Projection Image Correction Using Built-In Camera Alignment

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Solution Overview

Problem

Existing projection technologies struggle to quickly and accurately correct image distortion caused by uneven reflecting surfaces, particularly in short-throw and ultra-short-throw projectors, due to the need for direct alignment of auxiliary photographic devices, which affects correction speed and accuracy.

Innovation Solution

A method and apparatus that form a test image on a target reflecting surface, capture a template image within a preset capturing region, and use position correction values based on deviations from a standard image to correct the projected image, utilizing a projection device with a built-in camera or external devices like mobile phones to facilitate efficient and accurate image correction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a direct alignment method is used for capturing the projected image, then the correction accuracy may be improved, but the operation complexity and time consumption increase significantly

Engineering Contradiction:
Improvecorrection accuracyVSAvoidoperation complexity
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The projection device uses its own built-in camera to capture the projected image, eliminating the need for external auxiliary photographic devices. The device performs self-diagnosis and self-correction by comparing the captured image with the original projection, automatically determining distortion without requiring manual alignment operations.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The correction process is performed continuously during normal projection operation. The system continuously captures the projected image, compares it with the original, and applies real-time correction, eliminating the need for separate alignment and calibration steps that would interrupt the projection workflow.

Inventive Principle:
Principle #20Continuity of useful action

2Manufacturing precision

If traditional distortion correction methods are used, then comprehensive correction may be achieved, but the correction speed decreases due to multiple alignment steps

Engineering Contradiction:
Improvedistortion correction completenessVSAvoidcorrection speed
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The system pre-stores the original projection image before any distortion occurs. This original image serves as a reference for automatic comparison and correction, eliminating the need for manual alignment steps during the correction process. The correction is performed by directly comparing the current distorted image with the pre-stored original image.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system replaces manual mechanical alignment operations with automated image processing algorithms. The computer automatically compares images, calculates distortion, and applies correction without requiring physical adjustment of cameras or projectors, significantly speeding up the correction process while maintaining comprehensive distortion correction.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Adaptability or versatility

If auxiliary photographic devices are used for image correction, then correction functionality is achieved, but the device complexity and operational difficulty increase

Engineering Contradiction:
Improvecorrection functionalityVSAvoidsystem complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The system merges the camera function and image correction function into the projection device itself. The built-in camera captures the projected image, and the integrated processing unit performs distortion analysis and correction, eliminating the need for separate auxiliary photographic devices and reducing overall system complexity.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The projection device performs multiple functions: it projects images, captures images with its built-in camera, processes images for distortion analysis, and applies corrections. This multi-functionality eliminates the need for dedicated auxiliary devices, simplifying the system while maintaining comprehensive correction capabilities.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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

The method enables rapid and accurate correction of projected images by ensuring the template image is captured at an optimal angle, improving the efficiency and accuracy of distortion correction on uneven surfaces.

Implementation Method 1

A projector can achieve projection onto a specified reflecting surface as a projection surface for a user to view a projected image at different viewing angles based on the principle of diffuse reflection

Methodology Applied
Scientific EffectDiffuse reflection: Reflection

Data Source

PatentEP4664877A1Projection image correction method and apparatus, projection device, collection device, and medium
Publication Date: 2025.12.17 BEIJING ROBOROCK INNOVATION TECH CO LTD
  • EP4664877A1 patent drawingFigure 1~2
  • EP4664877A1 patent drawingFigure 3~4
  • EP4664877A1 patent drawingFigure 5~6

AI summary

Disclosed are a projection image correction method and apparatus, a projection device, a collection device, and a medium. The projection image correction method comprises: projecting to a target reflecting surface to form a test image, and obtaining a template image, wherein the template image is an image generated by collecting the test image when an edge of the test image is located in a preset collection area, the collection area is an area formed between a preset first collection box and a preset second collection box, and the second collection box surrounds the outer side of the first collection box; obtaining a position correction amount of a projection on the target reflecting surface on the basis of a deviation between the template image and a preset standard image; and on the basis of the position correction amount, correcting a target image to be projected by a projection device, to obtain a corrected image projected on the target reflecting surface.