Alignment method and apparatus

• US 7,348,999 B1
• Filed: 06/29/2005
• Issued: 03/25/2008
• Est. Priority Date: 06/29/2005
• Status: Active Grant

• Current Assignee: Cognex Corporation
• Original Assignee: Glenn Steven Spitz
• Inventors: Spitz, Glenn Steven
• Primary Examiner(s): Jankus; Almis R.
• Application Number:
  US11/170,346
• Time in Patent Office: 1,000 Days
• Field of Search: 345/689, 345/650
• US Class Current: 345/689
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1456 determining the orientation of the optical code with respect to the reader and correcting therefore

Abstract

An alignment aiding method and apparatus enables an orienting and positioning of a data carrying 2-dimensional graphical symbol within a field of view of an imaging device. The desired orientation and position is indicated by a graphical alignment indicator. The graphical alignment indicator is displayed in a fixed position on a display device, while an image of the graphical symbol is also displayed, and preferably updated and refreshed at a suitable refresh rate to provide usable feedback. While being displayed, the graphical symbol may be moved, oriented, and positioned, thereby enabling a substantial aligning of the data carrying 2-dimensional graphical symbol with the graphical alignment indicator. This abstract is provided to comply with rules requiring an abstract, and is submitted with the intention that it will not be used to interpret or limit the scope and meaning of the claims.

Claims

1. An alignment method for orienting and positioning a data carrying 2-dimensional graphical symbol within a field of view of an imaging device, the method comprising the steps of:

a) displaying, upon a display device, an image of the data carrying 2-dimensional graphical symbol, which is located within the field of view of the imaging device, with the displaying of the image of the data carrying 2-dimensional graphical symbol involving a collecting and storing of digital image information; and

b) displaying, also upon the display device, a stationary graphical alignment indicator, which is displayed along with the image of the data carrying 2-dimensional graphical symbol, for aiding in substantially aligning the data carrying 2-dimensional graphical symbol with the graphical alignment indicator;

c) wherein the collecting, storing, and displaying of digital image information is repeated, enabling a repeated updating of the displayed image of the data carrying 2-dimensional graphical symbol, thereby providing feedback for moving the graphical symbol within the field of view of the imaging device for effecting the substantial aligning of the image of the graphical symbol and the graphical alignment indicator;

d) providing an additional step such that once the data carrying 2-dimensional graphical symbol is substantially aligned with the graphical alignment indicator, a processing of the digital image information results in a determining of a print quality of the data carrying 2-dimensional graphical symbol.

2. The alignment method as recited in claim 1, wherein the additional step providing for the processing of the digital image information, upon the substantial aligning of the graphical symbol and the graphical alignment indicator, is initiated by at least one of:

a) a manual input from an operator observing the substantial aligning; and

b) an automatically generated command produced as a result of processing and analyzing the digital image information and determining that the data carrying 2-dimensional graphical symbol is substantially aligned with the graphical alignment indicator.

3. The alignment method as recited in claim 1, wherein the determining of the print quality also results in at least one of:

a) displaying upon the display device the determined print quality;

b) recording the determined print quality for later recalling;

c) transmitting the determined print quality to a remote location; and

d) causing a printing of the determined print quality, producing a hard copy record thereof.

4. The alignment method as recited in claim 1, wherein the step of displaying the graphical alignment indicator is realized, at least in part, by one of:

a) altering the contents of a memory containing the stored digital image information, causing an effective overlaying of an image of the graphical alignment indicator upon the image of the graphical symbol contained within the digital image information;

b) loading an image of the graphical alignment indicator into one of a plurality of image planes, with the loaded image plane configured for displaying the graphical alignment indicator, while at least one other image plane containing the image of the data carrying 2-dimensional graphical symbol, is configured for displaying the data carrying 2-dimensional graphical symbol; and

c) writing the graphical alignment indicator into a plurality of memory locations, and configuring the plurality of memory locations written with the graphical alignment indicator as read only, such that the now read only memory locations are not subsequently written with other image information, as image information containing the data carrying 2-dimensional graphical symbol is written into the memory, thereby enabling the graphical alignment indicator to be loaded only once, for a current orientation and position.

5. The alignment method as recited in claim 4, including an additional step of selecting one of a plurality of available pre-defined graphical alignment indicators, with each available graphical alignment indicator differing by at least one of:

a) having an associated and unique orientation-position pair; and

b) having a unique shape for use with at least one specific type of data carrying 2-dimensional graphical symbol.

6. A method for aiding in the orienting and positioning of a data carrying 2-dimensional graphical symbol, located within a field of view of an imaging device, in order to place the data carrying 2-dimensional graphical symbol in at least one of a plurality of pre-defined orientation-position pairs, the method comprising the steps of:

a) displaying a graphical alignment indicator upon a display device, in a selected pre-defined orientation-position pair, selected from a plurality of the pre-defined orientation-position pairs, with the graphical alignment indicator displayed for indicating a currently desired orientation and position in which the data carrying 2-dimensional graphical symbol is to be placed within the field of view of the imaging device;

b) displaying repeatedly an image of the data carrying 2-dimensional graphical symbol upon the display device, for viewing along with the graphical alignment indicator; and

c) moving the data carrying 2-dimensional graphical symbol and substantially aligning the image of the data carrying 2-dimensional graphical symbol with the image of the graphical alignment indicator.

7. The method as recited in claim 6, wherein an additional step is provided such that once the data carrying 2-dimensional graphical symbol is substantially aligned with the graphical alignment indicator, digital image information is processed for determining a print quality of the data carrying 2-dimensional graphical symbol.

8. The method as recited in claim 7, wherein the additional step providing for the processing of the digital image information upon the substantial aligning of the image of the graphical symbol and the graphical alignment indicator is initiated by at least one of:

a) a manual input from an operator observing and confirming substantial aligning; and

b) an automatically generated command produced as a result of processing and analyzing the digital image information and determining that the data carrying 2-dimensional graphical symbol is substantially aligned with the graphical alignment indicator.

9. The method as recited in claim 8, wherein the step of including a determining of the print quality results in at least one of:

a) displaying upon the display device the determined print quality;

b) recording the determined print quality for later recalling;

c) transmitting the determined print quality to a remote location; and

d) causing a hardcopy printing of the determined print quality.

10. The method as recited in claim 6, wherein the step causing the displaying of the graphical alignment indicator, includes at least one of:

a) modifying the digital image information to introduce an image of the graphical alignment indicator to the digital image information containing the image of the data carrying 2-dimensional graphical symbol;

b) transferring the digital image information from a first memory to a second memory, and modifying the digital image information within the second memory to introduce the graphical alignment indicator; and

c) transferring an image of the graphical alignment indicator into a pre-selected image plane, with the pre-selected image plane employed to hold and display the image of the graphical alignment indicator.

11. A method for orienting and positioning a data carrying 2-dimensional graphical symbol within a field of view of an imaging device, the method comprising the steps of:

a) imaging the graphical symbol located within the field of view of the imaging device, with the imaging causing a storing of digital image information including the image of the graphical symbol;

b) modifying the stored digital image information, causing a graphical alignment indicator to be included with the stored image information; and

c) displaying the resulting stored and modified digital image information modified of step-b, now including the graphical alignment indicator, upon a display device for aiding in substantially aligning the data carrying 2-dimensional graphical symbol with the graphical alignment indicator.

12. The method as recited in claim 11, wherein the steps of imaging, modifying, and displaying the digital image information are repeated, causing a repeated displaying of the data carrying 2-dimensional graphical symbol, and thereby providing feedback for aligning the graphical symbol.

13. The method as recited in claim 12, wherein an additional step is included such that upon a substantial aligning of the graphical symbol and the graphical alignment indicator a processing is effected upon stored digital image information causing an evaluating of the print quality of the data carrying 2-dimensional graphical symbol, with the processing initiated by:

a) a manual input from an operator observing the substantial aligning; and

b) an automatically generated command produced as a result of processing and analyzing the digital image information and determining that the data carrying 2-dimensional graphical symbol has been substantially aligned with the graphical alignment indicator.