Sheet Image Inspection With Conveyance-Speed Correction Data

Solution Overview

Problem

The variation in conveyance speed between different motors used for sheet conveyance in image reading systems can lead to elongation or shortening of images, reducing the accuracy of print quality inspection when comparing images formed on sheets.

Innovation Solution

An image forming system that includes a configuration to correct image data using a correction profile based on a test image, accounting for variations in conveyance speed, thereby reducing elongation and shortening, and improving inspection accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If different motors are used to drive the first and second conveyance units, then the system can use separate motor control for each conveyance unit, but the conveyance speed varies causing image elongation or shortening

Engineering Contradiction:

Improvemotor controlVSAvoidimage dimension

Core Design Contradiction:

Ease of operationVSManufacturing precision

Solution Approach 1:

The system changes the parameter of image data by applying correction data that compensates for conveyance speed variations. The correction data transforms the read image to match the original image dimensions, eliminating elongation or shortening caused by different motor speeds.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The system uses feedback by comparing the read image with the original image and generating correction data based on the difference. This correction data is then applied to subsequent readings to maintain consistent image dimensions despite conveyance speed variations.

Inventive Principle:

Principle #23Feedback

2Adaptability or versatility

If the conveyance speed of the sheet varies during image reading, then the reading process can adapt to speed changes, but the image becomes elongated or shortened reducing inspection accuracy

Engineering Contradiction:

Improveconveyance speed adaptationVSAvoidimage inspection accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The system changes the parameter of image data by applying correction data that compensates for conveyance speed variations. The correction data transforms the read image to match the original image dimensions, eliminating elongation or shortening caused by different motor speeds.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The system performs preliminary action by pre-calculating and storing correction data based on test images before actual inspection. This pre-computed correction data is then applied to correct images read during normal operation, ensuring accurate inspection regardless of conveyance speed variations.

Inventive Principle:

Principle #10Preliminary action

3Measurement precision

If correction data is generated using test images, then the inspection accuracy can be improved, but additional time and resources are required for correction data generation

Engineering Contradiction:

Improveinspection accuracyVSAvoidcorrection data generation time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The system performs preliminary action by pre-calculating and storing correction data based on test images before actual inspection. This pre-computed correction data is then applied to correct images read during normal operation, ensuring accurate inspection regardless of conveyance speed variations.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system uses self-service by automatically generating correction data using test images and applying it to correct subsequent readings without manual intervention. The system self-calibrates by comparing test image readings with original images and automatically creating the necessary correction data.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS20250284234A1Image forming system for inspecting quality of image formed on sheet and generating correction data to correct second image using the correction data

Publication Date: 2025.09.11 CANON KK

AI summary

An image forming system generates second image data representing a result of a reading unit reading an image on a sheet, corrects the second image data using correction data, the correction data being data obtained on the basis of image data obtained by the reading unit reading a predetermined image formed on the sheet by an image forming unit and image data corresponding to the predetermined image, and inspects, on the basis of the corrected second image data and a first image data, an image formed on the sheet on the basis of the first image data.