A second stacked product is configured with a flexible wiring sheet, and a stacked-element array supported by the flexible wiring sheet. To a biological-body side of the stacked-element array, a ground film is bonded, whereby a structurally reinforced third stacked product is produced. Then, the third stacked product is bent, whereby a curved stacked product is produced. In the bending procedure, in the ground film, a plurality of extension parts arranged along the θ direction are automatically formed.
