Abstract: A method and apparatus which writes image information into a memory and reads the image information out of the memory using different synchronizing signals. A first synchronizing signal which is used to write scanned image data into the memory is generated to have a predetermined regularity, for example using a clock signal. The second synchronizing signal is based on an output of a photosensor which detects laser light reflecting off a polygonal mirror and is based on the rotating speed of the motor. The image information in the memory is read out in synchronism with the writing of the image information by the laser beam and polygonal mirror onto the photoconductive element using the second synchronizing signal. Therefore, it is not necessary for the polygonal mirror and the motor driving the polygonal mirror to be at a predetermined stable speed during the scanning operation.

Abstract: An image reading device for use in a digital copier, facsimile transceiver or similar image recording equipment and capable of changing a magnification change ratio. The device performs calculation for interpolation with image data representative of a document image and by using parameters adapted for the calculation. As a result, data representative of an image enlarged or reduced in the main scanning direction are written to a memory.

Abstract: A composite image forming apparatus includes a scanning part for obtaining image data for each dot by scanning a document in a main scanning direction and scanning the same in a sub scanning direction, a character generating part for generating character data indicating either a character or a numeric character, an image composition part for obtaining composite image data by combining the character data with the image data of the scanned document, an image forming part for carrying out an image forming process based on the composite image data so that a composite image is formed for each copy of the document, and a character setting control part for changing the respective character data each time a composite image is formed to make a copy of the document when an image forming process is repeatedly carried out with respect to the same document to make a plurality of copies.

Abstract: An image scanner for reading a document optically with a CCD image sensor or similar line image sensor, and electrically processing, e.g., amplifying and digitizing the resulting image signal. When an error occurs in the scanner, it can be located easily and rapidly.

Abstract: An image forming apparatus includes a scanner for scanning a plurality of document so that n images corresponding to the documents are obtained, n being an integer greater than 2, an image generating means for successively generating m number images different from each other, m being an integer greater than 2, an image composition circuit for combining an i-th image (i=1, 2 , . . . , and n) obtained by the scanner and a j-th number image (j=1, 2 , . . . , and m) with each other so as to output a composite image I.sub.ij, a printing mechanism for printing the composite image I.sub.ij on a recording sheet, and an output unit for outputting the recording sheet having the composite image I.sub.ij formed thereon.