Inkjet Recording Head Voltage Correction for Density Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inkjet recording devices with multiple recording heads face challenges in maintaining consistent ink discharge amounts, leading to image quality degradation due to variations in ink discharge between heads, particularly at joints, which existing techniques fail to adequately address.
Innovation Solution
An inkjet recording device and method that adjust the voltage correction values for each recording head to ensure consistent ink discharge amounts across all heads, using a test image to calibrate and set voltage correction values based on ink discharge data, thereby maintaining ink discharge uniformity and reducing density unevenness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If ink discharge amounts are adjusted for some of recording heads by controlling drive operation based on image data density, then density variation can be reduced, but differences between ink discharge amounts are generated locally at joints in nozzles of the recording heads
Solution Approach 1:
The patent divides the recording heads into multiple groups and performs ink discharge amount adjustment separately for each group rather than uniformly for all heads. This segmentation allows independent optimization of drive waveforms for different recording head groups, preventing the generation of local differences at joints while maintaining overall density uniformity across the entire recording system.
2Stability of the object's composition
If density unevenness at joints in nozzles of recording heads is solved by controlling drive operation for each recording head, then density matching at joints can be achieved, but ink discharge amounts of the recording heads become unequal to one another
Solution Approach 1:
The patent employs feedback mechanisms where the actual ink discharge amounts and density values are measured and used to adjust the drive waveforms for each recording head group. By continuously monitoring and adjusting based on measured values, the system achieves both density continuity at joints and uniform ink discharge amounts across all recording heads, resolving the contradiction between these two requirements.
3Productivity
If multiple recording heads are used to increase recording speed, then productivity is improved, but variation in discharge amount among the recording heads occurs
Solution Approach 1:
The patent changes the drive waveform parameters (amplitude, pulse width, frequency) for each recording head group based on their individual characteristics and measured ink discharge amounts. By adjusting these parameters differently for different groups while maintaining coordinated operation, the system achieves both high recording speed with multiple heads and consistent ink discharge amounts across all heads, eliminating the trade-off between productivity and precision.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
Provided are an inkjet recording device and an ink-discharge adjustment method for an inkjet recording device that can more effectively suppress reductions in the image quality of images recorded by a long recording means that has a plurality of recording heads. According to the present invention, for each of a plurality of recording heads of a recording means, a setting means establishes settings for adjusting the amount of ink that is discharged by a plurality of nozzle groups that are at the recording heads. On the basis of ink-discharge-amount information for a discharge-amount distribution for ink that is discharged from the nozzle groups on the basis of image data, the setting means performs a first adjustment operation, wherein settings are established such that the variance in representative values for the amount of ink discharged from each nozzle group at the joints between the nozzle groups meets prescribed continuity conditions and such that representative values for the total amount of ink discharged by the plurality of recording heads meet prescribed discharge-amount conditions, and a second adjustment operation, wherein settings are adjusted so as to reduce the difference between maximum and minimum values for the amount of ink discharged by the plurality of recording heads.