BARCODE READER HAVING MULTIPLE SETS OF IMAGING OPTICS

• US 20150269403A1
• Filed: 03/20/2014
• Published: 09/24/2015
• Est. Priority Date: 03/20/2014
• Status: Active Grant

• Current Assignee: The Code Corporation (Brady Corporation)
• Original Assignee: The Code Corporation (Brady Corporation)
• Inventors: Lei, Ming, Powell, George
• Granted Patent: US 9,411,999 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06K 7/10792 Special measures in relation to the object to be scanned
• CPC Class Codes: G06K 7/10831 Arrangement of optical elements, e.g. lenses, mirrors, prisms optical elements per se G02B

Abstract

The present disclosure provides a barcode reader including a second set of imaging optics having a larger effective depth of field than a first set of imaging optics and requiring a larger amount of time to process a resulting image of a barcode into a decodable format. The barcode reader also includes a processor providing a decoded output based on an image acquired with the second set of imaging optics if an image acquired with the first set of imaging optics is not decodable.

Claims

1. A barcode reader, comprising:

at least one image sensor configured to capture an image of a barcode;

a first set of imaging optics having a first effective depth of field that produces a first image of the barcode on the at least one image sensor, wherein the first image requires a first amount of time to process into first decoder ready image data;

a second set of imaging optics having a second effective depth of field that produces a second image of the barcode on the at least one image sensor, wherein the second image requires a second amount of time to process into second decoder ready image data, and wherein the second effective depth of field is greater than the first effective depth of field and the second amount of time is greater than the first amount of time.

2. The barcode reader of claim 1, further comprising:

a processor configured to;

process the first image into the first decoder ready image data;

process the second image into the second decoder ready image data;

provide a decoded output based on the first decoder ready image data if the first image of the barcode therein is decodable; and

provide the decoded output based on the second decoder ready image data if the first image of the barcode in the first decoder ready image data is not decodable.

3. The barcode reader of claim 2, wherein the processor processes the second image into the second decoder ready image data only if the image of the barcode within the first decoder ready image data is not decodable.

4. The barcode reader of claim 1, wherein the second set of imaging optics includes a wavefront coding optic configured to cause a path length of the second set of imaging optics to vary spatially.

5. The barcode reader of claim 4, wherein the path length of the second set of imaging optics varies with respect to position along a plane transverse to an optical axis of the second set of imaging optics.

6. The barcode reader of claim 4, wherein processing the second image into the second decoder ready image data comprises removing an imaging effect induced by the wavefront coding optic.

7. The barcode reader of claim 6, wherein processing the second image into the second decoder ready image data comprises applying a filter to the second image to remove the imaging effect.

8. The barcode reader of claim 6, wherein processing the second image into the second decoder ready image data comprises deconvolving the second image to remove the imaging effect.

9. The barcode reader of claim 1, wherein the second set of imaging optics includes an adjustable lens having an object plane that is adjustable along an optical axis of the second set of imaging optics.

10. The barcode reader of claim 9, wherein processing the second image into the second decoder ready image data comprises varying a position of the object plane along the optical axis of the second set of imaging optics until a barcode image within the second decoder ready image data is decodable.

11. The barcode reader of claim 9, wherein the adjustable lens is a liquid lens.

12. The barcode reader of claim 9, wherein the adjustable lens includes an actuator configured to mechanically adjust the distance between a lens of the second set of imaging optics and the at least one image sensor along the optical axis of the second set of imaging optics.

13. A method of operating a barcode reader, the method comprising:

capturing a first image of a barcode on at least one image sensor using a first set of imaging optics having a first effective depth of field to produce the first image of the barcode on the at least one image sensor, the first image requiring a first amount of time to process into first decoder ready image data;

capturing a second image of the barcode on the at least one image sensor using a second set of imaging optics having a second effective depth of field to produce the second image of the barcode on the at least one image sensor, the second image requiring a second amount of time to process into decoder ready image data, wherein the second effective depth of field is greater than the first effective depth of field and the second amount of time is greater than the first amount of time.

14. The method of operating a barcode reader of claim 13, further comprising:

using a processor executing code stored on a non transient computer readable media to;

process the first image into the first decoder ready image data;

process the second image into the second decoder ready image data;

provide a decoded output based on the first decoder ready image data if the first image of the barcode therein is decodable; and

provide the decoded output based on the second decoder ready image data if the first image of the barcode in the first decoder ready image data is not decodable.

15. The method of operating a barcode reader of claim 14, wherein the processor processes the second image into the second decoder ready image data only if the first image of the barcode within the first decoder ready image data is not decodable.

16. The method of operating a barcode reader of claim 13, wherein:

the second set of imaging optics includes a wavefront coding optic configured to cause a path length of the second set of imaging optics to vary spatially; and

processing the second image into the second decoder ready image data comprises removing an imaging effect induced by the wavefront coding optic.

17. The barcode reader of claim 16, wherein processing the second image into the second decoder ready image data comprises applying a filter to the second image to remove the imaging effect.

18. The barcode reader of claim 16, wherein processing the second image into the second decoder ready image data comprises deconvolving the second image to remove the imaging effect.

19. The barcode reader of claim 13, wherein:

the second set of imaging optics includes an adjustable lens having an object plane that is adjustable along an optical axis of the second set of imaging optics; and

processing the second image into the second decoder ready image data comprises varying a position of the object plane along the optical axis of the second set of imaging optics until a barcode image within the second decoder ready image data is decodable.

20. The barcode reader of claim 19, wherein:

the adjustable lens is a liquid lens; and

varying a position of the object plane along the optical axis of the second set of imaging optics until a barcode image within the second decoder ready image data is decodable comprises adjusting a prescription curvature of the liquid lens.

21. The barcode reader of claim 19, wherein:

the adjustable lens includes an actuator configured to mechanically adjust the distance between a lens of the second set of imaging optics and the at least one image sensor along the optical axis of the second set of imaging optics; and

varying a position of the object plane along the optical axis of the second set of imaging optics until a barcode image within the second decoder ready image data is decodable comprises adjusting distance between the adjustable lens and the at least one image sensor.

22. A barcode reader, comprising:

at least one image sensor configured to capture an image of a barcode;

a first set of imaging optics which produces a first image of the barcode on the at least one image sensor, wherein the first image requires a first amount of time to process into first decoder ready image data;

a second set of imaging optics that produces a second image of the barcode on the at least one image sensor, wherein the second image requires a second amount of time to process into second decoder ready image data, and wherein the second amount of time is greater than the first amount of time; and

a processor configured to;

provide a decoded output based on the first decoder ready image data if the first image of the barcode therein is decodable; and

if the first decoder ready image data is not decodable;

provide a signal indicative of use of a second imaging system comprising the second set of imaging optics;

process the second image into the second decoder ready image data; and

provide the decoded output based on the second decoder ready image data.

23. The barcode reader of claim 22, wherein the processor further:

provides a good read signal, distinct from the signal indicative of use of the second imaging system, upon decoding of the first decoder ready image data if the first decoder ready image data is decodable.

24. The barcode reader of claim 23, wherein the processor further:

provides a good read signal, distinct from the signal indicative of use of the second imaging system, and after providing the signal indicative of use of the second imaging system, upon decoding of the second decoder ready image data.

25. The barcode reader of claim 24, where the good read signal is an audio signal of a first frequency tone and the signal indicative of use of the second imaging system is an audio signal of a second frequency tone distinct from the first frequency tone.

26. The barcode reader of claim 24, wherein the signal indicative of use of the second imaging system remains active until the earlier of:

i) producing decoded data from the second decoder ready image data and providing the good read signal;

or ii) determining that the second decoder ready image data is not decodable.