Image Reading Apparatus Color Measurement Error Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current image reading apparatuses face challenges in accurately measuring color values due to errors caused by the viewing angle of the imaging unit, particularly for images with high color saturation, leading to inconsistent measurement results.
Innovation Solution
An image reading apparatus is designed with an imaging unit that measures color values in the CIELAB color space, a measurement unit that calculates color measurement errors based on the relative position to the optical axis, and an output unit that displays or stores this error information along with the measured color values, using a lookup table to account for errors related to viewing angles and saturation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If color measurement is performed using a conventional imaging unit, then the measurement process is simple, but measurement precision deteriorates due to viewing angle errors
Solution Approach 1:
The system calculates error information based on the relative position of the measured position with respect to the optical axis and feeds back correction values to adjust the color measurement results. This feedback mechanism compensates for viewing angle errors while maintaining the simplicity of the imaging process.
Solution Approach 2:
The system changes the parameter space by introducing error information that depends on the relative position from the optical axis. By transforming the measurement model to include position-dependent error parameters, the system corrects viewing angle effects without complicating the physical measurement process.
2Measurement precision
If error correction is added to improve color measurement accuracy, then measurement precision improves, but device complexity increases
Solution Approach 1:
The imaging unit itself performs the error correction by calculating error information based on its own optical axis position relative to the measured position. The system uses self-generated correction data without requiring external calibration equipment or complex additional hardware.
Solution Approach 2:
The system pre-calculates and stores error information tables that map relative positions to correction values. This preliminary preparation allows the system to quickly apply corrections during measurement without requiring complex real-time calculations or additional measurement steps.
3Area of stationary object
If measurement is performed at positions away from the optical axis, then coverage area increases, but measurement precision deteriorates due to larger viewing angles
Solution Approach 1:
The system applies different correction strategies for different regions based on their distance from the optical axis. By generating error information specific to each measured position's relative location, the system maintains high measurement precision across the entire coverage area while accounting for position-dependent viewing angle variations.
Data Source
AI summary
Provided is an image reading apparatus including an imaging unit that images light incident from a medium on which an image is formed, a measurement unit that measures a color value on an image, based on image data obtained by the imaging unit, in correspondence with a position on the image, a generation unit that generates error information indicating an error included in the color value according to the color value measured by the measurement unit and a relative position of the position on the image with respect to an optical axis of the imaging unit, and an output unit that outputs the error information generated by the generation unit and the measured color value.