Normalized half-light radii R_1/2/R_in (red and green for 13 and 8.5 μm, respectively), plotted against UV luminosity L, defined as 6 νL_ν(5500 Å) (Kishimoto et al. 2007). The red and green dotted lines are power-law fits to R_1/2/R_in at 13 μm and 8.5 μm, respectively. The normalized radii become more compact in the objects having the central engine with a higher UV luminosity. Also shown in purple are thin-ring radii at 2.2 μm normalized by R_in for the sample observed with the KI (Kishimoto et al. 2011), including two overlapping objects. The gray dotted horizontal line indicates radius = R_in.