本研究主要是針對廢液晶顯示器（Liquid Crystal Display, LCD）中發光二極體（Light-Emitting Diode, LED）背光源進行組成與鎵、銪、釔、鈰、釓、鋱、鎦有價金屬含量之分析。本研究規劃之工作內容如下：1. 收集廢LED/LCD；2. LCD組成拆解分析；3. LED背光源性質分析。本研究成果顯示，廢LCD樣品中之LED背光源重量百分比約佔其LCD螢幕總重的0.2%左右，另廢LED背光源樣品之水份、灰份及可燃份分別平均為0.41%、75.63%、23.96%，另廢LED背光源樣品中鎵、銪、釔、鈰金屬之全含量分別為738 mg/kg、64 mg/kg、18 mg/kg、9 mg/kg，而釓、鋱、鎦則未檢出，由此可知，廢LED背光源樣品中之有價金屬以鎵之含量最高。

In liquid crystal displays, light-emitting diode (LEDs) are commonly used to provide the backlight. This study analyzed the composition of the LED backlight in a waste liquid crystal display panel. In particular, the concentration of the valuable metals Ga, Eu, Y, Tb, Gd, Ce, and Lu in the LED backlight were determined. The LED backlight accounted for approximately 0.2% of the total weight of the waste LCS panel. Furthermore the moisture, ash, and combustible content of samples of the LED backlight were 0.41%, 75.63%, and 23.96%, respectively, and the Ga, Eu, Y, and Ce contents of the samples were 738, 64, 18, and 9 mg/kg, respectively. Metals such as Ga, Te, and Lu were not detected. Thus, the main constituent valuable metal in LED backlights is Ga.