Printhead Registration via Optical Dash Center Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing inkjet printer systems face challenges in accurately registering printheads in situ due to noise sources and limitations in existing registration processes, which result in inefficiencies and inaccuracies in printing high-quality images.
Innovation Solution
A method and system for analyzing image data from a test pattern printed by multiple printheads, using optical detectors and a controller to identify the position of each printhead by determining dash centers and inkjet positions, allowing for precise cross-process direction alignment and correction of misalignments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional printhead registration processes are used, then registration can be performed, but measurement precision and manufacturing precision are insufficient due to noise sources and limitations in existing processes
Solution Approach 1:
The test pattern is divided into multiple rows of dashes, with each row containing dashes from different printheads. This segmentation allows individual analysis of each printhead's position by identifying dashes from specific printheads within each row, enabling precise measurement of each printhead's cross-process direction position independently.
Solution Approach 2:
The patent uses optical detectors to detect light reflected from the test pattern, utilizing optical properties to identify and analyze the printed dashes. By measuring reflected light characteristics, the system can precisely determine dash positions and thereby printhead positions, overcoming limitations of traditional registration methods.
2Productivity
If multiple printheads are used to increase printing capability, then productivity increases, but device complexity and difficulty of detecting and measuring positions increase
Solution Approach 1:
The test pattern structure segments information from multiple printheads into organized rows, where each row contains dashes from specific printheads. This segmentation simplifies the analysis process by allowing the system to process each printhead's position information independently through systematic identification of dashes within rows, rather than analyzing all dashes from all printheads simultaneously.
Solution Approach 2:
The system prints a test pattern, detects it with optical detectors, analyzes the detected image data to identify printhead positions, and uses this information to adjust printhead alignments. This closed-loop feedback process automates the registration procedure, reducing complexity despite multiple printheads.
3Measurement precision
If traditional test patterns are used, then registration can be performed, but measurement precision is insufficient due to noise sources in the printing environment
Solution Approach 1:
The test pattern uses distinct local characteristics for dashes printed by different inkjets, with each dash's position and properties providing localized information about its originating inkjet. This local quality enables precise identification of individual inkjet contributions even in the presence of noise, as each dash can be independently analyzed based on its specific positional and structural characteristics.
Solution Approach 2:
The system utilizes optical detection of reflected light from the test pattern to identify printed dashes. By analyzing optical properties of the reflected light, the system can distinguish actual printed dashes from noise sources, improving measurement precision in noisy printing environments.
4Loss of time
If existing registration methods are used, then registration can be completed, but loss of time and resource consumption are high
Solution Approach 1:
The system performs registration by analyzing a test pattern that can be printed and detected in a single operation, rather than requiring multiple iterative adjustments. The preliminary test pattern printing followed by immediate optical detection and analysis enables rapid determination of printhead positions, significantly reducing registration time compared to traditional methods.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables more efficient and accurate printhead registration, reducing time and resource consumption while improving the quality of printed images by effectively identifying and correcting registration errors within the printer.
Implementation Method 1
a plurality of optical detectors configured in the cross-process direction across the image receiving member... Each optical detector in the plurality of optical detectors is configured to detect light reflected from the image receiving member
Data Source
AI summary
A method of identifying positions of a plurality of printheads in a printer is described. The printer identifies the positions of each of the plurality of printheads with reference to image data of a printed test pattern. The printer calibrates one or more printheads using only a single test pattern to correct registration errors in the printheads.