A light source device comprising: - a reflector extending in a lengthwise direction; - a plurality of reflector supports that are arranged at an interval along the lengthwise direction and support the reflector; and - a rod-shaped light source (308, 356, 357) or an array light source extending in the lengthwise direction, wherein the reflector is placed opposite the rod-shaped light source (308, 356, 357) or the array light source, and is adapted to reflect light output from a side face of the rod-shaped light source (308, 356, 357) or the array light source, characterized in that each of the plurality of reflector supports is integral with a planar member that supports the plurality of reflector supports, and each of the plurality of reflector supports is formed at a designated angle with respect to a widthwise direction on the planar member by bending one end of the planar member along the lengthwise direction, wherein the planar member includes a plurality of planar ends extending from each portion other than the plurality of reflector supports on the one end along the lengthwise direction, the plurality of planar ends formed by bending the one end of the planar member along the lengthwise direction, the planar member including a plurality of cut-outs for forming the plurality of reflector supports and the plurality of planar ends, and the length of the planar ends (364, 365) in the lengthwise direction is longer than the length of the reflector supports in the lengthwise direction, and the plurality of planar ends (364, 365) include screw holes as a connection interface member for attaching to a carriage of an image scanning device. - a reflector extending in a lengthwise direction; - a plurality of reflector supports that are arranged at an interval along the lengthwise direction and support the reflector; and - a rod-shaped light source (308, 356, 357) or an array light source extending in the lengthwise direction, wherein the reflector is placed opposite the rod-shaped light source (308, 356, 357) or the array light source, and is adapted to reflect light output from a side face of the rod-shaped light source (308, 356, 357) or the array light source, each of the plurality of reflector supports is integral with a planar member that supports the plurality of reflector supports, and each of the plurality of reflector supports is formed at a designated angle with respect to a widthwise direction on the planar member by bending one end of the planar member along the lengthwise direction, wherein the planar member includes a plurality of planar ends extending from each portion other than the plurality of reflector supports on the one end along the lengthwise direction, the plurality of planar ends formed by bending the one end of the planar member along the lengthwise direction, the planar member including a plurality of cut-outs for forming the plurality of reflector supports and the plurality of planar ends, and the length of the planar ends (364, 365) in the lengthwise direction is longer than the length of the reflector supports in the lengthwise direction, and the plurality of planar ends (364, 365) include screw holes as a connection interface member for attaching to a carriage of an image scanning device.