Optical focusing device

摘要: A hand held, omnidirectional symbology or bar code reader (10) images linear and two-dimensional codes (28; 34; 40; 52; 54) over relatively long working distances. The includes an imaging system including a focusing objective taking lens (92) photodetector (93) that forms image of in X Y directions simultaneously generates electrical signal representative the for subsequent downstream processing. Focusing is achieved via rotating disk (94) carries plurality optical shims (130) other light controlling surfaces different focus zones. through-the-lens (TTL) targeting provided to visually assist user positioning variety modalities assure will be captured within field view sharply imaged on when focused. Two artificial illumination are accommodate nearby may either specular partially diffuse more distant where reflection characteristics have less impact contrast. All reader's components housed ergonomically designed shell (12) reduce repetitive stress injuries while providing access interface protective cover various systems.