Optical reader having multiple scanning assemblies with simultaneously decoded outputs

• US 5,992,744 A
• Filed: 02/18/1997
• Issued: 11/30/1999
• Est. Priority Date: 02/18/1997
• Status: Expired due to Term

• Current Assignee: Welch Allyn Incorporated
• Original Assignee: Welch Allyn Incorporated
• Inventors: Ehrhart, Michael A., Smith, George S.
• Primary Examiner(s): Hajec, Donald
• Assistant Examiner(s): St. Cyr, Daniel
• Application Number:
  US08/802,536
• Time in Patent Office: 1,015 Days
• Field of Search: 235/462.01, 235/462.07, 235/462.09, 235/462.1, 235/462.11, 235/462.24, 235/472.01, 235/470
• US Class Current: 235/462.11
• CPC Class Codes: G06K 7/10574 Multiple sources

Abstract

An apparatus and method for reading optically encoded symbols which are of types which are not known in advance and which have significantly different illumination and imaging requirements. The apparatus and method use at least two optical scanning assemblies which have different illumination systems, different spatial resolutions and at least partially overlapping depth of field. These optical scanning systems are so located with respect to one another that a target symbol may be read by both scanning assemblies without the apparatus being manually reconfigured or moved during the reading process.

Claims

1. In an optical reader for reading data optically encoded in a target symbol, said optical reader being of the type which has a read cycle that includes a scanning phase and a decoding phase, in combination:

a first, imaging scanning assembly for imaging said target symbol and generating a first set of image data;

a second, laser scanning assembly for scanning said target symbol and generating a second set of image data;

image storage means for storing image data generated by said first and second scanning assemblies;

decoding means for decoding image data stored in said image storage means; and

control means for controlling the operation of said first and second scanning assemblies, said image storage means and said decoding means, said control means including a stored program that causes both of said scanning assemblies to scan said target symbol during the scanning phase of said read cycle, and that causes said decoding means to attempt to decode said first and second sets of image data, substantially simultaneously, during the decoding phase of said read cycle.

2. The apparatus of claim 1, further including output means for outputting data decoded by said decoding means, in which said output means outputs data decoded by said decoding means only when data resulting from the decoding of said first set of image data matches data resulting from the decoding of said second set of image data.

3. The optical reader of claim 1 in which said stored program includes a 1D autodiscrimination program, for use by said decoding means when it decodes image data generated by said second scanning assembly, and a 1D/2D autodiscrimination program, for use by said decoding means when it decodes image data generated by said first scanning assembly.

4. The optical reader of claim 3 in which said optical reader further includes mode selecting means for enabling a user to direct that a selectable one of said scanning assemblies be de-activated during later occurring read cycles, and that, during such later occurring read cycles, the decoding means attempt to decode only image data generated by the scanning assembly which is not de-activated.

5. The optical reader of claim 4 in which said mode selecting means includes one of a manually and a menu selectable means for directing said mode selecting means to deactivate a selectable one of said scanning assemblies.

6. The optical reader of claim 1 in which said optical reader further includes mode selecting means for enabling a user to direct that a selectable one of said scanning assemblies be de-activated during later occurring read cycles, and that, during such later occurring read cycles, the decoding means attempt to decode only image data generated by the scanning assembly which is not de-activated.

7. The optical reader of claim 6 in which said mode selecting means includes one of a manually and a menu selectable means for directing said mode selecting means to deactivate a selectable one of said scanning assemblies.

8. The apparatus of claim 1 in which said stored program causes said second scanning assembly to scan said target symbol while said first scanning assembly is imaging said target symbol.

9. The optical reader of claim 1 in which said first and second scanning assemblies have respective first and second depths of field, and in which said scanning assemblies are so located with respect to one another that said first and second depths of field overlap one another over at least a substantial fraction of the depth of field of one of said scanning assemblies.

10. The optical reader of claim 1 further including at least one aiming pattern generating means for generating at least one aiming illumination pattern for use in positioning said optical reader so that said target symbol can be read by both of said scanning assemblies.