A liquid crystal display device, comprising: a liquid crystal display panel; a light source configured to provide the liquid crystal display panel with a light; a timing controller adapted to output a light source control signal according to a normal luminance value and a luminance correction value, said timing controller comprising a vertical blank detector circuit and a luminance correction value calculator circuit; the vertical blank detector circuit being configured to calculate a counting value of a vertical blank period of a frame by counting a synchronization signal; the luminance correction value calculator circuit being configured to calculate a luminance correction value by comparing the counting value of the vertical blank period with a plurality of reference counting values (CV1...CV6); and a light source driver configured to generate a light source driving signal (LS_B1...LS_BN) according to the light source control signal and provide the light source driving signal (LS B1...LS BN) to the light source such that the light source driving signal (LS B1... LS_BN) has a normal level corresponding to the normal luminance value in an active period of the frame and has the correction level corresponding to the luminance correction value in the vertical blank period wherein the luminance correction value calculator circuit is configured to maintain the normal luminance value corresponding to the active period of the frame when the counting value of the vertical blank period is smaller than a smallest reference counting value (CV1...CV6) of the vertical blank period, to obtain the luminance correction value when the counting value of the vertical blank period is equal to or greater than one of the reference counting values, and to change to the normal luminance value corresponding to the active period of a next frame when a start signal corresponding to the next frame rises, characterized in that the luminance correction value calculator includes a histogram analyzer, a lookup table and a calculator, the histogram analyzer being adapted to analyze image data to calculate a representative grayscale, the lookup table storing a plurality of sample correction values corresponding to sample reference counting values and sample grayscales, the calculator being adapted to determine each of the normal luminance value and the luminance correction value corresponding to the representative grayscale and the counting value based on the look-up table. a liquid crystal display panel; a light source configured to provide the liquid crystal display panel with a light; a timing controller adapted to output a light source control signal according to a normal luminance value and a luminance correction value, said timing controller comprising a vertical blank detector circuit and a luminance correction value calculator circuit; the vertical blank detector circuit being configured to calculate a counting value of a vertical blank period of a frame by counting a synchronization signal; the luminance correction value calculator circuit being configured to calculate a luminance correction value by comparing the counting value of the vertical blank period with a plurality of reference counting values (CV1...CV6); and a light source driver configured to generate a light source driving signal (LS_B1...LS_BN) according to the light source control signal and provide the light source driving signal (LS B1...LS BN) to the light source such that the light source driving signal (LS B1... LS_BN) has a normal level corresponding to the normal luminance value in an active period of the frame and has the correction level corresponding to the luminance correction value in the vertical blank period wherein the luminance correction value calculator circuit is configured to maintain the normal luminance value corresponding to the active period of the frame when the counting value of the vertical blank period is smaller than a smallest reference counting value (CV1...CV6) of the vertical blank period, to obtain the luminance correction value when the counting value of the vertical blank period is equal to or greater than one of the reference counting values, and to change to the normal luminance value corresponding to the active period of a next frame when a start signal corresponding to the next frame rises, characterized in that the luminance correction value calculator includes a histogram analyzer, a lookup table and a calculator, the histogram analyzer being adapted to analyze image data to calculate a representative grayscale, the lookup table storing a plurality of sample correction values corresponding to sample reference counting values and sample grayscales, the calculator being adapted to determine each of the normal luminance value and the luminance correction value corresponding to the representative grayscale and the counting value based on the look-up table.