US Patent 7251431 Image-reading apparatus and image forming apparatus

There is described an image reading apparatus, which employs the electric double layer. The image reading apparatus includes: an electric power source; an analogue image signal generating section that is coupled to the electric power source through a power line and converts an optical image to analogue image signals; an electric double layer capacitor that is coupled to the power line; a first switch that is coupled to both the electric power source and the electric double layer capacitor, in such a manner that the first switch is inserted between them; and a controlling section to control the first switch so as to make the first switch open in response to a output request signal for requesting an outputting operation of the analogue image signals.