Edge Detection for HUD Visibility Under High Luminance

Solution Overview

Problem

Head-up displays (HUDs) and helmet-mounted displays (HMDs) struggle to maintain visibility of image features under high background luminance conditions, as greyscale images can become too bright, obscuring the outside scene and reducing the pilot's ability to discriminate features effectively.

Innovation Solution

A method and system that acquire and process image data to identify feature boundaries, generating modified image data for real-time display as an outline image, with luminance equal to or greater than the real-world scene, to enhance visibility without obscuring the outside view. This involves using sensing means, such as cameras and thermal or radar sensors, and applying filters like convolution filters to maintain clarity and contrast.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If the display luminance is increased to improve feature visibility under high background luminance, then the visibility of image features is improved, but the outside scene becomes obscured and the total luminance exceeds comfortable viewing levels

Engineering Contradiction:

Improvedisplay luminanceVSAvoidscene obscuration

Core Design Contradiction:

Illumination intensityVSObject-affected harmful factors

Solution Approach 1:

The patent segments the image data processing into two distinct pathways: edge detection processing that extracts only boundary information, and full image processing that maintains complete visual information. By displaying only edge-detected features rather than complete images, the system provides critical feature information with minimal luminance output, avoiding scene obscuration while maintaining visibility under high background luminance conditions

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent extracts only the essential boundary information from the complete image data through edge detection algorithms. By taking out only the critical edge features and displaying them as outlined indicators rather than full grayscale images, the system minimizes the luminance required for display while preserving the ability to discern important features against high background luminance

Inventive Principle:

Principle #2Taking out (Extraction)

2Measurement precision

If the minimum grey level is increased to 20% of background luminance to ensure visibility, then feature discrimination is improved, but the peak display brightness must be increased to 20,000 ft-L which is too bright for comfortable viewing

Engineering Contradiction:

Improvefeature discriminationVSAvoidpeak display brightness

Core Design Contradiction:

Measurement precisionVSIllumination intensity

Solution Approach 1:

Instead of displaying full grayscale images that require high peak brightness to maintain the 100:1 luminance ratio, the patent inverts the approach by displaying only edge outlines with much lower luminance requirements. The edge detection approach allows feature discrimination to be achieved through contrast in edge presence rather than through grayscale luminance ratios, thereby inverting the traditional luminance-based visibility approach to an edge-based approach that requires far lower peak brightness

Inventive Principle:

Principle #13The other way round (Inversion)

3Loss of information

If a complete grayscale image is displayed to provide full dynamic range, then feature visibility is improved, but the display obscures the outside scene and reduces transparency

Engineering Contradiction:

Improvefeature visibilityVSAvoidscene transparency

Core Design Contradiction:

Loss of informationVSObject-affected harmful factors

Solution Approach 1:

The patent extracts only the essential boundary information from the complete image data through edge detection algorithms. By taking out only the critical edge features and displaying them as outlined indicators rather than full grayscale images, the system minimizes the luminance required for display while preserving the ability to discern important features against high background luminance

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent segments the image data processing into two distinct pathways: edge detection processing that extracts only boundary information, and full image processing that maintains complete visual information. By displaying only edge-detected features rather than complete images, the system provides critical feature information with minimal luminance output, avoiding scene obscuration while maintaining visibility under high background luminance conditions

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS8781246B2Image enhancement

Publication Date: 2014.07.15 BAE SYSTEMS PLC

AI summary

A method and system are disclosed for enhancing the visibility of features of an image. The method comprises the steps of acquiring image data corresponding to at least one image feature using sensing means; processing the image data to identify changes in adjacent data points corresponding to a boundary of the at least one image feature; and, generating modified image data corresponding to the processed image data.