The present invention relates to an image processing system and an image processing method, an image pickup apparatus and an image pickup method, and an image display device and an image display method, which can faithfully pick up and display the colors of an object. Slit light of an optical image of the object that has passed through a slit 42 is divided into a spectrum by a light divider 43. A light sensor 44 outputs image data based on the spectrum of the slit light of the optical image of the object. A micromirror array 74 causes the exiting of reflection light formed by extracting spectrum portions based on the image data from a spectrum of incident white light from a light divider 73. The spectrum portions of the reflection light exiting from the micromirror array 74 are synthesized by a spectrum synthesizer 77 and are projected onto a screen 111. The present invention is applicable to the image processing system.