Indicia reading terminal including optical filter

摘要

Embodiments of the present invention comprise an indicia reading terminal that is operatively configured to decode visible and non-visible decodable indicia. The terminal can comprise an excitation illumination module for illuminating the decodable indicia with light that has a wavelength selected so as to permit the decodable indicia to emit light. The terminal can also comprise a filter module with an optical filter that has filter regions configured to pass certain wavelengths of light. The terminal can also comprise an image sensor module with an image sensor located so as to receive light emitted from the decodable indicia from the filter region.

主权项

1. An indicia reading terminal comprising:
an illumination source for casting light onto an indicia, the cast light having
a first wavelength in a non-visible spectrum that causes the indicia to emit light in a first visible wavelength, ora second wavelength different from the first wavelength, the second wavelength being in the non-visible spectrum that causes the indicia to emit light in a second visible wavelength different from the first visible wavelength; an optical filter comprising
a first filter region having a pass-band matching the first visible wavelength of the light emitted by the indicia, anda second filter region having a pass-band matching the second visible wavelength of the light emitted by the indicia; an image sensor for generating a signal corresponding to light incident on the image sensor, the image sensor having an optical axis on which the optical filter is aligned; wherein the terminal is configured for attempting to decode the indicia using the first wavelength and the first filter region, and if decoding is unsuccessful, attempting to decode the indicia by changing the illumination source to the second wavelength and changing the optical filter to the second filter region.