直反式感測器的設計與研究應用於近距及遠距偵測之三維互動系統

Abstract

3D立體技術顯示日漸普及，越來越多家用電視將其列為標準功能，讓消費者擁有不同於傳統平面顯示的視覺饗宴。甚至近年來也有廠商陸續推出了3D手機、3D相機等行動裝置，更確立了3D顯示技術在未來的發展。為了提供更直覺的使用者體驗，傳統平面式的人機介面系統也勢必發展為立體式的3D互動系統，讓使用者能直覺地與立體影像直接互動。在較大尺寸的顯示器上相機式互動系統已成為主流，然而在小尺寸顯示器如手機、平板電腦等行動裝置卻還未見到相對應的成熟產品。 傳統相機式互動系統利用多相機視角的不同來計算目標物位置，但近距離卻受限於視角死角而無法偵測，故僅用於大尺寸顯示器等中、長距離的互動上，而未見於小尺寸顯示器。然而目前已有少數研究以內嵌光感測元件為架構來實現行動裝置上的3D互動系統，但內嵌光感測元件靈敏度的限制造成其系統最大工作範圍僅約5 cm，對於實用性而言略顯不足。 本論文以相機式系統為基礎，將感測器分別安裝於顯示器角落，並加入反射層至感測器結構中使其成為直反式感測元件，因此可以改變感測到的部分視角，得以偵測近距離，讓相機式3D互動系統也可實現於行動裝置上，且改善內嵌光感測元件系統在工作範圍上的不足。在實驗中本系統以八吋平板電腦的顯示器大小為架構，支援的最大工作範圍達到10 cm，位置解析度達0.2 cm。

3D technology has been widely spread in recent years. As the way receiving information changing from 2D to 3D, the human-machine interface should also be improved to supply a more intuitive interaction. Camera-based interaction system has been used on larger display for years; however, we do not see a sophisticated corresponding product on smaller display like mobile device. There are several ways to achieve 3D interaction system. Some researchers dedicated in embedded-photosensor-based system for mobile device, but its maximum working range is slightly insufficient. In a traditional camera-based system, sensors are setting on different positions, and the target can be located by epipolar geometry. Nevertheless, it is failed due to limited field of view of sensors in near range. In this thesis, we propose a 3D interaction system for mobile device. The system is basically a camera-based system but with modified architecture. We designed a reflecting layer inserted into the sensor structure to reorient its field of view, enabling the camera-based system to work in near field. Finally, the concept was verified on a virtual 8-inch display. The maximum working range was 10 cm and the spatial resolution was 0.2 cm at least. In addition, we also found that the proposed system can support depth sensing in far field up to 50 cm.