Backlight controlling apparatus, backlight controlling method and program

• US 9,653,026 B2
• Filed: 03/04/2013
• Issued: 05/16/2017
• Est. Priority Date: 03/07/2012
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Tatsumi, Eisaku
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): Azongha, Sardis F
• Application Number:
  US13/783,690
• Publication Number:
  US 20130234922A1
• Time in Patent Office: 1,534 Days
• 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 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• 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 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2340/0435 Change or adaptation of the frame rate of the video stream
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336

Abstract

A timing controller performs control to cause a backlight to emit light at first brightness for a first time in a period that original image data is displayed on a liquid crystal panel, and cause the backlight to emit light at second brightness darker than the first brightness for a second time longer than the first time in a period that intermediate image data generated based on the original image data is displayed on the liquid crystal panel.

Claims

1. A backlight controlling apparatus which controls a backlight in a displaying apparatus for displaying image frames based on image data at a display frame rate which is double an input frame rate, comprising:

an input unit configured to input original image data of the input frame rate;

a generating unit configured to generate intermediate image data corresponding to an intermediate image frame based on the original image data;

a determining unit configured to determine a light emission period and a light emission intensity for causing the backlight to emit light in accordance with whether the displaying apparatus displays an original image frame based on the original image data or the intermediate image frame based on the intermediate image data generated by the generating unit based on the original image data such that (i) a first light emission period of the backlight for displaying the original image frame based on the original image data is shorter than a second light emission period of the backlight for displaying the intermediate image frame based on the intermediate image data, (ii) a first light emission intensity of the backlight for displaying the original image frame based on the original image data is higher than a second light emission intensity of the backlight for displaying the intermediate image frame based on the intermediate image data, and (iii) a first integrated value defined based on integrating the first light emission intensity by the first light emission period is approximately equal to a second integrated value defined based on integrating the second light emission intensity by the second light emission period; and

a controlling unit configured to, in a case where the displaying apparatus displays image frames at the display frame rate which is double the input frame rate of the original image data, perform control to cause the backlight to emit light at the first light emission intensity for the first light emission period for displaying the original image frame based on the original image data on the displaying apparatus, and cause the backlight to emit light at the second light emission intensity for the second light emission period for displaying the intermediate image frame based on the intermediate image data generated by the generating unit based on the original image data on the displaying apparatus.

2. The backlight controlling apparatus according to claim 1, wherein the controlling unit controls the backlight in a scanning manner.

3. The backlight controlling apparatus according to claim 1, wherein the controlling unit independently controls each block in the backlight of a direct-beneath type.

4. The backlight controlling apparatus according to claim 1, wherein the controlling unit simultaneously blinks a whole surface of the backlight.

5. The backlight controlling apparatus according to claim 1, wherein the controlling unit performs the control to cause the backlight to intermittently emit light at least either at a time when emitting light at the first light emission intensity or at a time when emitting light at the second light emission intensity.

6. The backlight controlling apparatus according to claim 1, further comprising a display controlling unit configured to display the original image frame based on the original image data and the intermediate image frame based on the intermediate image data so that a gradation of the intermediate image data is lower than a gradation of the original image data,

wherein the controlling unit causes the backlight to emit light in an even light quantity.

7. A backlight controlling method which is performed by a backlight controlling apparatus which controls a backlight in a displaying apparatus for displaying image frames based on image data at a display frame rate which is double an input frame rate, comprising:

inputting original image data of the input frame rate;

generating intermediate image data corresponding to an intermediate image frame based on the original image data;

determining a light emission period and a light emission intensity for causing the backlight to emit light in accordance with whether the displaying apparatus displays an original image frame based on the original image data or the generated intermediate image frame based on the intermediate image data generated based on the original image data such that (i) a first light emission period of the backlight for displaying the original image frame based on the original image data is shorter than a second light emission period of the backlight for displaying the intermediate image frame based on the intermediate image data, (ii) a first light emission intensity of the backlight for displaying the original image frame based on the original image data is higher than a second light emission intensity of the backlight for displaying the intermediate image frame based on the intermediate image data, and (iii) a first integrated value defined based on integrating the first light emission intensity by the first light emission period is approximately equal to a second integrated value defined based on integrating the second light emission intensity by the second light emission period; and

in a case where the displaying apparatus displays image frames at the display frame rate which is double the input frame rate of the original image data, performing control to cause the backlight to emit light at the first light emission intensity for the first light emission period for displaying the original image frame based on the original image data on the displaying apparatus, and cause the backlight to emit light at the second light emission intensity for the second light emission period for displaying the intermediate image frame based on the intermediate image data generated based on the original image data on the displaying apparatus.

8. A computer-readable storage medium storing a program for causing a computer to perform a backlight controlling method which is performed by a backlight controlling apparatus which controls a backlight in a displaying apparatus for displaying image frames based on image data at a display frame rate which is double an input frame rate, wherein the program causes the computer to:

input original image data of the input frame rate;

generate intermediate image data corresponding to an intermediate image frame based on the original image data;

determine a light emission period and a light emission intensity for causing the backlight to emit light in accordance with whether the displaying apparatus displays an original image frame based on the original image data or the generated intermediate image frame based on the intermediate image data generated based on the original image data such that (i) a first light emission period of the backlight for displaying the original image frame based on the original image data is shorter than a second light emission period of the backlight for displaying the intermediate image frame based on the intermediate image data, (ii) a first light emission intensity of the backlight for displaying the original image frame based on the original image data is higher than a second light emission intensity of the backlight for displaying the intermediate image frame based on the intermediate image data, and (iii) a first luminance integrated value defined based on integrating the first light emission intensity by the first light emission period is approximately equal to a second integrated value defined based on integrating the second light emission intensity by the second light emission period; and

in a case where the displaying apparatus displays image frames at the display frame rate which is double the input frame rate of the original image data, perform control to cause the backlight to emit light at the first light emission intensity for the first light emission period for displaying the original image frame based on the original image data on the displaying apparatus, and cause the backlight to emit light at the second light emission intensity for the second light emission period for displaying the intermediate image frame based on the intermediate image data generated based on the original image data on the displaying apparatus.

9. A backlight controlling apparatus which controls a backlight used in a displaying apparatus for displaying an image frame based on image data, comprising:

an input unit configured to input the image data; and

a controlling unit configured to perform control to cause the backlight to emit light at a first light emission intensity L for a first time period, and cause the backlight to emit light continuously at a second light emission intensity M lower than the first light emission intensity L for a second time period longer than the first time period such that a first integrated value defined based on integrating the first light emission intensity L by the first time period is approximately equal to a second integrated value defined based on integrating the second light emission intensity M by the second time period, in a period for displaying one image frame based on the image data on the displaying apparatus, and perform control to cause the backlight not to emit light for a third time period between the first time period and the second time period.

10. The backlight controlling apparatus according to claim 9, wherein the backlight is caused to emit light twice or more at the second light emission intensity M every time the backlight is caused to emit light once at the first light emission intensity L.

11. The backlight controlling apparatus according to claim 9, wherein the controlling unit controls the backlight in a scanning manner.

12. The backlight controlling apparatus according to claim 9, wherein the controlling unit independently controls each block in the backlight of a direct-beneath type.

13. The backlight controlling apparatus according to claim 9, wherein the controlling unit simultaneously blinks a whole surface of the backlight.

14. The backlight controlling apparatus according to claim 9, wherein the controlling unit performs the control to cause the backlight to intermittently emit light at least either at a time when emitting light at the first light emission intensity L or at a time when emitting light at the second light emission intensity M.

15. The backlight controlling apparatus according to claim 9, wherein the controlling unit controls to continuously change luminance at least either at a time when emitting light at the first light emission intensity L or at a time when emitting light at the second light emission intensity M.

16. A backlight controlling method which is performed by a backlight controlling apparatus which controls a backlight used in a displaying apparatus for displaying an image frame based on image data, comprising:

inputting the image data; and

performing control to cause the backlight to emit light at a first light emission intensity L for a first time period, and cause the backlight to emit light continuously at a second light emission intensity M lower than the first light emission intensity L for a second time period longer than the first time period such that a first integrated value defined based on integrating the first light emission intensity L by the first time period is approximately equal to a second integrated value defined based on integrating the second light emission intensity M by the second time period, in a period for displaying one image frame based on the image data on the displaying apparatus, and performing control to cause the backlight not to emit light for a third time between the first time period and the second time period.

17. A computer-readable storage medium storing a program for causing a computer to perform a backlight controlling method which is performed by a backlight controlling apparatus which controls a backlight used in a displaying apparatus for displaying an image frame based on input image data,

wherein the program causes the computer to perform control to cause the backlight to emit light at a first light emission intensity L for a first time period, and cause the backlight to emit light continuously at a second light emission intensity M lower than the first light emission intensity L for a second time period longer than the first time period such that a first integrated value defined based on integrating the first light emission intensity L by the first time period is approximately equal to a second integrated value defined based on integrating the second light emission intensity M by the second time period, in a period for displaying one image frame based on the image data on the displaying apparatus, and to perform control to cause to backlight not to emit light for a third time period between the first time period and the second time period.