Patent ID: 7974544
Filing Date: 2011-07-05
Classification: G03G

Abstract:
1. An electrophotography apparatus comprising: a template matching circuit configured to determine an image region in an image to be recorded based on original image data from an upper-level controller; a pulse width modulation circuit configured to generate image data in which the image data is pulse-width modulated based on a result of the determination made in the template matching circuit; an exposing unit configured to perform exposure based on the image data modulated by the pulse width modulation circuit; a toner image carrier configured to carry a toner image based on an electrostatic latent image formed by the exposing unit; a testing patch forming unit configured to form a toner image of a testing patch on the toner image carrier; an attached toner amount measuring unit configured to measure an amount of toner attached in the testing patch toner image from a front edge to a rear edge thereof; a testing patch edge detecting unit configured to detect an edge portion of the testing patch toner image where the attached toner amount is greater than in other portions of the testing patch toner image; a template generating unit configured to generate, based on the edge portion detected by the testing patch edge detecting unit, two kinds of templates having different sizes by determining a number of pixels between a reference pixel position and each of upper, lower, left, and right edges; an edge pixel region calculating unit configured to perform template matching on the image data to be printed using the templates, wherein a smaller region determined by the larger template is subtracted from a larger region determined by the smaller template to calculate a difference region as an edge pixel region of the image data; and an exposure amount setting unit configured to set an exposure amount for an electrostatic latent image portion corresponding to the edge pixel region, wherein the exposure amount for the edge pixel region of the original image data is controlled based on the exposure amount set by the exposure amount setting unit.