Abstract: A color document image reading device provides for inputting of a color image on an original document to various kinds of image processing apparatus. The color document image is decomposed into predetermined pixels, then photoelectrically converted into an electric signal, and then outputted with the pixels arranged time-serially. A filter has a plurality of color separation filter elements which are arranged in a flat configuration while being physically isolated from each other by a light-intercepting area having a predetermined width. The filter is driven by filter drive means in a reciprocal motion in a direction perpendicular to an optical axis, whereby any of the filter elements is brought into alignment with the optical axis. The filter is supported in such a manner as to be movable in a direction of movement of the filter drive means while being prevented from moving in the other directions.

Abstract: An apparatus for reading an image information of a colored original including an original supporting member, an optical system and a reading device for reading out the image information separated in at least two colors and for converting the optical information into the electric output. A standard reflection member for white balance is arranged within an illuminating range of the original supporting member and outside of an effective range for reading out of the original. Output levels of electric circuits for each separated colors are compensated dependent on electric outputs of the reading device regarding to the image information for separated colors of the light reflected from the standard reflection member.

Abstract: A sensor (S.sub.1) is provided in a reflector (23) which reflects light from a lamp (21) to illuminate an original document (24) for scanning. A light image of the document (24) is scanned by an optoelectronic scanning array (28) which produces video signals corresponding thereto. The sensor (S.sub.1) is so located as to receive light both directly from the lamp (21) and reflected from the document (24) so as to produce an output signal corresponding to a combined function of the background density of the document (24) and the intensity of the lamp (21). This sensor output is used to control the amplification factor of an amplifier (29) which amplifies the video signals so as to maintain a constant average level of the output thereof.The background level is removed from the video signals by a peak hold circuit (32) and an operational amplifier (34) which subtracts the video signals from the output of the peak hold circuit (32). The peak hold circuit (32) also combine the video signals with a reference value.