How to separate the diffraction image of liquid crystal polarization grating

As shown in the figure, this is the diffraction image of a liquid crystal polarization grating, which is respectively composed of zero-order, positive first-order and negative first-order images. In the case of only overlapping diffraction images, how should it be separated into three orders of diffraction images? enter image description here

I tried non-negative matrix decomposition, layer separation and other methods, but the three methods were not completely separated and the image information was lost. The separation results are as follows[enter image description here]