The theoretical structure for generating floating images from laser-ionized air is described and tested. A sensor mechanism by which users can interact with these images via touch is also proposed. The image-projection and touch feedback system uses a low-power femtosecond laser to ionize the air to create images and senses tactile interactions by detecting the laser echo. This method can be used for detecting a touch signal that changes the image position and for determining the location of a touch via triangulation. The proposed system can be applied in holographic projection imaging, fog-screen imaging, and laser imaging combined with ionized air. The holographic projection image or fog imaging screen is used to form a basic image, and the laser-ionized air is used to form images for touch interactions and buttons.