Zebra Technologies Corporation
Method of differentiating between focus drift and a change in distance to target for variable focus lens

Abstract:

A method and apparatus for differentiating focus drift of an imaging system from position changes of an object of interest. The method includes obtaining an image of an object of interest and identifying a region of interest in the image, wherein the region of interest contains an indicia indicative of the object of interest. The processor determines an image quality of the image and analyzes the indicia and determines a pixel measurement of the indicia. The processor then compares the pixel measurement of the indicia to a reference pixel measurement. Based on the comparison, the processor determines that the image quality of the image results either from a difference in a distance of the object from the imaging system or from focusing drift of the imaging system.