Vector scanning augment reality
A method of displaying images by vector scanning in a head-mounted display includes determining, based on content of an image to be displayed by the head-mounted display, a vector scanning pattern for displaying the image, the vector scanning pattern including a plurality of scan lines and one or more transition lines connecting the plurality of scan lines, at least one transition line of the one or more transition lines including a curved section (or loop); generating control signals for controlling a scanner to steer, according to the vector scanning pattern, a light beam emitted by a light source towards a waveguide display of the head-mounted display; and generating modulation signals for modulating the light source such that the light beam is turned on when the scanner operates according to the plurality of scan lines and is turned off when the scanner operates according to the one or more transition lines.
1. A head-mounted display system comprising:
a light source configured to emit a light beam;
a scanner configured to steer the light beam;
a waveguide display configured to receive the light beam from the scanner and direct the light beam towards an eyebox of the head-mounted display system;
one or more processors electrically coupled to the light source and the scanner; and
one or more memory devices storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations including:
determining, based on content of an image, a vector scanning pattern for displaying the image, wherein the vector scanning pattern includes a plurality of scan lines and one or more transition lines connecting the plurality of scan lines, and wherein at least one transition line of the one or more transition lines includes a curved section;
generating control signals for controlling the scanner to steer the light beam according to the vector scanning pattern; and
generating modulation signals for modulating the light source such that the light beam is turned on when the scanner operates according to the plurality of scan lines and is turned off when the scanner operates according to the one or more transition lines.
2. The head-mounted display system of claim 1 , wherein the one or more transition lines include a transition line that forms a loop to connect two scan lines of the plurality of scan lines.
3. The head-mounted display system of claim 1 , wherein controlling the scanner to steer the light beam according to the vector scanning pattern comprises controlling the scanner to:
steer the light beam at a first velocity when the scanner operates according to a scan line of the plurality of scan lines; and
steer at a second velocity that is higher than the first velocity when the scanner operates according to a transition line of the one or more transition lines.
4. The head-mounted display system of claim 1 , wherein controlling the scanner to steer the light beam according to the vector scanning pattern comprises controlling the scanner to steer the light beam at a variable velocity based on brightness information of the image when the scanner operates according to a scan line of the plurality of scan lines.
5. The head-mounted display system of claim 1 , further comprising dynamic blur optics configured to dynamically change a beam width of the light beam emitted by the light source.
6. The head-mounted display system of claim 5 , wherein the instructions further cause the one or more processors to control the dynamic blur optics based on the content of the image to dynamically change the beam width of the light beam emitted by the light source.
7. The head-mounted display system of claim 1 , wherein:
the one or more memory devices further store brightness nonuniformity information of the waveguide display; and
the instructions further cause the one or more processors to compensate brightness nonuniformity of the waveguide display by performing at least one of:
generating, based on the brightness nonuniformity information of the waveguide display, control signals for varying a scanning velocity of the scanner; or
generating, based on the brightness nonuniformity information of the waveguide display, modulation signals for modulating an output power of the light source.
8. The head-mounted display system of claim 1 , wherein the scanner includes a micro-mirror and an actuator for rotating the micro-mirror.
9. The head-mounted display system of claim 1 , wherein the light source includes at least one of a laser that can be modulated or an optical modulator configured to modulate the light beam.
10. The head-mounted display system of claim 1 , wherein the waveguide display includes:
a substrate transparent to visible light;
an input coupler configured to couple the light beam into the substrate such that the light beam is guided by the substrate; and
an output coupler configured to couple the light beam out of the substrate at one or more locations of the substrate.
11. The head-mounted display system of claim 1 , further comprising an eye-tracking system.
12. The head-mounted display system of claim 11 , wherein the instructions further cause the one or more processors to determine the content of the image based on outputs of the eye-tracking system.
13. A processor-implemented method comprising:
determining, based on content of an image to be displayed by a head-mounted display system, a vector scanning pattern for displaying the image, wherein the vector scanning pattern includes a plurality of scan lines and one or more transition lines connecting the plurality of scan lines, and wherein at least one transition line of the one or more transition lines includes a curved section;
generating control signals for controlling a scanner to steer, according to the vector scanning pattern, a light beam emitted by a light source towards a waveguide display of the head-mounted display system; and
generating modulation signals for modulating the light source such that the light beam is turned on when the scanner operates according to the plurality of scan lines and is turned off when the scanner operates according to the one or more transition lines.
14. The processor-implemented method of claim 13 , wherein the one or more transition lines include a transition line that forms a loop to connect two scan lines of the plurality of scan lines.
15. The processor-implemented method of claim 13 , wherein controlling the scanner to steer the light beam according to the vector scanning pattern comprises controlling the scanner to:
steer the light beam at a first velocity when the scanner operates according to a scan line of the plurality of scan lines; and
steer at a second velocity that is higher than the first velocity when the scanner operates according to a transition line of the one or more transition lines.
16. The processor-implemented method of claim 13 , wherein controlling the scanner to steer the light beam according to the vector scanning pattern comprises controlling the scanner to steer the light beam at a variable velocity based on brightness information of the image when the scanner operates according to a scan line of the plurality of scan lines.
17. The processor-implemented method of claim 13 , further comprising generating, based on the content of the image, control signals for controlling dynamic blur optics to dynamically change a beam width of the light beam.
18. The processor-implemented method of claim 13 , further comprising:
obtaining brightness nonuniformity information of the waveguide display;
compensating brightness nonuniformity of the waveguide display by performing at least one of:
generating, based on the brightness nonuniformity information of the waveguide display, control signals for varying a scanning velocity of the scanner; or
generating, based on the brightness nonuniformity information of the waveguide display, modulation signals for modulating an output power of the light source.
19. The processor-implemented method of claim 13 , wherein the vector scanning pattern includes a region that includes a raster scanning pattern.
20. The processor-implemented method of claim 13 , wherein determining, based on the content of the image to be displayed by the head-mounted display system, the vector scanning pattern for displaying the image comprises:
detecting edges of features in the image; and
determining the vector scanning pattern based on the detected edges of the features in the image.