A matrix-type display device includes a display electrode board that has a plurality of pixel electrodes arranged into a matrix. A set of scan lines extend in parallel in one direction and a set signal lines extend in an orthogonal direction so that these lines are arranged between adjacent pixel electrodes. A spare line intersects at least some of the scan lines and/or said signal lines at each end of said set of lines so as to sandwich an insulating film therebetween, and a lead-out line is connected to one end of the spare line. The lead-out lines are connected to external connecting lines, which are outside of the display electrode board, so that the lead-out lines can be connected to each other through said connecting lines. Line breakdowns can be corrected and the correction of the breakdowns entails little or no increase in load capacity, electrical resistance, and noise with respect to the corrected line.