Inkjet Print Head Nozzle Density Correction via Threshold Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing printing devices face challenges in correcting density variations caused by differences in printing characteristics between nozzles, leading to degradation in image quality due to changes in dot patterns.
Innovation Solution
A printing device and method that utilize a print head to eject ink dots of varying diameters, with a print-characteristic acquisition unit, distribution ratio determination unit, dot print position determination unit, and mask units to distribute ink dots based on print characteristic information, ensuring corrected density without degrading image quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If significant correction is made to correct density variations, then density correction is achieved, but visual recognition of difference in dot pattern occurs leading to degradation in image quality
Solution Approach 1:
The invention segments the correction process into multiple levels by introducing a threshold value. Corrections are applied selectively: when the difference in printing characteristics exceeds the threshold, correction is applied; when it is within the threshold, no correction is applied. This segmentation prevents over-correction that would cause visible dot pattern differences and grain visibility.
Solution Approach 2:
The invention changes the parameter of correction intensity by introducing a threshold value that controls when correction is applied. By adjusting this threshold parameter, the system achieves density correction while maintaining image quality, preventing the harmful effect of visible grain while still correcting significant density variations.
2Object-affected harmful factors
If maintenance in image quality is chosen, then image quality is preserved, but range that the printing characteristics can be corrected is limited
Solution Approach 1:
The invention changes the correction range parameter by introducing a threshold value that can be adjusted. This allows the system to extend the correction range to include significant density variations while maintaining image quality through selective correction only when necessary, rather than being limited to minor corrections only.
3Manufacturing precision
If correction is applied to density variations, then density uniformity is improved, but dot pattern consistency deteriorates
Solution Approach 1:
The invention segments the correction application based on the magnitude of density differences. By using a threshold value, it distinguishes between significant variations that require correction and minor variations that should be maintained as-is, thereby preserving dot pattern consistency while achieving density uniformity.
Solution Approach 2:
The invention changes the correction parameter threshold to balance density uniformity and dot pattern consistency. By adjusting this parameter, the system achieves sufficient density uniformity without causing noticeable changes in dot pattern, maintaining image quality while correcting density variations.
Data Source
AI summary
A printing device using a print head ejecting ink from a plurality of nozzles to print ink dots of a plurality of dot diameters, includes a print-characteristic acquisition unit obtaining print characteristic information on dot diameters of ink dots to be printed per each predetermined portion of the plurality of nozzles, a distribution ratio determination unit determining a distribution ratio for distributing image data to the predetermined portions of the plurality of nozzles based on the information, a dot print position determination unit quantizing the image data to determine a dot print position based on the image data and sizes and an array of thresholds; and a plurality of masks based on dot distribution order determined according to the distribution ratio, distributing printing of each of the ink dots of the plurality of dot diameters to the dot print position determined by the dot print position determination unit.