physical

A number of projects within the computer graphics, computer vision, and human-computer interaction communities have recognized the value of using projected structured light patterns for the purposes of doing range finding, location dependent data delivery, projector adaptation, or object discovery and tracking. However, most of the work exploring these concepts has relied on visible structured light patterns resulting in a caustic visual experience. In this work, we present the first design and implementation of a high-resolution, scalable, general purpose invisible near-infrared projector that can be manufactured in a practical manner. This approach is compatible with simultaneous visible light projection and integrates well with future Digital Light Processing (DLP) projector designs -- the most common type of projectors today. By unifying both the visible and non-visible pattern projection into a single device, we can greatly simply the implementation and execution of interactive projection systems. Additionally, we can inherently provide location discovery and tracking capabilities that are unattainable using other approaches.

ThinSight is a novel optical sensing system, fully integrated into a thin form factor display, capable of detecting multi-ple fingers placed on or near the display surface. We describe this new hardware in detail, and demonstrate how it can be embedded behind a regular LCD, allowing sensing without degradation of display capability. With our approach, fingertips and hands are clearly identifiable through the display. The approach of optical sensing also opens up the exciting possibility for detecting other physical objects and visual markers through the display, and some initial experiments are described. We also discuss other novel capabilities of our system: interaction at a distance using IR pointing devices, and IR-based communication with other electronic devices through the display. A major advantage of ThinSight over existing camera and projector based optical systems is its compact, thin form-factor making such systems even more deployable. We therefore envisage using ThinSight to capture rich sensor data through the display which can be processed using computer vision techniques to enable both multi-touch and tangible interaction.