Patent ID: 8928574
Filing Date: 2015-01-06
Classification: G09G

Abstract:
1. A liquid crystal display device that has a backlight device including two illuminating portions for individually illuminating each of partial areas which is obtained by dividing a display area of a liquid crystal panel with a plurality of liquid crystal elements into two parts from behind, a backlight control portion sequentially intermittently lighting each of the illuminating portions in conjunction with writing of a video signal to the liquid crystal elements corresponding to the respective partial areas in the liquid crystal panel, and a motion vector detecting portion detecting a motion vector based on the video signal, comprising: an elemental image area detecting portion for detecting an elemental image area where the motion vector detected by the motion vector detecting portion equals to or greater than predetermined magnitude set in advance from the partial areas for each of the partial areas; and an intermittent lighting timing control portion for controlling timing of intermittent lighting of the illuminating portion by the backlight control portion such that, if the elemental image area detecting portion detects the elemental image area only in one of the partial areas, a turn-off period is provided for a predetermined time in the middle of a period between the start of writing of a video signal to the liquid crystal elements corresponding to the elemental image area detected by the elemental image area detecting portion and the elapse of a response time of the liquid crystal elements based on timing of the start of writing of a video signal to the liquid crystal elements corresponding to the elemental image area and the two illuminating portions are alternatively turned on, and also if the elemental image area detecting portion detects the elemental image area in each of the partial areas, a turn-off period is provided for a predetermined time in the middle of a period between the start of writing of a video signal to the liquid crystal elements corresponding to the elemental image and the elapse of until a response time of the liquid crystal elements in each of the partial areas based on timing of the start of writing of a video signal to the liquid crystal elements corresponding to each of the elemental image areas.