Printed Perforated Lampshades for Continuous Projective Images

Abstract

We present a technique for designing 3D-printed perforated lampshades, which project continuous grayscale images onto the surrounding walls. Given the geometry of the lampshade and a target grayscale image, our method computes a distribution of tiny holes over the shell, such that the combined footprints of the light emanating through the holes form the target image on a nearby diffuse surface. Our objective is to approximate the continuous tones and the spatial detail of the target image, to the extent possible within the constraints of the fabrication process.To ensure structural integrity, there are lower bounds on the thickness of the shell, the radii of the holes, and the minimal distances between adjacent holes. Thus, the holes are realized as thin tubes distributed over the lampshade surface. The amount of light passing through a single tube may be controlled by the tube's radius and by its direction (tilt angle). The core of our technique thus consists of determining a suitable configuration of the tubes: their distribution across the relevant portion of the lampshade, as well as the parameters (radius, tilt angle) of each tube. This is achieved by computing a capacity-constrained Voronoi tessellation over a suitably defined density function, and embedding a tube inside the maximal inscribed circle of each tessellation cell. The density function for a particular target image is derived from a series of simulated images, each corresponding to a different uniform density tube pattern on the lampshade.

A computational approach for spider web‐inspired fabrication of string art

“…In computer graphics and related fields, several exciting works have recently investigated unconventional, inspiring computational fabrication of objects and art creation, such as knitting, thermoforming, stippled prints with drone, perforated lampshades, spray painting, airbrush system, balloons, inflatable structures, tile decors, and kites . Our work belongs to this line of works, and we present a fully automatic system to fabricate spider web‐inspired string art pieces.…”

State of the Art on Stylized Fabrication

“…The work of Zhao et al . [ZLW*16], instead, automatically generates 3D printable perforated lampshades that are able to project the luminance of a provided input image by modulating light and shadow. This technique accounts for the light emitted from a light bulb inside a static lampshade and optimizes the position and orientation of tubular holes on its surface, which control the light passage.…”

String Art: Towards Computational Fabrication of String Images

“…Recently, Zhao et al [ZLW*16] proposed an approach for the computation of perforated lampshades for continuous projective images which emerge as shadows on the walls if a lamp is lit. Another very interesting method proposed by Schüller et al [SPSH14] creates so‐called appearance‐mimicking surfaces, where an image is distributed across different geometric objects and emerges as a relief only if viewed from a very specific position.…”