Modulation of the spectrum of a dye laser by spatial gratings of the refractive index of a substance placed inside the resonator

A study was made of the modulation of the coherent emission spectrum by spatial gratings of the refractive index, produced by the dye laser field in an absorbing medium inside the resonator. It was found that the frequencies of the reflection maxima of a nonlinear mirror resulting from the inhomogeneity of the refractive index along the direction of propagation of the light wave were in agreement with the frequencies satisfying the conditions for the maxima of interference reflection in the presence of an additional plane in the resonator.