Handheld Code Reader Having A Motion Sensor

• US 20090294541A1
• Filed: 12/21/2007
• Published: 12/03/2009
• Est. Priority Date: 12/21/2007
• Status: Active Grant

• Current Assignee: Cognex Corporation
• Original Assignee: Cognex Corporation
• Inventors: Nunnink, Laurens
• Granted Patent: US 7,857,218 B2
• Time in Patent Office: Days
• US Class Current: 235/470
• CPC Class Codes: G06K 7/10881 constructional details of hand-held scanners

Abstract

A method and apparatus for use with a handheld code reader that has an operating characteristic that can have at least first and second different states, the method for switching between the different states of the operating characteristic, the method comprising the steps of specifying a circumstance set including at least one of reader orientation and a threshold movement level for the reader, monitoring at least one of movement and orientation of the reader determining when the circumstance set occurs and changing the operating characteristic state when the circumstance set occurs, wherein the operating characteristic is one of an illumination mode and a code decoding algorithm.

Claims

1. A method for use with a handheld code reader that has an operating characteristic that can have at least first and second different states, the method for switching between the different states of the operating characteristic, the method comprising the steps of:

specifying a circumstance set including at least one of reader orientation and a threshold movement level for the reader;

monitoring at least one of movement and orientation of the reader;

determining when the circumstance set occurs; and

changing the operating characteristic state when the circumstance set occurs;

wherein the operating characteristic is one of an illumination mode and a code decoding algorithm.

2. The method of claim 1, wherein the circumstance set includes a threshold movement level of the reader and the handheld code reader includes a movement axis, the movement detected including movement with respect to the movement axis.

3. The method of claim 2 wherein the movement detected includes rotation substantially about the movement axis.

4. The method of claim 2 where the code reader includes an image obtaining component that has a field of view (FOV) centered on the movement axis and wherein the movement detected includes rotation substantially around the movement axis.

5. The method of claim 4 wherein the threshold movement level specifies rotation substantially around the movement axis through a threshold rotation angle.

6. The method of claim 5 wherein the threshold rotation angle is between 45 degrees and 180 degrees.

7. The method of claim 2 where the code reader includes an image obtaining component that has a field of view (FOV) centered on an FOV axis, the movement detected includes rotation substantially about the movement axis and the movement axis is substantially parallel to the FOV axis.

8. The method of claim 2 wherein the code reader movement is sensed by a motion sensor.

9. The method of claim 8 wherein the motion sensor is an accelerometer.

10. The method of claim 1 wherein the code reader includes a trigger member and the step of changing the operating characteristic state includes changing the state when the trigger member is activated and the detected reader movement exceeds the threshold movement level.

11. The method of claim 1 wherein the circumstance set includes a specific reader orientation and wherein the step of monitoring includes monitoring orientation.

12. The method of claim 11 wherein the circumstance set further includes activation of a reader trigger.

13. A method for use with a handheld code reader to select at least one reader operating characteristic, the method comprising the steps of:

detecting movement of the handheld code reader; and

determining, based on the movement of the reader, an optimum setting for the at least one reader operating characteristic;

wherein the at least one operating characteristic includes at least one of lens focus and exposure time.

14. The method of claim 13 wherein the at least one reader operating characteristic is lens focus and wherein the optimum setting for the at least one operating characteristic includes a lens focusing setting that is altered as the code reader is moved toward and away from a code to be read.

15. The method of claim 13 wherein the at least one reader operating characteristic is exposure time and wherein the optimum setting reduces the exposure time as the degree of movement increases.

16. The method of claim 13, wherein the sensing movement step further includes sensing the direction of movement of the reader.

17. The method of claim 16, further including the step of using the sensed direction of the reader movement to predict the direction in which the focus needs to be adjusted.

18. An apparatus for use with a handheld code reader that has an operating characteristic that can have at least first and second different states, the apparatus for switching between the different states of the operating characteristic, the apparatus comprising:

a sensor for detecting at least one of movement of the handheld code reader and orientation of the reader;

a comparator for comparing the at least one of detected reader movement and reader orientation to at least one of a threshold movement level and a specific orientation and determining at least one of when the detected reader movement exceeds the threshold movement level and the reader is oriented in the specific orientation; and

a characteristic selector for changing between the different states of the operating characteristic when the at least one of detected reader movement exceeds the threshold movement level and the reader is in the specific orientation;

wherein the operating characteristic is one of an illumination mode and a code decoding setting.

19. The apparatus of claim 18 wherein the handheld code reader includes a movement axis and wherein the sensor detects movement with respect to the movement axis.

20. The apparatus of claim 19 where the code reader includes an image obtaining component that has a field of view (FOV) centered on an FOV axis, the sensor detecting rotation substantially about the movement axis and the movement axis substantially parallel to the FOV axis.

21. The apparatus of claim 18 wherein the code reader movement is sensed by an accelerometer.

22. An apparatus for use with a handheld code reader to select at least one reader operating characteristic, the apparatus comprising:

a sensor for detecting movement of the handheld code reader;

a processor for determining, based on the movement of the reader, an optimum setting for the at least one reader operating characteristic; and

a characteristic controller for selecting optimum characteristic settings for the code reader as a function of the reader movement;

wherein the at least one operating characteristic includes at least one of lens focus and exposure time.

23. The apparatus of claim 22 wherein the at least one reader operating characteristic is exposure time and wherein the optimum setting reduces the exposure time as the degree of movement increases.

24. The apparatus of claim 22, wherein the sensor further senses the direction of movement of the reader and the processor determines the optimum setting as a function of the direction in which the reader is moving.

25. The apparatus of claim 24, further including the step of using the sensed direction of the reader movement to predict the direction in which lens focus is to be adjusted.