;
a polarization converter configured to maintain or convert a polarization direction of the light of the real scene;
a waveguide from which the light of the virtual image is output and through which the light of the real scene is transmitted;
a focus tunable lens configured to adjust a focal length for the light of the virtual image output from the waveguide;
a second polarizer positioned between the waveguide and the focus tunable lens or between the polarization converter and the waveguide; and
one or more processors configured to:
during a first period, control the polarization converter to convert a polarization direction of a first light of the real scene that has passed through the first polarizer such that at least part of the first light of the real scene is blocked by the second polarizer, and
during a second period, control the polarization converter to maintain a polarization direction of a second light of the real scene that has passed through the first polarizer such that the second light of the real scene is passed through the second polarizer.
2. The electronic device of claim 1 , wherein the polarization converter comprises a liquid crystal panel.
3. The electronic device of claim 1 , wherein the one or more processors are further configured to, during the first period, control the optical engine to output the light of the virtual image, and during the second period, control the optical engine not to output the light of the virtual image.
4. The electronic device of claim 1 , wherein the one or more processors are further configured to, during the first period, control the focus tunable lens to have a first focal length for the light of the virtual image, and during the second period, control the focus tunable lens to have a second focal length different from the first focal length.
5. The electronic device of claim 4 , wherein the first focal length is for moving an image plane of the virtual image to a position of a depth of the virtual image.
6. The electronic device of claim 4 , wherein the second focal length is infinite.
7. The electronic device of claim 4 , wherein the second focal length is for correcting a user's vision.
8. The electronic device of claim 1 , wherein the first period and the second period alternate.
9. The electronic device of claim 1 , wherein the one or more processors are further configured to, during the first period, control the optical engine to output light of a plurality of virtual image layers having different depths, respectively, through time division, and control the focus tunable lens according to different first focal lengths corresponding to the different depths of the plurality of virtual image layers.
10. The electronic device of claim 1 , further comprising an eye tracker configured to track a gaze of a user.
11. The electronic device of claim 10 , wherein the one or more processors are further configured to, during the first period, generate the virtual image so that the virtual image has a depth of a gaze point of the user whose gaze is tracked by the eye tracker.
12. The electronic device of claim 10 , wherein the one or more processors are further configured to, during the first period, generate a plurality of virtual image layers having different depths, respectively, and
wherein a frequency of a first virtual image layer having a depth closer to a gaze point of the user whose gaze is tracked by the eye tracker is greater than a frequency of a second virtual image layer having a depth farther from the gaze point of the user, among the plurality of virtual image layers.
13. The electronic device of claim 1 , wherein the focus tunable lens comprises one of a liquid crystal lens, a liquid lens, or a movable lens.
14. The electronic device of claim 1 , wherein the electronic device comprises a glasses-type device.
15. An electronic device for displaying augmented reality, the electronic device comprising:
a waveguide from which light of a virtual image is output and through which light of a real scene is transmitted;
an optical engine positioned at a portion of a rear surface of the waveguide;
an optical shutter positioned at a front surface of the waveguide and configured to transmit or block the light of the real scene;
a focus tunable lens positioned at another portion of the rear surface of the waveguide; and
one or more processors configured to:
during a first period, control the optical shutter to block at least part of a first light of the real scene, and control the focus tunable lens to have a first focal length, and
during a second period, control the optical shutter to transmit a second light of the real scene, and control the focus tunable lens to have a second focal length different from the first focal length.
16. The electronic device of claim 15 , wherein the optical shutter comprises one of a liquid crystal optical shutter or an electrochromic optical shutter.
17. An electronic device for displaying augmented reality, the electronic device comprising:
a waveguide;
an optical engine positioned at a portion of a rear surface of the waveguide;
a polarization converter positioned at a front surface of the waveguide and configured to maintain or convert a polarization direction of light;
a first polarizer positioned at a front surface of the polarization converter;
a focus tunable lens positioned at another portion of the rear surface of the waveguide;
a second polarizer positioned between the waveguide and the focus tunable lens or between the polarization converter and the waveguide; and
one or more processors configured to:
during a first period, control the polarization converter to convert a polarization direction of a first light of a real scene that has passed through the first polarizer such that at least part of the first light of the real scene is blocked by the second polarizer, and
during a second period, control the polarization converter to maintain a polarization direction of a second light of the real scene that has passed through the first polarizer such that the second light of the real scene is passed through the second polarizer.