Method of pulsing light emitting diodes for reading fluorescent indicia, data reader, and system
AssigneeEastman Kodak Company
InventorsThomas M. Stephany, Bryan D. Bernardi, Robert C. Bryant, David J. Nelson
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Abstract
A system includes a data reader and media bearing fluorescent indicia. A method includes the steps of: pulsing a light emitting diode at a forward current level above continuous use operating limits to produce pulsed radiation within an absorption spectrum of the fluorescent material and at a flux density sufficient to induce a fluorescent emission from the indicia; illuminating the indicia with the pulsed radiation to produce the fluorescent emission; and imaging the indicia on a radiation image sensor sensitive to radiation within an emission spectrum of the fluorescence.
Claims12
Method for reading an indicia of fluorescent material, said method comprising the steps of:
- pulsing a light emitting diode at a forward current level above continuous use operating limits to produce pulsed radiation, said radiation being within an absorption spectrum of said fluorescent material and at a flux density sufficient to induce a fluorescent emission from said indicia;
- illuminating said indicia with said pulsed radiation to produce said fluorescent emission;
- and
- imaging said indicia on a radiation image sensor sensitive to radiation within an emission spectrum of said fluorescence.
A data reader for reading indicia of fluorescent material, said data reader comprising:
- a body;
- an image sensor held by said body, said image sensor being sensitive to said indicia radiation images;
- a light emitting diode held by said body;
- a power unit disposed in said body, said power up it driving said light emitting diodes with a pulsed forward current at a level above continuous use operating limits for said light emitting diode.
Dependencies are inferred from the claim text.