Patent ID: 8482513
Filing Date: 2013-07-09
Classification: G09G

Abstract:
1. A liquid crystal display device, comprising: a liquid crystal display panel having a number of first scanning lines, a number of second scanning lines, a number of first video lines which cross said number of first scanning lines, and a number of second video lines which cross said number of second scanning lines; a first scanning line driving circuit for supplying a scanning voltage to said number of first scanning lines; a second scanning line driving circuit for supplying a scanning voltage to said number of second scanning lines; at least one first video line driving circuit for supplying a video voltage to said number of first video lines; and at least one second video line driving circuit for supplying a video voltage to said number of second video lines, said first video line driving circuit and said second video line driving circuit are provided along two sides of said liquid crystal display panel which face each other; a backlight having a number of light sources; and a light controlling circuit for controlling the turning on and off of said backlight; wherein said number of first scanning lines are divided into M groups where M is an integer of 2 or more (M≧2), said number of second scanning lines are divided into N groups where N is an integer of 2 or more (N≧2), the region of said backlight which corresponds to said number of first scanning lines is divided into M regions and the region which corresponds to said number of second scanning lines is divided into N regions, and said light controlling circuit turns off a jth region of said backlight (1≦j≦M) when said first scanning line driving circuit is supplying a selective scanning voltage to the first scanning lines within a jth group of said number of first scanning lines, turns on the jth region of said backlight when no selective scanning voltage is supplied to the first scanning lines within the jth group, turns off a kth region of said backlight (1≦k≦N) when at least one of said second scanning line driving circuits supplies a selective scanning voltage to the second scanning lines within a kth group of said number of second scanning lines, and turns on the kth region of said backlight when no selective scanning voltage is supplied to the second scanning lines within the kth group; wherein when the direction from said first video line driving circuit toward said second video line driving circuit is a first scanning direction and the direction from said second video line driving circuit toward said first video line driving circuit is a second scanning direction, the direction in which a selective scanning voltage is supplied from said first scanning line driving circuit to each scanning line of said number of first scanning lines in sequence is said first scanning direction, and the direction in which a selective scanning voltage is supplied from said second scanning line driving circuit to each scanning line of said number of second scanning lines in sequence is said second scanning direction; wherein one of the M regions of said backlight and one of the N regions of said backlight are adjacent to each other; wherein said light controlling circuit turns on both of the adjacent ones of the M and N regions of said backlight at the same time and turns off both of the adjacent ones of the M and N regions of said backlight at the same time; and wherein said light controlling circuit makes a period of turn on for both of the adjacent ones of the M and N regions of said backlight shorter than a period of turn on for the other regions of the M regions and the N regions of said backlight as a result of a delay in turn on time at the beginning of a frame for both of the adjacent ones of the M and N regions.