Fig. 1: Algorithm for the image regression of inkjet-printed line impedance.

a Inkjet printing of silver nanoparticle ink on a glass substrate. b Impedance spectroscopy (IS) of inkjet-printed lines. The equivalent circuit is suggested with a typical Bode plot and Nyquist plot for sliver nanoparticles (AgNP) and pores of the inkjet-printed lines. The regions with only AgNP and with pores are colored in blue and red, respectively. c Image regression of the inkjet-printed lines. Optical microscopic images were used as input data. R₀, R₁, and C₁ from IS were used as labels. The CNN model was schematically depicted with its linear activation function to predict R₀, R₁, and C₁ values.