Patent attributes
A portable hand-held reader unit includes a photosensor array interiorly of the unit and optics for focusing an image of indicia of information contained on and occupying a predetermined area on a label exteriorly of the reader unit. The reader unit further includes a flashable light source such as a xenon flash tube which is disposed in a ring-like manner about the optical field of view of the reader unit. A marker source which in a preferred embodiment comprise four light sources such as photo diodes or laser diodes, for example, are peripherally disposed interiorly of the reader unit laterally adjacent the photosensor array or in another embodiment at the four corners of the photosensor array. Light emitted from the light sources is projected through the optics of the reader unit peripherally of the field of view of the reader unit as marker beams which impinge a surface toward which the reader unit may be pointed in marker spots peripherally of the predetermined area. When the impinging marker spots of light bracket the information indicia on the label and the xenon tube is flashed, the instantaneous illumination of the label transfers an image of the information indicia onto the photosensor array within the reader unit from where the information may be stored within memory or transferred by communication links to a central processor.
