Phenomenon of the change in velocity of propagation of monochromatic radiations in a medium as a function of the frequency of these radiations.
在介质中传播的单色光改变其传输速度的现象，并由该辐射的频率所决定的。
2
The propagation velocity of elastic wave with different frequencies in same medium is various, which is called dispersive problem of frequency.
相同介质中不同频率的弹性波传播速度是有差异的，即频散问题。
3
A new symplectic geometrical high frequency approximation method for solving the propagation of electromagnetic wave in an inhomogeneous medium is presented.