A display device comprising: a coordinate input device including a transparent substrate having detection electrodes (XSE, YSE) disposed in a transparent detection region corresponding to a contact position, the transparent substrate having first signal interconnects disposed in a region outside the detection region, the first signal interconnects having respectively one end connected to the detection electrodes (XSE, YSE) and being formed with first electrode terminals at the respective other end thereof, the first electrode terminals being arranged along one side of the substrate, and a flexible interconnect substrate connected to the first electrode terminals the flexible interconnect substrate used for supplying a driving signal to the detection electrodes (XSE, YSE) by way of the first signal interconnects and extracting a detection signal from the detection electrodes (XSE, YSE); and a display panel for image display in a display area based on a video signal from an external system, the coordinate input device being disposed on the display panel at the side of a display screen; wherein a light shielding plate and a protective plate are disposed on the coordinate input device, characterized in that the coordinate inputting device has a second signal interconnect disposed outside the first signal interconnects along the peripheral edge of the transparent substrate, the second signal interconnect surrounding the area where the detection region is included and the first signal interconnects are formed, the second signal interconnect having open opposite ends connected to a pair of the outermost terminals of the first electrode terminals for disconnection inspection at the open ends, the second signal interconnect is formed of a thin conductive film disposed along the peripheral edge portion of the transparent substrate, wherein the second signal interconnect is covered by the light shielding plate and is visually recognizable by an inspector before bonding of the display panel to the touch panel. a coordinate input device including a transparent substrate having detection electrodes (XSE, YSE) disposed in a transparent detection region corresponding to a contact position, the transparent substrate having first signal interconnects disposed in a region outside the detection region, the first signal interconnects having respectively one end connected to the detection electrodes (XSE, YSE) and being formed with first electrode terminals at the respective other end thereof, the first electrode terminals being arranged along one side of the substrate, and a flexible interconnect substrate connected to the first electrode terminals the flexible interconnect substrate used for supplying a driving signal to the detection electrodes (XSE, YSE) by way of the first signal interconnects and extracting a detection signal from the detection electrodes (XSE, YSE); and a transparent substrate having detection electrodes (XSE, YSE) disposed in a transparent detection region corresponding to a contact position, the transparent substrate having first signal interconnects disposed in a region outside the detection region, the first signal interconnects having respectively one end connected to the detection electrodes (XSE, YSE) and being formed with first electrode terminals at the respective other end thereof, the first electrode terminals being arranged along one side of the substrate, and a flexible interconnect substrate connected to the first electrode terminals the flexible interconnect substrate used for supplying a driving signal to the detection electrodes (XSE, YSE) by way of the first signal interconnects and extracting a detection signal from the detection electrodes (XSE, YSE); and a display panel for image display in a display area based on a video signal from an external system, the coordinate input device being disposed on the display panel at the side of a display screen; wherein a light shielding plate and a protective plate are disposed on the coordinate input device, the coordinate inputting device has a second signal interconnect disposed outside the first signal interconnects along the peripheral edge of the transparent substrate, the second signal interconnect surrounding the area where the detection region is included and the first signal interconnects are formed, the second signal interconnect having open opposite ends connected to a pair of the outermost terminals of the first electrode terminals for disconnection inspection at the open ends, the second signal interconnect is formed of a thin conductive film disposed along the peripheral edge portion of the transparent substrate, wherein the second signal interconnect is covered by the light shielding plate and is visually recognizable by an inspector before bonding of the display panel to the touch panel.