METHOD FOR PRINTING NARROW IMAGE CONTENT
Image content is printed on a receiver medium using a continuous inkjet printer with a linear printhead having a cross-track printhead width that is wider than the cross-track image width. The linear printhead is characterized to determine an image quality level as a function of cross-track position. A segment of the linear printhead is designated wherein the image quality level within the designated segment of the linear printhead is acceptable. The linear printhead is translated relative to the receiver medium such that the designated segment of the linear printhead is aligned with a region on the receiver medium where the image content is to be printed, and the image content is printed on the receiver medium using the designated segment of the linear printhead.
1 . A method for printing image content having a cross-track image width using a continuous inkjet printer with a linear printhead having an array of ink nozzles, comprising:
a) characterizing the linear printhead to determine an image quality level as a function of cross-track position, wherein the linear printhead has a cross-track printhead width that is wider than a cross-track image width of an image content to be printed;
b) designating a segment of the linear printhead having a cross-track segment width at least as large as the cross-track image width of the image content to be printed, wherein the image quality level within the designated segment of the linear printhead is acceptable;
c) translating the linear printhead relative to a receiver medium using a translation mechanism to align the designated segment of the linear printhead with a region on the receiver medium where the image content is to be printed; and
d) printing the image content on the receiver medium using the designated segment of the linear printhead.
2 . The method of claim 1 , wherein characterizing the linear printhead includes:
i) providing digital image data for a test target;
ii) printing the test target using the linear printhead;
iii) capturing a digital image of the printed test target; and
iv) automatically analyzing the captured digital image to determine the image quality level as a function of cross-track position.
3 . The method of claim 2 , wherein the test target includes a flatfield test pattern, and wherein the step of automatically analyzing the captured digital image includes determining a magnitude of local variations in the captured digital image, wherein the magnitude of local variations in the captured digital image correspond to a measurement of an image quality level in the captured digital image.
4 . The method of claim 2 , wherein the test target includes a plurality of lines, each printed with a single ink nozzle, and wherein the step of automatically analyzing the captured digital image includes detecting missing lines, misplaced lines or jagged lines.
5 . The method of claim 2 , wherein the test target includes barcode patterns at different cross-track positions, and wherein the step of automatically analyzing the captured digital image includes verifying that the barcode patterns can be accurately read to extract the encoded information.
6 . The method of claim 1 , wherein characterizing the linear printhead includes:
i) providing digital image data for a test target;
ii) printing the test target using the linear printhead;
iii) visually evaluating the printed test target to assess image quality level as a function of cross-track position; and
iv) using a user interface to enter information providing an indication the assessed image quality level as a function of cross-track position;
wherein the steps iii) and iv) are performed by a user.
7 . The method of claim 6 , wherein the printed test target includes a plurality of regions corresponding to different printhead segments, each printhead segment having an associated cross-track position, wherein step iii) includes identifying any printhead segments having an unacceptable image quality level, and wherein step iv) includes entering information providing an indication of the identified printhead segments having an unacceptable image quality level.
8 . The method of claim 6 , wherein the printed test target includes a plurality of regions corresponding to different printhead segments, each printhead segment having an associated cross-track position, wherein step iii) includes identifying a printhead segment having an acceptable image quality level, and wherein step iv) includes entering information providing an indication of the identified printhead segment having an acceptable image quality level.
9 . The method of claim 6 , wherein step iii) includes identifying any cross-track positions having an unacceptable image quality level, and wherein the user interface enables the user to enter information providing an indication of the identified cross-track positions having an unacceptable image quality level.
10 . The method of claim 1 , wherein the step of translating the linear printhead relative to the receiver medium includes translating the linear printhead.
11 . The method of claim 1 , wherein the step of translating the linear printhead relative to the receiver medium includes translating the receiver medium.
12 . The method of claim 1 , further including repeating steps a)-d) when it is determined that printed image content has an unacceptable image quality.
13 . The method of claim 12 , wherein the printed image content is determined to have an unacceptable image quality by a human operator viewing the printed image content.
14 . The method of claim 12 , wherein the printed image content is determined to have an unacceptable image quality by capturing a digital image of the printed image content and automatically analyzing the captured digital image.
15 . The method of claim 1 , further including repeating steps a)-d) at predefined time intervals.
16 . The method of claim 1 , wherein the translation mechanism is a leadscrew mechanism.
17 . A method for printing image content having a cross-track image width using a continuous inkjet printer with a linear printhead having an array of ink nozzles, comprising:
a) characterizing the linear printhead to determine an image quality level as a function of cross-track position, wherein the linear printhead has a cross-track printhead width that is wider than a cross-track image width of an image content to be printed;
b) designating a segment of the linear printhead having a cross-track segment width at least as large as the cross-track image width of the image content to be printed, wherein the image quality level within the designated segment of the linear printhead is acceptable; and
c) translating the linear printhead relative to a receiver medium using a translation mechanism to align the designated segment of the linear printhead with a region on the receiver medium where the image content is to be printed;
wherein the step of characterizing the linear printhead includes:
i) providing digital image data for a test target;
ii) printing the test target using the linear printhead;
iii) capturing a digital image of the printed test target; and
iv) automatically analyzing the captured digital image to determine the image quality level as a function of cross-track position; and
wherein the step of automatically analyzing the captured digital image includes determining a magnitude of local variations in the captured digital image, the magnitude of local variations in the captured digital image corresponding to a measurement of an image quality level in the captured digital image.