A novel volumetric 3D display system is presented. A series of helical slices of a 3D model is projected onto a spinning helical screen through a Digital Micro-mirror Device (DMD) as a fast Space Light Modulator (SLM). Due to the persistence of vision, human observers are able to perceive a true 3D volumetric image with physical depth cue by fusing together the successive helical slices into a 3D image. We emphasize the method for constructing a true 3D space using a spinning helical screen, analyze the volexlization approach based on Body-center Cubic (BCC) strategy, and design an algorithm to control DMD for projecting binary slices. Experimental results demonstrate that, a data reduction more than 40% is achieved by utilizing BCC sampling strategy, and the prototype is capable of displaying more complicated objects using DMD with μs-leveled response time, compared with the mirror-laser scheme. Objects can be displayed with true three dimensions and a fresh rate of 16 Hz in a half-cylinder display space with a diameter of 500 mm and a height of 250mm, and can be viewed from almost any angle without any special viewing aids.