Patent ID: 7538907

Claim:
An apparatus for reading an image on a medium to be read, comprising: a light emitting device that emits light to illuminate the medium; a light receiving device, including a plurality of light receiving elements aligned with each other, that receives a reflected light from the medium via the plurality of light receiving elements; and a controller that obtains light sensitive signals from the respective plurality of light receiving elements in association with a respective plurality of pixels of the image which correspond to the respective plurality of light receiving elements, and that reads the image based on the obtained light sensitive signals, wherein the controller: causes, prior to a normal reading operation of the image, the light emitting device to perform a light emission, obtains the plurality of light sensitive signals from the plurality of light receiving elements, respectively, in response to the light emission, and determines that, based on the obtained plurality of light sensitive signals, at least one of the light emitting device and the light receiving device malfunctions when a consecutive number of abnormal pixels existing adjacent to each other reaches a predetermined reference value.