Shadowless Projection Mapping for Tabletop Workspaces with Synthetic Aperture Projector

2026-03-12

AI Summary

This work addresses the challenge of shadow occlusion in conventional desktop projection mapping, which disrupts augmented reality experiences and multi-user interaction. The authors propose a synthetic aperture projection architecture based on a dense multi-projector array, incorporating offline blur compensation to mitigate resolution loss caused by subpixel misalignment—enabling high-quality, shadow-free projection with low latency without requiring real-time computation. For the first time, they establish a design framework centered on minimizing the “Sense of Projection” (SoP), integrating user perception studies to optimize system performance. This approach significantly reduces users’ awareness of the projected nature of the content, thereby enhancing both immersion and practical usability.

Technology Category

• Computer Vision: Computational Photography, Image & Video Synthesis
• Humans and AI: Game Design — Virtual Humans, NPCs and Autonomous Characters
• Intelligent Robots: Multimodal Perception & Sensor Fusion

Application Category

• User Modeling, Personalization and Recommendation: User privacy protection in personalized systems
• Responsible Web: Human-perceived consequences of algorithmic deployment on the web
• Search and Retrieval-Augmented AI: Personalized, context-aware and across-device search

Abstract

Projection mapping (PM) enables augmented reality (AR) experiences without requiring users to wear head-mounted displays and supports multi-user interaction. It is regarded as a promising technology for a variety of applications in which users interact with content superimposed onto augmented objects in tabletop workspaces, including remote collaboration, healthcare, industrial design, urban planning, artwork creation, and office work. However, conventional PM systems often suffer from projection shadows when users occlude the light path. Prior approaches employing multiple distributed projectors can compensate for occlusion, but suffer from latency due to computational processing, degrading the user experience. In this research, we introduce a synthetic-aperture PM system that uses a significantly larger number of projectors, arranged densely in the environment, to achieve delay-free, shadowless projection for tabletop workspaces without requiring computational compensation. To address spatial resolution degradation caused by subpixel misalignment among overlaid projections, we develop and validate an offline blur compensation method whose computation time remains independent of the number of projectors. Furthermore, we demonstrate that our shadowless PM plays a critical role in achieving a fundamental goal of PM: altering material properties without evoking projection-like impression. Specifically, we define this perceptual impression as ``sense of projection (SoP)'' and establish a PM design framework to minimize the SoP based on user studies.

Problem

• projection mapping
• occlusion shadows
• synthetic aperture
• sense of projection
• tabletop workspace

Innovation

• synthetic aperture projector
• shadowless projection mapping
• sense of projection
• blur compensation
• tabletop augmented reality