This dataset consists of temporal intensity autocorrelation (g2) and electric field autocorrelation (g1) curves measured by a Diffuse Correlation Spectroscopy (DCS) system from a two-layer optical phantom experiment. A total of 8 first layer (solid) thicknesses (0, 2.01, 3.28, 3.87, 4.65, 4.99, 5.96, and 8.08 mm) were each placed on top of the second layer (liquid). Each measurement was repeated 10 times, and 4 source-detector distances (10, 15, 20, 25 mm) were used. Mean and standard deviation of g1 and g2 were calculated over the 100 s measurement time span, and tau is the delay time. Please see 10.1371/journal.pone.0274258 for more details.