Scanner Distortion Correction via Cross-Correlation Offset

Solution Overview

Problem

Existing methods for correcting sinusoidal distortion in scanning imaging systems, such as those using Optical-Electrical Variable Pixel Clock systems and calibration methods, are not flexible enough to handle drifting synchronization signals from resonant scanners, leading to new distortions and inefficiencies.

Innovation Solution

A method involving processors that divide raw data into forward and backward scan data, reverse the order of the backward data, determine an offset value through cross-correlation, and shift the forward data relative to the inverted backward data to produce corrected images, effectively compensating for sinusoidal motion distortions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If a resonant scanner is used to scan the object, then the scanning speed is improved, but the image quality deteriorates due to sinusoidal distortion

Engineering Contradiction:

Improvescanning speedVSAvoidimage quality

Core Design Contradiction:

SpeedVSManufacturing precision

Solution Approach 1:

The patent replaces complex hardware-based distortion correction systems (optical-electrical variable pixel clock systems, frame grabbers, lookup tables) with a software-based cross-correlation method that operates on raw scan data. This substitution eliminates the need for additional hardware components while achieving accurate sinusoidal distortion correction through computational analysis of forward and backward scan data relationships.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent dynamically determines offset values by analyzing the cross-correlation between forward and backward scan data, allowing the system to adapt to variations in scanner motion parameters. This parameter-based approach enables real-time compensation for sinusoidal distortion without requiring fixed calibration data or predetermined correction tables.

Inventive Principle:

Principle #35Parameter changes

2Manufacturing precision

If existing distortion correction methods are used, then the image quality is improved, but the system complexity increases

Engineering Contradiction:

Improveimage qualityVSAvoidsystem complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex hardware-based distortion correction systems (optical-electrical variable pixel clock systems, frame grabbers, lookup tables) with a software-based cross-correlation method that operates on raw scan data. This substitution eliminates the need for additional hardware components while achieving accurate sinusoidal distortion correction through computational analysis of forward and backward scan data relationships.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The system uses the scan data itself to determine the offset value through cross-correlation analysis, eliminating the need for external calibration procedures or predetermined correction parameters. The method is self-calibrating by deriving correction information directly from the relationship between forward and backward scan data.

Inventive Principle:

Principle #25Self-service

3Manufacturing precision

If a variable pixel clock system is used to correct distortion, then the image quality is improved, but the hardware cost increases

Engineering Contradiction:

Improveimage qualityVSAvoidhardware cost

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent replaces complex hardware-based distortion correction systems (optical-electrical variable pixel clock systems, frame grabbers, lookup tables) with a software-based cross-correlation method that operates on raw scan data. This substitution eliminates the need for additional hardware components while achieving accurate sinusoidal distortion correction through computational analysis of forward and backward scan data relationships.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS9485383B2Image based correction of distortion from a scanner

Publication Date: 2016.11.01 CANON KK

AI summary

System, method, and non-transitory computer readable medium encoded with instructions for imaging an object. Dividing raw data into forward scan data and backward scan data. Reversing the order of the backward scan data to produce inverted backward scan data. Determining an offset value that is associated with a maximum value of a first function based on the forward scan data and the inverted backward scan data. The forward scan data is shifted by the offset value relative to the inverted backward scan data. Producing a first image of the object that comprises the forward scan data interlaced with the inverted backward scan data. The forward scan data is shifted by the offset value relative to the inverted backward scan data.