用动画分别展示出3种不同波形的传播方式。分别有：1.单色平面波；2.双色平面波叠加；3.两个球面波相干叠加。-This file show the animinations of three different waves, which includes: 1.monochromatic plane wave 2.superposition of two monochromatic plane waves 3.the coherence of two spheric waves.