利用發光二極體進行普朗克常數量測

The Measurement of the Planck's Constant by Using a Light-Emitting Diode

徐義鴻(Yi-Hung Hsu) ； 余進忠(Chin-Chung Yu)

《物理教育學刊》 20卷1期 (2019/07) Pp. 26-37

https://doi.org/10.6212/CPE.201907_20(1).0003

摘要

近代物理實驗中常以光電效應為基礎去進行普朗克常數的量測，為避免外界光線干擾，光電效應實驗往往需在暗室中進行，並需要一抽真空的光電二極管作為光電效應發生的環境，整組器材要價不斐，若本體以玻璃製作則容易撞擊破裂，因此不利存放及推廣的進行。本文中，我們改以發光二極體作為實驗對象，利用電致發光所提供的能量恰為光子能量來進行普朗克常數的推估，實驗器材係透過Arduino主板與相關電子元件來實現定電壓源及電壓、電流量測，並以手機APP進行實驗參數控制及接收數據。由於整個實驗系統以鋰電池供電且器材體積小，因此適合於普通教室進行實驗操作且不受環境影響。其成本低廉、體積小，十分符合推廣物理教育目的。

關鍵字

普朗克常數 ； 電致發光 ； 二極體 ； p-n接面 ； 內建電場 ； Arduino ； 電壓源 ； 電壓量測 ； 電流量測

並列摘要

In the experiments of the modern physics, the measurement of the Planck's constant is often based on the photoelectric effect. In order to avoid background light and air molecules, the photoelectric effect experiment needs to be carried out in an evacuated photodiode tube under a dark environment. In addition to the expensive price, if the photodiode tube is made of glass, it is not suitable for storage and education promotion. In this article, we use the electroluminescence or the current-to-voltage curve of a RGB light-emitting diode to measure the Planck constant. The experimental equipment is realized by the Arduino Nano board and related electronic components. The application of voltage and the measurements of the current and the voltage are controlled and monitored by the mobile App. Since the entire experimental equipment can be held in hand and powered by a lithium battery, it is suitable for doing the experiment in an ordinary classroom. Attributed to the low cost of the electronics, the experiment is also suitable for the education promotion.

並列關鍵字

Planck's constant ； electroluminescence ； diode ； p-n junction ； built-in electric field ； Arduino ； voltage source ； voltage measurement ； current measurement