Pepper's Cone: An Inexpensive Do-It-Yourself 3D Display

UIST 2017

Xuan Luo, Jason Lawrence, Steven M. Seitz





Our 3D display consists of (a) an iPad, a thin hollow plastic cone, and a rotatable base. The nickel at the base provides stability. (b-c) As the user rotates the display, the system renders a perspective-correct image for their point of view that gives a convincing impression of a 3D object suspended inside the cone. This provides a very simple way of interactively examining a 3D scene for a fraction of the cost of alternative volumetric or light field displays and doesn't require the use of special glasses. (d) In addition, the system can be extended to produce correct binocular cues by incorporating stereoscopic rendering and glasses.


This paper describes a simple 3D display that can be built from a tablet computer and a plastic sheet folded into a cone. This display allows naturally viewing a three-dimensional object from any direction over a 360-degree path of travel without the use of a head mount or special glasses. Inspired by the classic Pepper's Ghost illusion, our approach uses a curved transparent surface to reflect the image displayed on a 2D display. By properly pre-distorting the displayed image our system can produce a perspective-correct image to the viewer that appears to be suspended inside the reflector. We use the gyroscope integrated into modern tablet computers to adjust the rendered image based on the relative orientation of the viewer. The end result is a natural and intuitive interface for inspecting a 3D object. Our choice of a cone reflector is obtained by analyzing optical performance and stereo-compatibility over rotationally-symmetric conic reflector shapes. We also present the prototypes we built and measure the performance of our display through side-by-side comparisons with reference images.


  1. Pepper's Cone is highlighted on ACM Interactions Demo Hour (ACM Library)!
  2. Pepper's Cone - An Easy 3D Display by iProgrammer.
  3. Inexpensive Display Jumps to Life by Hack a Day
  4. Pepper's Cone on Hacker News front page :D Welcome to put your comments here.