Patent ID: 7778559

Claim:
A method of compensating, for position errors affecting toner density control in an image forming device, the method comprising: directing light towards a toner test surface and sensing resulting reflections; buffering density data corresponding to the sensed reflections during a predetermined test window, said test window spanning one or more toner test patterns disposed on the toner test surface; and compensating for mechanical and magnification position errors associated with the toner test patterns by processing the buffered density data to adjust a location of one or more data collection windows corresponding to the one or more toner test patterns; wherein the test window spans first and second boundary patterns that bound the one or more toner test patterns, and wherein compensating for toner test pattern position errors comprises: determining a time differential between the first and second boundary patterns based on the buffered density data; and compensating for the toner test pattern position errors by adjusting a location of the data collection windows relative to the first boundary pattern based on the determined time differential and a nominal expected time differential.