Non-contact Eye Movement Analysis Using Facial Comparison Target

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current methods for analyzing nystagmus, such as electronystagmogram and scleral search coil technique, are invasive, uncomfortable, and difficult to use in children, leading to inaccurate and unstable waveform measurements.

Innovation Solution

An eye movement analysis system that captures images of the subject's eyes and a comparison target on their face, allowing for accurate analysis of eye movement without the need for a Purkinje image or calibration, and is capable of functioning even when the distance between the image-capturing unit and the subject changes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If electronystagmogram is used to measure nystagmus, then measurement can be performed, but the subject experiences strong discomfort due to multiple electrodes attached to the face

Engineering Contradiction:

Improvenystagmus measurement capabilityVSAvoidsubject discomfort

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent replaces the mechanical/electrical electrode system with an optical imaging system. Instead of attaching electrodes to the face, the system uses a camera to capture eye movement by recording the movement of a marker or the eye itself, thereby eliminating the discomfort caused by multiple electrode attachments while maintaining measurement capability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent creates an optical copy or image of the eye movement rather than directly measuring electrical signals. By capturing the visual image of the eye or a marker attached to the eye, the system indirectly measures nystagmus through image processing, avoiding direct physical contact and discomfort

Inventive Principle:

Principle #26Copying

2Measurement precision

If scleral search coil technique is used to measure nystagmus, then measurement accuracy is highest, but the procedure is extremely invasive and requires a large space and large-scale magnetic field generator

Engineering Contradiction:

Improvewaveform analysis accuracyVSAvoidmagnetic field generator size

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces the complex magnetic field generator and coil system with a simple optical imaging system. Instead of requiring a large-scale magnetic field generator and contact lens with embedded electrodes, the system uses a camera to capture eye movement, dramatically reducing device complexity while maintaining measurement capability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent extracts the essential measurement function from the complex scleral search coil system. By removing the magnetic field generator, contact lens, and coil components, the system retains the core capability to measure eye movement through simplified optical imaging, thereby reducing invasiveness and device complexity

Inventive Principle:

Principle #2Taking out (Extraction)

3Ease of operation

If VNG with infrared camera is used to measure nystagmus, then non-contact measurement is achieved, but accuracy is limited and cannot be used for detailed waveform analysis

Engineering Contradiction:

Improvenon-contact measurementVSAvoidwaveform analysis accuracy

Core Design Contradiction:

Ease of operationVSMeasurement precision

Solution Approach 1:

The patent changes the measurement parameter from infrared Purkinje image (which has limited accuracy) to visible light imaging of the eye or marker. By using visible light and direct eye imaging instead of infrared reflection, the system maintains non-contact operation while significantly improving measurement precision and waveform analysis capability

Inventive Principle:

Principle #35Parameter changes

4Reliability

If conventional nystagmus analysis methods are used, then measurement can be performed, but children cannot be tested accurately due to invasive nature and discomfort

Engineering Contradiction:

Improvenystagmus analysis capabilityVSAvoidchild testing feasibility

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The patent replaces invasive mechanical/electrical measurement systems with a non-invasive optical imaging system. By using camera-based eye tracking instead of electrodes or coils, the system becomes suitable for children who would otherwise be unable to undergo testing due to discomfort and invasiveness, while maintaining reliable measurement capability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS12207875B2Eye movement analysis system, eye movement analysis method and program

Publication Date: 2025.01.28 TEIKYO UNIVERSITY

AI summary

An eye movement analysis system includes an image-capturing unit configured to capture a moving image including at least one of a right eye and a left eye of a subject and a comparison target on a surface of a face of the subject, and an analysis unit configured to analyze a movement of an eyeball of the at least one of the right eye and the left eye of the subject, based on a relationship between the at least one of the right eye and the left eye of the subject and the comparison target on the moving image captured by the image-capturing unit.