We propose a large screen 3D display which enables multiple viewers to see simultaneously without special glasses. In prior researches, methods of using a projector array or a swinging screen were proposed. However, the former has difficulty in installing and adjusting a large number of projectors and the latter cases occurrence of vibration and noise because of the mechanical motion of the screen. Our proposed display consists of a wavelength modulation projector and a spectroscopic screen. The screen shows images of which color depends on viewing points. The projector projects binary images to the screen in time-division according to wavelength of projection light. The wavelength of the light changes at high-speed with time. Therefore, the system can show 3D images to multiple viewers simultaneously by projecting proper images according to each viewing points. The installation of the display is easy and vibration or noise are not occurred because only one projector is used and the screen has no mechanical motion. We conducted simulation and confirmed that the proposed display can show 3D images to multiple viewers simultaneously.