According to an example embodiment, a 3D providing set of shutter glasses are operated so as to extend their open times beyond a limited duration when the lighting source (e.g., backlighting unit) is providing light and to thus include in the image perceived by the user a proportional amount of ambient light that is directed to and through the shutter glasses during the extended opening time. In one embodiment, a timing control part determines an average grayscale value for each to be displayed image from the received image data and the timing control part correspondingly controls an open time for simultaneously opening the left eye shutter part and the right eye shutter part of the shutter glasses according to the determined average grayscale value of the image data.