避免全彩LED面板錯誤點亮之個案研究

Abstract

在LED (Light-Emitting Diode)產業快速發展的今天，不論室內或室外LED廣告面板的使用已經越來越普及，然而目前為止沒有一套對於各家廠商發展的廣告板電路系統檢驗標準，因此在設計上可能會出現一些意料外的瑕疵。在本論文裡，我們與業界ODM (Original Design Manufacturer ) 廠商合作進行個案研究，找出其所設計之LED廣告板在非全面板同時點亮時會出現上下排與左右排錯誤點亮之原因，並且提出在波形與硬體設計上的修正方法並呈現修正結果。 第一章介紹合作廠商設計之室內全彩LED廣告板的特點，並簡介本文研究之LED廣告板架構。此架構為一塊顯示面板連接影像控制板，由電腦DVI (Digital Visual Interface) 連接阜將影像訊號輸入控制板再將畫面輸出至LED顯示板。本章最後，回顧LED廣告板電路設計、影像資料傳輸與FPGA波形設計之相關文獻。 第二章介紹室內用LED廣告板所使用的點矩陣型式LED模組，並分析其電路與規格。再說明合作廠商所設計的LED廣告板之電路系統─主板與控制板的系統架構。另外介紹此廣告板之特殊成像方向與針腳排列方式，此種成像方向與針腳排列方式使其具有比傳統廣告板更優良之散熱能力。 第三章先討論RGB三色LED混合做出顏色變化的方法。我們選用PWM (Pulse-Width Modulation)做為調光混色方式，並發展一套PWM對應畫素值之演算法，再將PWM演算法中得到的數值轉換為FPGA (Field Programmable Gate Array)輸出波形。最後解說此系統之畫面時序設計與FPGA輸出波形設計並解釋各種波形功用。 第四章分析錯誤點亮成因。其原因可分為軟體與硬體兩個部份。在完成分析後，本文提出修正方法並呈現修正後之結果。 第五章對研究成果進行總結，並提出未來改進之方向。

With the development of the light-emitting diode (LED) industry, outdoor and indoor LED panels are increasingly used for advertisements. To date, no inspection standard exists for testing LED panel circuits in Taiwan. Therefore, a number of unexpected errors may occur when designing LED panels. In this study, we collaborated with an original design manufacturer (ODM) company; our goal was to identify and correct lighting errors in full-color LED panels. In Chapter 1 of this study, we discuss related literature and describe the system structure of LED panels, which consist of a display panel and a control panel. Video signals are transmitted from the digital visual interface (DVI) port to the control panel, which converts the video signals into control signals. These control signals are then transmitted to the display panel to light the LEDs. Chapter 2 presents the circuit and specifications of the LED dot matrix module in the indoor LED panel and explains the circuit and system structure of the display panel and the control panel, which were designed by the ODM company. Furthermore, the pin arrangement of this LED panel differs from that of other LED panels and offers superior cooling circuit performance compared to other arrangements. Chapter 3 details the measures of the RGB-LED dimming control. We developed an algorithm to generate pulse-width modulation (PWM), which we used to dim the LEDs. Finally, in this chapter, we explain the functions of field-programmable gate array (FPGA) control signals and how to determine the clock signal for FPGA devices. In Chapter 4, we present an analysis of the factors that cause lighting errors, including software and hardware errors. After the analysis, we provide reasons and propose measures to correct lighting errors. Finally, we present the correction results. Chapter 5 provides our conclusion and recommendations for future research.