We demonstrate the construction and utilization of an affordable apparatus using readily available materials to accurately measure in a quantitative manner the wavelengths reflected by a compact disc (CD) under skimming light rays. In fact, only a limited number of wavelengths can be revealed when light rays from a white lamp are directed at a CD (or a DVD) in a manner that specifically selects the rays that graze the surface of the horizontally held disc. We compare the results with the ones obtained with a commercial spectrometer, finding that they are in good agreement among them and with the theoretical predictions.

中文翻译：

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低成本测量光盘在略读光线下反射的“共振”波长


我们展示了一种经济实惠的设备的构造和利用，使用容易获得的材料以定量方式精确测量光盘（CD）在略读光线下反射的波长。事实上，当来自白灯的光线以专门选择掠过水平放置的光盘表面的光线的方式照射到 CD（或 DVD）时，只能显示有限数量的波长。我们将结果与商用光谱仪获得的结果进行比较，发现它们之间以及理论预测非常一致。