Figure 3.

Experimental and numerical verifications of the theoretical models derived in Eqs. 25, 33 utilizing (a) a real-time and (b) a constant-time spatial encoding sequence. These experiments are extensions of the basic schemes illustrated in Figs. 2b, 2c, incorporating a number of extra purging gradients to ensure cleaner single-scan profiles. Rather than obtaining a full 2D interferogram, a single echo (i.e., the first t₂ point) was collected and Fourier analyzed to obtain the spatial profiles illustrated under each sequence. The experiments employed rf pulses sweeping from O_i=+50 toO_f=−50 kHz programmed on the basis of the Shinnar–LeRoux algorithm (Ref. ²⁷) with a finite envelop whose smoothing was not accounted for in the theoretical analyses (hence the departures of the experimental data at the sample’s edges). Further details on the numerical simulation procedure used to carry these comparisons are given in the Appendix.