First panel: edge-on galaxy NGC 4565, which hosts a prominent peanut-shaped bar, in magnitude scale with range 17−24 μ_{3.6 μm}(AB). The galaxy has been rotated so that the major axis appears horizontal in the image. The blue box roughly covers the bar region and extends vertically as far as z_s, which is the height above which 90% of the light emission comes from the thick disk component. Second panel: disk scale height estimated from the line-of-sight vertical dispersion. The continuous, dashed, and dotted blue lines correspond to the resulting h_z integrating up to z_s, 1.5z_s, and 0.5z_s, respectively. For the first case, the black dashed horizontal line shows the mean h_z outside the range of the peanut-shaped bar. The horizontal lines trace the thin disk h_z estimated from the fits to the vertical luminosity profiles (red). The resulting Q_T profiles from the different disk scale heights (solid blue, dashed black, and dotted red lines; with the meaning indicated in the legends) are shown in the lower right plot.