Infrared Image Non-Uniformity Correction with Compensation Arrays

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing infrared camera systems struggle with out-of-field radiation sensing, particularly due to temperature variations and structural elements within the camera, leading to non-uniformity in image quality.

Innovation Solution

A method and system for generating a compensation array using pixel value averages across a measurement array, adjusting these averages with parabolic functions to correct for out-of-field radiation, and verifying the correction array before application.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If existing infrared camera systems are used, then the camera can capture thermal images, but out-of-field radiation from structural elements causes non-uniformity in image quality

Engineering Contradiction:
Improveimage uniformityVSAvoidout-of-field radiation
Core Design Contradiction:
Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The system performs preliminary calibration to generate a compensation array that accounts for out-of-field radiation from structural elements before actual imaging. This pre-computed correction map is then applied to subsequent images to eliminate non-uniformity caused by thermal emission from camera housing and optical components.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

A compensation array serves as an intermediary data structure that mediates between the raw detector signals and the final corrected image. This intermediate correction map contains the spatial distribution of out-of-field radiation that is subtracted from the measured image data to recover the true thermal scene.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Manufacturing precision

If temperature variations in camera components are accounted for, then image uniformity improves, but the system requires complex temperature measurement and compensation mechanisms

Engineering Contradiction:
Improveimage uniformityVSAvoidtemperature compensation system
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The system performs self-calibration by using the detector array itself to measure the spatial distribution of out-of-field radiation from structural elements. No external temperature sensors or additional measurement equipment are required - the imaging detector directly captures and characterizes the thermal emission pattern, which is then used to correct future images.

Inventive Principle:
Principle #25Self-service

3Manufacturing precision

If flat field correction is applied to correct non-uniformity, then image quality improves, but the correction process requires knowledge of camera temperature conditions and component characteristics

Engineering Contradiction:
Improveimage uniformityVSAvoidtemperature condition requirements
Core Design Contradiction:
Manufacturing precisionVSLoss of information

Solution Approach 1:

The system performs preliminary calibration to generate a compensation array that encapsulates all temperature-dependent effects into a single correction map. This pre-computed array stores the spatial distribution of out-of-field radiation under various operating conditions, allowing rapid correction without requiring real-time temperature measurements or complex physical models during actual imaging.

Inventive Principle:
Principle #10Preliminary action

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

Enhances image uniformity by reducing the impact of out-of-field radiation, maintaining image quality without disrupting camera operation, and requiring no knowledge of camera temperature conditions.

Implementation Method 1

receiving a measured image comprising a measurement array of pixel values from a detector array of an infrared camera

Methodology Applied
Scientific EffectInfrared radiation detection: Photoelectric Effect

Data Source

PatentEP4626015A1Non-uniformity correction for infrared imaging
Publication Date: 2025.10.01 SEMICON DEVICES AN ELBIT SYSTEMSRAFAEL PARTNERSHIP IL
  • EP4626015A1 patent drawingFigure 1~2
  • EP4626015A1 patent drawingFigure 3A~4
  • EP4626015A1 patent drawingFigure 5

AI summary

An infrared image processing method including: receiving an image frame including a measurement array X of pixel values from a detector array of an infrared camera; calculating, from the measurement array: a row average vector r where calculating each element ri of the row average vector includes averaging corresponding elements of rows of the measurement pixel array; a column average vector c where calculating each element cj of the column average vector includes averaging corresponding elements of columns of the measurement pixel array; generating a correction array D by, for each element Dij of the correction array, summing a corresponding row average vector element ri and a corresponding column average vector element cj; and applying the measurement array X with the correction array D to provide a corrected measurement array.