PRINTER AND METHOD OF MEASURING DENSITY OF IMAGE FORMED ON PHOTOSENSITIVE UNIT

摘要

PURPOSE: A measuring method of image density on a photosensitive unit is provided to check the image density changes of a printer by measuring the image density on a photosensitive unit. CONSTITUTION: A set test pattern image is formed on a photosensitive belt if a developing density checking mode is set(100). If inner test pattern image data are set to form a test pattern image of 10% in density on the photosensitive belt, a controller scans beam corresponding to the image data of 10% in density to the photosensitive belt by controlling a scanner. The electrostatic latent image of the formed test image is developed by a developer having a yellow developing solution. If the test image reaches a light receiving area of a detector, the detector detects the incident beam from the test image-formed area and outputs the color elements of the detected beam separately(110). The controller provides the yellow color data of the test image to a density calculator in the developing density checking mode. The density calculator balances sub-color elements from the main color elements of the yellow color and calculates the density of the test image through a lookup table(120). The controller decides the density capability of a printer by comparing the calculated density with set value. The result is used for adjusting the operating conditions of each unit.