Projection Image Calibration Using Projective Surface Parameters

Solution Overview

Problem

Existing projection systems face challenges in accurately calibrating parameters for external imaging devices due to changing baseline lengths, requiring manual user intervention and reducing convenience.

Innovation Solution

A method and system that utilizes imaging devices to capture images of a projection surface with projected patterns, acquiring projective transformation matrices to adjust projection images based on plane parameters, enabling automatic calibration without manual user intervention.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If external imaging devices are used instead of incorporated imaging units, then device versatility is improved, but parameter calibration complexity increases due to changing baseline lengths

Engineering Contradiction:

Improvedevice versatilityVSAvoidparameter calibration complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The projection device automatically performs calibration by capturing images with external imaging devices and computing projective transformation matrices without requiring manual user intervention. The system self-calibrates by using the captured images to determine geometric relationships and adjust projection parameters automatically.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The system dynamically adjusts calibration parameters based on the actual disposition position of external imaging devices. By computing projective transformation matrices from captured images, the system adapts to different baseline lengths and positions, transforming fixed parameters into variable parameters that automatically accommodate device placement variations.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If manual calibration is required for external imaging devices, then measurement precision can be maintained, but ease of operation deteriorates due to user intervention needs

Engineering Contradiction:

Improvecalibration precisionVSAvoidease of operation

Core Design Contradiction:

Measurement precisionVSEase of operation

Solution Approach 1:

The projection device automatically performs calibration by capturing images with external imaging devices and computing projective transformation matrices without requiring manual user intervention. The system self-calibrates by using the captured images to determine geometric relationships and adjust projection parameters automatically.

Inventive Principle:

Principle #25Self-service

3Productivity

If parameters are stored in advance in projectors, then calibration speed is improved, but adaptability worsens because parameters cannot accommodate changing baseline lengths of external imaging devices

Engineering Contradiction:

Improvecalibration speedVSAvoidadaptability to external imaging devices

Core Design Contradiction:

ProductivityVSAdaptability or versatility

Solution Approach 1:

The system performs preliminary image capture and automatic computation of projective transformation matrices before actual projection occurs. By pre-processing the calibration data from captured images, the system prepares transformation parameters that can be quickly applied during operation, achieving both speed and adaptability.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system dynamically adjusts calibration parameters based on the actual disposition position of external imaging devices. By computing projective transformation matrices from captured images, the system adapts to different baseline lengths and positions, transforming fixed parameters into variable parameters that automatically accommodate device placement variations.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS20260075174A1Projection image adjustment method, projection system, and non-transitory computer-readable storage medium storing information processing program

Publication Date: 2026.03.12 SEIKO EPSON CORP

AI summary

A projection image adjustment method includes: acquiring a first captured image corresponding to a first device including a first lens by capturing an image of a plane projection surface on which a first pattern image including at least four unit images is projected from a first projection device; acquiring a second captured image corresponding to a second device including a second lens by capturing an image of the projection surface; acquiring, based on the first captured image and the second captured image, a projective transformation matrix indicating transformation from a first coordinate system in a first device to a second coordinate system in a second device; and acquiring a plane parameter of the projection surface by using the projective transformation matrix.