自然界中我们见到的各种复杂的振动现象，如光、声、电磁波等，都是由许多不同频率和不同振幅的简谐振动迭加而成的。例如，我们可以用分光镜或其它仪器把光波分解为不同强度和波长的单色光而形成光谱，根据光谱对入射的光波进行分析，研究它的组成。除了用物理的手段进行波谱分析之外，还发展 All kinds of complicated vibration phenomena that we have seen in nature, such as light, sound and electromagnetic waves, are made up of many simple harmonic vibrations of different frequencies and amplitudes. For example, we can use a spectroscope or other instrument to decompose the light into monochromatic light of different intensities and wavelengths to form a spectrum, and analyze the incident light wave according to the spectrum to study its composition. In addition to using the physical means of spectral analysis, but also developed