A driving method for a liquid crystal display device assembly that includes a transmissive-type liquid crystal display device, a planar light source device including P×Q planar light source units, and a drive circuit that drives the two devices is disclosed. The driving method includes the step of, when the value of an input signal input into the drive circuit is indicated by x, in each of the display area units, when the value x of the input signal for any of the pixels is greater than or equal to a predetermined value, such a value being indicated by xU-max, controlling the luminance level of the planar light source unit corresponding to the display area unit so that luminance levels of the pixels, assuming that the control signal corresponding to the input signal having a value greater than the value xU-max is supplied to the pixels, can be obtained.