光學式多點觸碰板

Abstract

觸控面板的技術種類相當多，一般來說可依照所應用的尺寸做大致上的技術應用區隔。在小尺寸應用，如PDA (Personal Digital Asistant)、手機等方面，目前絕大多數是採用電阻式觸控面板；新興的技術應用則是由iPhone所帶動起的投射電容式觸控面板。中尺寸方面傳統上則由紅外線式、表面聲波式或是表面電容式為主，應用在POS (Point Of Sale)、 kiosk、ATM (Automated Teller Machine)等工業電腦領域。而在大尺寸應用上則為光學式以及影像識別式為主，大多數應用在展覽、20吋以上的液晶螢幕等等。影像識別式其原理與光學式類似，不同在於相機擺放的位置，影像識別式也依據光源的不同而有不同的技術產生，例如FTIR (Frustrated Total Internal Reflection)、DI (Diffused Illumination)、LLP (Laser Light Plane)、DSI (Diffused Surface Illumination)、LED-LP (Light-Emitting Diode-Light Plane)；本文主要探討的內容包含如何透過相機所擷取到的畫面對齊做處理以利取得接觸在觸控版上的手指，以及影像識別式所有的類別中都會遇到的手指太靠近而只產生一個blob的問題，本文的方法可以有效率當手指太靠近時分割出所在手指的位置！

Multi-touch panels are very popular. Many kinds of multi-touch panel technologies exist, such as analog resistive, digital resistive, surface acoustic wave, surface capacitive, projected capacitive, infrared, and so on. In the small size panels such as PDA, smart phone, the resistive and capacitive technologies are often used. To the middle size panels such as 20” LCD (Liquid Crystal Display) screen, POS, kiosk, ATM, the resistive, capacitive, infrared technologies are often used. Moreover, we will focus on the big size panels such as 50” upward panel or wall size panel. The big-size panel technologies are mainly optics-based where we have a camera to retrieve each frame for the touch process and a light source like infrared to help camera to retrieve a better frame. Moreover, we will propose a method to solve the finger proximity problem and add the pressure information to the fingers. According to our experimental results, our approaches can find out the finger we want, solve the finger proximity issue and add virtual pressure information to the fingers.