Abstract: An image projection system is provided for projecting and displaying images at billboard or signboard scale in which a building display window defines the display aperture or viewing aperture of the image projection system for viewing projected images from outside the building. A deployable and retractible rear projection screen is positioned for deployment in the display aperture adjacent to the display window. A first timer is adjusted to actuate a screen motor and deploy the screen after daylight hours and actuate an image projector. Optical elements establish the focal plane of the projector at the display window aperture. A second timer sequentially advances the image projector for projection of sequential still images on the rear projection screen during selected time intervals of sufficient duration to avoid objectionable or distracting motion effects to viewers outside the building.