Inkjet Nozzle Correction Prioritizing Early Ejection Timing

The patent applies partial action by selecting only a subset of malfunctioning nozzles for correction based on their ejection timing. Specifically, nozzles that eject ink droplets earlier than adjacent nozzles are prioritized for correction, while late-ejection nozzles are excluded. This selective approach allows the correction process to complete within the short available time while still addressing the most critical malfunctions that would cause blank lines.

The patent implements preliminary action by determining the ejection order of nozzles before the actual printing process and pre-identifying which malfunctioning nozzles require correction. The control unit calculates the ejection timing relationships between nozzles and pre-determines the correction targets based on this preliminary analysis, allowing the correction process to proceed efficiently without time-consuming real-time calculations during printing.

The patent replaces the need for high-speed hardware with a software-based correction approach. Instead of using expensive high-speed hardware to process all malfunctioning nozzles simultaneously, the system uses the existing hardware combined with intelligent software algorithms that selectively correct only the critical early-ejection nozzles. This substitution reduces hardware requirements while maintaining acceptable processing speeds through optimized control logic.

The patent changes the parameter of correction scope from all malfunctioning nozzles to only early-ejection nozzles. By modifying this parameter based on ejection timing analysis, the system reduces the processing load on hardware, allowing standard hardware to suffice rather than requiring high-speed hardware, thus reducing apparatus cost while maintaining sufficient correction capability.