The effective photosensitive area of a solid-state photosensor is controlled with a multitude of electrodes (E1, . . . , Ei, . . . , En) on top of an insulator layer (O) covering a semiconductor substrate (S). Photogenerated charge carriers move laterally under the influence of the voltage distribution on the various electrodes (E1, . . . , Ei, . . . , En), and they are collected at the two ends of the photosensor in diffusions (D1, D2). The voltage distribution on the electrodes (E1, . . . , Ei, . . . , En) is such that the voltage at the two furthermost electrodes (E1, En) is maximum (if photoelectrons are collected), minimum at an interior electrode (Ei), and monotonously decreasing in between. The lateral position of the electrode (Ei) with minimum voltage defines the effective photosensitive area of the photosensor. This photosensor can be used as pixel device in image sensors, either for dynamic exposure control, for optoelectronic mixing or for demodulation, such as required in optical time-of-flight range cameras.