Patent ID: 6160922
Filing Date: 2000-12-12
Classification: H04N

Abstract:
An image forming apparatus comprising:image reading means for reading a document located at a preselected position by optically scanning the document to thereby output an image signal;image processing means for transforming said image signal to an output image signal;image writing means for writing information on an image carrier in accordance with said output image signal; andimage forming means for forming an image on a recording medium with a developer;said image processing means or said image writing means including an image signal generating device for generating a plurality of patterns and an image signal transform table disposed in said image processing means for transforming said image signal output from said image reading means to said output image signal;wherein in a procedure for correcting said image signal transform table with reference data in response to an output signal of said image reading means reading image patterns formed by said image writing means and said image forming means on the basis of said plurality of patterns, data representative of a background of the recording medium is read, and said output signal of said image reading means reading image patterns is corrected on the basis of data representative of the background of the recording medium where the image patterns are absent.