Time delay as a function of the wavelength calculated with ICCF method from the artificial light curves for the frequency break corresponding to timescales of 7.5 day (upper panel), 75 days (second panel), and 750 days (third panel). Model parameters: black hole mass 10⁸ M_⊙, Eddington ratio = 1.0, corona height = 5r_g, inclination angle = 30 degree, and luminosity is on the order of 10⁴⁵ erg s⁻¹. Black points and continuous line represents the delays expected from the disk response function.