Patent ID: 7357326

Claim:
An optical symbol scanner assembly for detecting and decoding a symbol lying on a surface of an article, the symbol comprising a pattern of fluorescent markings on a non-fluorescent surface, said fluorescent markings fluorescing at a second wavelength when stimulated by radiation at a first wavelength, the assembly comprising: a hand-held, compact, fixed mounted or mobile scanner device having a distal face on which is positioned light-generating means for producing illumination at said first wavelength to fall on said symbol, said first wavelength being in the visible spectrum, said light-generating means including at least one light emitting diode that emits light at said first wavelength, and focusing means for focusing an image of said symbol on an imager device positioned proximally thereof within said scanner device, said focusing means defining an optic axis; an optical filter in line with said focusing means for admitting illumination at said second wavelength and blocking illumination at said first wavelength; and a shroud mounted on the distal face of said scanner device, with an optical passageway having an optic axis aligned with the optic axis of said scanning device, and an illumination channel within the shroud for directing and guiding the light emitted by said diode, wherein said shroud is in the form of a hollow nosepiece having a open, wide proximal end fitting onto the distal face of said hand-held scanner device and a narrow distal end that is transparent to said radiation at said first and second wavelengths, and a tapered opaque shell that narrows in the direction towards the distal end, such that said radiation at said first wavelength impinges on said symbol and the scanner device views the symbol as radiation at said second wavelength as produced by said fluorescent markings.