The present invention discloses an illumination device comprising: a first array of light sources comprising a number of a first type light sources and a number of a second type light sources; a second array of light sources comprising a number of said first type light sources; processing means adapted to controlling the first array by simultaneously controlling the intensity of all of said light sources light sources of the first array; controlling the second array by simultaneously controlling the intensity of all of the light sources light sources of the second array. The present invention discloses further a method for controlling such illumination device.