Rolling burst illumination for a display

• US 10,643,528 B2
• Filed: 01/23/2018
• Issued: 05/05/2020
• Est. Priority Date: 01/23/2018
• Status: Active Grant

• Current Assignee: Valve Corporation
• Original Assignee: Valve Corporation
• Inventors: Selan, Jeremy Adam
• Primary Examiner(s): Cerullo, Liliana
• Application Number:
  US15/878,163
• Publication Number:
  US 20190228700A1
• Time in Patent Office: 833 Days
• CPC Class Codes: G09G 2310/0237 Switching ON and OFF the backlight within one frame
• CPC Class Codes: G09G 2310/024 Scrolling of light from the illumination source over the display in combination with the scanning of the display screen
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 2320/064 by time modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2320/0653 Controlling or limiting the speed of brightness adjustment of the illumination source
• CPC Class Codes: G09G 3/3208 organic, e.g. using organic light-emitting diodes [OLED]
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers

Abstract

A display has an array of light emitting elements. For a given frame of a series of frames that present images on the display at a refresh rate of the display, the light emitting elements may be driven by loading individual subsets of the light emitting elements in sequence with light output data, and by illuminating the individual subsets of the light emitting elements in the sequence and in accordance with the light output data, wherein an illumination time period is within a range of about 2% to 80% of a frame time of the frame, the frame time derivable from the refresh rate. This “rolling burst illumination” technique is characterized by the relatively short illumination time period (e.g., as compared to the frame time), and it can stabilize a scene (or mitigate unwanted visual artifacts) for a viewing user during head motion, as well as optimize display bandwidth utilization.

Claims

1. A display comprising:

an array of light emitting elements arranged on a substrate that is parallel to a frontal plane of the display in rows and columns, wherein the rows of the light emitting elements include respective sets of rows comprising a first set of odd-numbered rows and a second set of even-numbered rows;

display driver circuitry coupled to the array of light emitting elements via conductive paths, the display driver circuitry including;

first display driver circuitry coupled to the odd-numbered rows of the light emitting elements via the conductive paths; and

second display driver circuitry coupled to the even-numbered rows of the light emitting elements via the conductive paths; and

one or more controllers to;

for a frame of a series of frames that present images on the display, cause performance of loading and illuminating operations for the respective sets of rows by;

causing the first display driver circuitry to load the odd-numbered rows of the light emitting elements sequentially with first light output data at a first rate;

causing the second display driver circuitry to load the even-numbered rows of the light emitting elements sequentially with second light output data at the first rate;

causing the first display driver circuitry to illuminate the odd-numbered rows of the light emitting elements sequentially and in accordance with the first light output data at a second rate that is faster than the first rate; and

causing the second display driver circuitry to illuminate the even-numbered rows of the light emitting elements sequentially and in accordance with the second light output data at the second rate;

wherein the loading and illuminating operations of the respective sets of rows overlap in time;

wherein each row of light emitting elements is illuminated once, not multiple times, per frame.

2. The display of claim 1, wherein the one or more controllers are further configured to wait a predefined time period since loading a first row of the light emitting elements with the first light output data before causing the first display driver circuitry to illuminate the first row of the light emitting elements.

3. The display of claim 1, wherein:

the one or more controllers are further configured to;

cause the first display driver circuitry and the second display driver circuitry to load the light emitting elements over a loading time period measured from a time of loading a first row of the light emitting elements with the first light output data to a time of loading a last row of the light emitting elements with at least one of the first light output data or the second light output data; and

cause the first display driver circuitry and the second display driver circuitry to illuminate the light emitting elements over an illumination time period measured from a time of illuminating the first row of the light emitting elements to a time of illuminating the last row of the light emitting elements; and

the illumination time period is less than the loading time period.

4. The display of claim 1, wherein the display is a liquid crystal display (LCD), the array of the light emitting elements represents a backlight of the LCD, and the light emitting elements are light emitting diodes (LEDs).

5. The display of claim 1, wherein the display is an organic light emitting diode (OLED) display, the individual light emitting elements in the array of the light emitting elements are light emitting diodes (LEDs) included in individual pixels of the OLED display.

6. The display of claim 1, wherein the display is embedded in a virtual reality (VR) headset or an augmented reality (AR) headset.

7. The display of claim 1, wherein the first display driver circuitry and the second display driver circuitry are configured to load and illuminate the array of light emitting elements from opposite sides of the substrate.

8. The display of claim 1, wherein:

causing the first display driver circuitry to illuminate the odd-numbered rows of the light emitting elements sequentially comprises illuminating multiple odd-numbered rows at a time in sequence; and

causing the second display driver circuitry to illuminate the even-numbered rows of the light emitting elements sequentially comprises illuminating multiple even-numbered rows at a time in sequence.

9. A method implemented by a display having an array of light emitting elements arranged on a substrate that is parallel to a frontal plane of the display in rows and columns, wherein the rows of the light emitting elements include respective sets of rows comprising a first set of odd-numbered rows and a second set of even-numbered rows, the method comprising:

for a frame of a series of frames that present images on the display, performing loading and illuminating operations for the respective sets of rows by;

loading the odd-numbered rows of the light emitting elements sequentially with first light output data at a first rate;

loading the even-numbered rows of the light emitting elements sequentially with second light output data at the first rate;

illuminating the odd-numbered rows of the light emitting elements sequentially in accordance with the first light output data at a second rate that is faster than the first rate; and

illuminating the even-numbered rows of the light emitting elements sequentially in accordance with the second light output data at the second rate;

wherein the loading and illuminating operations of the respective sets of rows overlap in time;

wherein each row of light emitting elements is illuminated once, not multiple times, per frame.

10. The method of claim 9, further comprising waiting a predefined time period since loading a first row of the light emitting elements with the first light output data before illuminating the first row of the light emitting elements.

11. The method of claim 9, wherein:

the loading of the odd-numbered rows and the loading of the even-numbered rows is performed over a loading time period measured from a time of loading a first row of the light emitting elements with the first light output data to a time of loading a last row of the light emitting elements with at least one of the first light output data or the second light output data;

the illuminating of the odd-numbered rows and the illuminating of the even-numbered rows is performed over an illumination time period measured from a time of illuminating the first row of the light emitting elements to a time of illuminating the last row of the light emitting elements; and

the illumination time period is less than the loading time period.

12. The method of claim 9, wherein:

the illuminating of the odd-numbered rows and the illuminating of the even-numbered rows is performed over an illumination time period measured from a time of illuminating a first row of the light emitting elements to a time of illuminating a last row of the light emitting elements; and

the illumination time period of the frame is no greater than about ⅓

of a frame time of the frame.

13. The method of claim 9, wherein:

the illuminating of the odd-numbered rows and the illuminating of the even-numbered rows is performed over an illumination time period measured from a time of illuminating a first row of the light emitting elements to a time of illuminating a last row of the light emitting elements;

a refresh rate of the display is at least about 75 hertz (Hz); and

the illumination time period of the frame is no greater than about 3 milliseconds (ms).

14. The method of claim 9, wherein:

first display driver circuitry performs the loading and the illuminating of the odd-numbered rows of the light emitting elements from a first side of the substrate; and

second display driver circuitry performs the loading and the illuminating of the even-numbered rows of the light emitting elements from a second side of the substrate opposite the first side.

15. A display comprising:

an array of light sources arranged on a substrate that is parallel to a frontal plane of the display in rows and columns, wherein the rows of the light sources include respective sets of rows comprising a first set of odd-numbered rows and a second set of even-numbered rows;

display driver circuitry coupled to the array of light sources via conductive paths, the display driver circuitry including;

first display driver circuitry coupled to the odd-numbered rows of the light sources via the conductive paths; and

second display driver circuitry coupled to the even-numbered rows of the light sources via the conductive paths; and

one or more controllers to;

for a frame of a series of frames that present images on the display, cause performance of loading and illuminating operations for the respective sets of rows by;

causing the first display driver circuitry to load the odd-numbered rows of the light sources sequentially with first light output data at a first rate;

causing the second display driver circuitry to load the even-numbered rows of the light sources sequentially with second light output data at the first rate;

causing the first display driver circuitry to illuminate the odd-numbered rows of the light sources sequentially and in accordance with the first light output data at a second rate that is faster than the first rate; and

causing the second display driver circuitry to illuminate the even-numbered rows of the light sources sequentially and in accordance with the second light output data at the second rate,

wherein the loading and illuminating operations of the respective sets of rows overlap in time;

wherein each row of light sources is illuminated once, not multiple times, per frame.

16. The display of claim 15, wherein:

the series of frames present the images on the display at a refresh rate of the display;

the first display driver circuitry and the second display driver circuitry illuminate the light sources over an illumination time period measured from a time of illuminating a first row of the light sources to a time of illuminating a last row of the light sources; and

the illumination time period of the frame is within a range of about 2% to 80% of a frame time of the frame, the frame time derivable from the refresh rate.

17. The display of claim 15, wherein:

the conductive paths are arranged in horizontal lines and vertical lines on the substrate; and

the display driver circuitry is configured address an individual light source of the light sources via a pair of a horizontal line and a vertical line that intersects at the individual light source for loading light output data that is particular to the individual light source.

18. The display of claim 15, wherein the first display driver circuitry and the second display driver circuitry are configured to load and illuminate the array of light sources from opposite sides of the substrate.

19. The display of claim 15, wherein:

causing the first display driver circuitry to illuminate the odd-numbered rows of the light sources sequentially comprises illuminating multiple odd-numbered rows at a time in sequence; and

causing the second display driver circuitry to illuminate the even-numbered rows of the light sources sequentially comprises illuminating multiple even-numbered rows at a time in sequence.