page 5
Standard geometric transcriptions show that half-wave length units (here traveling in the vertical direction) transfer that information directly and exactly into any orthogonal dimension... regardless of the angle Theta ... which I assume to be a phase-space component with the main attribute of being temporal as well as spatial. This is fixed and true regardless of Theta.
What occurs when Theta goes to zero is that both sides of the wave function contribute their information to a locus now in one less temporal state. The locus contains "wavelength-squared" information.
As for the general condition when Theta is greater than zero, the orthogonal wavefront can by itself be considered a dimensionally reduced portion of the total structure. That wavefront is the region of holographic wavefront information, chopped mid-flight, reduced by several dimensional components, yet recoverable by reinclusion of the reference beam which carries the residue spatial/temporal factors.