Display device and driving method thereof

Patent metadata

Field	Value
Publication number	US-9972264-B2
Application number	US-201615261345-A
Country	US
Kind code	B2
Filing date	Sep 9, 2016
Priority date	Mar 11, 2014
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A display device includes a processor including a first display mode in which the processor displays the image on the display screen from an internal image data after the processor receives a first control signal, and a second display mode in which the processor displays the image on the display screen from the image data received by the processor after the processor receives a second control signal. A luminance adjuster adjusts a display luminance based on the internal image data corresponding to a final frame immediately before switching from the first display mode to the second display mode to a display luminance lower than a display luminance of the internal image data of another frame in the first display mode. In the final frame, the image is displayed based on the internal image data in which the display luminance is adjusted by the luminance adjuster.

First claim

What is claimed is:

1. A display device comprising:
a processor that performs processing on each frame of image data that includes plural frames, the display device displaying an image on a display screen based on the image data processed by the processor, wherein the processor receives the image data, a first control signal indicating a command to stop output of the image data, and a second control signal indicating a command to perform the output of the image data;
a memory in which the image data received immediately before stop of transmission of the image data is stored as internal image data; and
a luminance adjuster that adjusts a display luminance based on the internal image data transferred from the memory,
wherein the processor includes: a first display mode in which the processor displays the image on the display screen from the internal image data after the processor receives the first control signal; and a second display mode in which the processor displays the image on the display screen from the image data received by the processor after the processor receives the second control signal,
wherein the luminance adjuster adjusts a display luminance based on the internal image data corresponding to a final frame immediately before switching from the first display mode to the second display mode to a display luminance lower than a display luminance of the internal image data of another frame in the first display mode, and
in the final frame immediately before switching from the first display mode to the second display mode, the image is displayed on the display screen based on the internal image data in which the display luminance is adjusted by the luminance adjuster.

2. The display device according to claim 1 , further comprising a calculator that calculates a blanking period from a writing end time point of the internal image data corresponding to the final frame immediately before the switching from the first display mode to the second display mode to a writing start time point of the image data corresponding to the initial frame immediately after the switching from the first display mode to the second display mode,
wherein the luminance adjuster adjusts the display luminance based on the internal image data corresponding to the final frame immediately before switching from the first display mode to the second display mode according to the blanking period calculated by the calculator.

3. The display device according to claim 2 , wherein the luminance adjuster includes a conversion circuit that converts a grayscale of the internal image data such that the display luminance based on the internal image data corresponding to the final frame immediately before switching from the first display mode to the second display mode is lower than the display luminance based on the internal image data corresponding to another frame, and
the conversion circuit converts the grayscale of the internal image data into a lower grayscale as the blanking period calculated by the calculator is lengthened.

4. The display device according to claim 3 , wherein the luminance adjuster includes a first conversion circuit that converts the grayscale of the internal image data corresponding to a frame except for the final frame in the first display mode and a second conversion circuit that converts the grayscale of the internal image data corresponding to the final frame in the first display mode, and
the second conversion circuit converts the grayscale into a grayscale lower than the grayscale converted by the first conversion circuit.

5. The display device according to claim 4 , wherein the luminance adjuster switches between the first conversion circuit and the second conversion circuit in a vertical blanking period.

6. A display device comprising:
a processor that performs processing on each frame of image data that includes plural frames, the display device displaying an image on a display screen based on the image data processed by the processor, wherein the processor receives the image data, a first control signal indicating a command to stop output of the image data, and a second control signal indicating a command to perform the output of the image data;
a memory in which the image data received immediately before stop of transmission of the image data is stored as internal image data; and
a luminance adjuster that adjusts a display luminance based on the received image data,
wherein the processor includes: a first display mode in which the processor displays the image on the display screen from the internal image data after the processor receives the first control signal; and a second display mode in which the processor displays the image on the display screen from the image data received by the processor after the processor receives the second control signal,
wherein the luminance adjuster adjusts a display luminance based on the image data corresponding to an initial frame immediately after switching from the first display mode to the second display mode to a display luminance higher than a target display luminance, and
in the initial frame immediately after switching from the first display mode to the second display mode, the image is displayed on the display screen based on the image data in which the display luminance is adjusted by the luminance adjuster.

7. The display device according to claim 6 , wherein the luminance adjuster adjusts the display luminance of the image data corresponding to the initial frame immediately after switching from the first display mode to the second display mode and the image data corresponding to at least one frame subsequent to the initial frame to the display luminance higher than the target display luminance, respectively, and adjusts the display luminance of a plurality of pieces of the image data such that the display luminance come close to the target display luminance in a stepwise manner.

8. The display device according to claim 6 , further comprising a calculator that calculates a blanking period from a writing end time point of the internal image data corresponding to a final frame immediately before the switching from the first display mode to the second display mode to a writing start time point of the image data corresponding to the initial frame immediately after the switching from the first display mode to the second display mode,
wherein the luminance adjuster adjusts the display luminance based on the image data corresponding to the initial frame immediately after switching from the first display mode to the second display mode according to the blanking period calculated by the calculator.

9. The display device according to claim 8 , wherein the luminance adjuster includes a conversion circuit that converts a grayscale of the image data such that the display luminance based on the image data corresponding to the initial frame immediately after switching from the first display mode to the second display mode is higher than a target display luminance, and
the conversion circuit converts the grayscale of the image data into a higher grayscale as the blanking period calculated by the calculator is lengthened.

10. The display device according to claim 9 , wherein the luminance adjuster includes a first conversion circuit that converts the grayscale of the image data corresponding to a frame except for the initial frame in the second display mode and a second conversion circuit that converts the grayscale of the image data corresponding to the initial frame in the second display mode, and
the second conversion circuit converts the grayscale into a grayscale higher than the grayscale converted by the first conversion circuit.

11. The display device

Assignees

• Panasonic Liquid Crystal Displ

Inventors

• Onishi Toshiki
• Ichiyama Iwane
• Inuzuka Tatsuhiro

Classifications

• G09G3/2025

  the sub-frames having all the same time duration · CPC title

• G09G2340/16

  Determination of a pixel data signal depending on the signal applied in the previous frame · CPC title

• G09G2310/08

  Details of timing specific for flat panels, other than clock recovery · CPC title

• G09G2320/0271

  Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping · CPC title

• G09G2320/0626

  for control of overall brightness · CPC title