Claims
- 1. An optical reader for generating an outgoing light beam to illuminate an information symbol comprising regions of different light reflectivity, and for collecting an incoming light beam reflected from the symbol, the reader comprising:a source of the outgoing light beam; light collection optics for collecting the incoming light beam and for directing the incoming light beam to a multi-channel photodetector; the multi-channel photodetector comprising an array of more than one individual active optical sensing element, each said element having an output capable of providing an output signal representative of light impinging thereon; the output of each detection element being coupled to a respective channel for processing the output signal of a respective detection element.
- 2. An optical reader according to claim 1, wherein one of the active optical sensing elements is positioned around another of the active optical sensing elements.
- 3. An optical reader according to claim 2, wherein the outgoing light beam, light collection optics, and array of sensing elements are configured so that the output of a first group of the sensing elements corresponds to a spot of a first size passing across the information symbol, and so that the output of a second group of the sensing elements corresponds to a spot of second size, larger than said first size, passing across the information symbol.
- 4. An optical reader according to claim 3, wherein the array of sensing elements comprises a first and a second sensing element, and wherein the first sensing element is contained within the first group and the first and the second elements are contained within the second group.
- 5. An optical reader according to claim 4, wherein the first group contains only the first sensing element, and the second group contains only the first and second sensing elements.
- 6. A reader for reading printed indicia comprising a light source for illuminating an indicia and a light detector for detecting light reflected from the indicia wherein the detector comprises a first region and a second region for detecting reflected light at a first resolution level and a second resolution level respectively, a first channel being associated with the first region and a second channel being associated with the second region.
REFERENCE TO RELATED APPLICATIONS
This application is a divisional of Ser. No. 08/598,928, filed Feb. 9, 1996, which is a continuation-in-part of Ser. No. 08/314,519, filed Sep. 28, 1994, now U.S. Pat. No. 5,506,392, which was a division of Ser. No. 08/109,021, filed Aug. 19, 1993, now U.S. Pat. No. 5,352,922, which was a division of Ser. No. 07/735,573 filed Jul. 25, 1991, now U.S. Pat. No. 5,278,397.
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Continuation in Parts (1)
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Number |
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Parent |
08/314519 |
Sep 1994 |
US |
Child |
08/598928 |
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US |