Abstract: A display device (506) is driven in a number of sub-fields. Each of the sub-fields is for outputting a respective illumination level by the display device. In each sub-field, a pixel of the displayed image may emit an amount of light corresponding to the particular sub-field, depending on whether it is switched on or not. A required intensity level of the pixel is realized by selecting an appropriate combination of sub-fields in which the pixel is switched on. A selection is made from the possible intensity levels that can be generated by all possible combinations of sub-fields. This selection contains those intensity levels that can be generated by sub-fields that are temporally close together, thus causing that the light of a pixel is emitted during a relatively short period. The image display unit (300) has a look-up table (306) for storing the combinations of sub-fields for the respective selected intensity levels.