Vision Testing System Using Head Impulse Tracking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for measuring eye movements, such as scleral search coil and video recording, are invasive or limited by high-speed camera costs, and lack accuracy for high-speed measurements in clinical settings, while conventional infrared technology faces challenges with electronic drift and low accuracy in darkness. Additionally, existing vestibulo-ocular reflex tests are not customizable and lack precision.
Innovation Solution
A system comprising a motion sensing device, a visual display device, and a data processing unit that tracks eye movements using both video-based and non-video-based sensors to measure head velocity and display visual objects during head impulse tests, allowing for customizable and accurate assessment of vestibulo-ocular reflex, with the ability to detect high-speed eye movements and differentiate signal noise from impulse displacement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If scleral search coil method is used to measure eye movements, then measurement precision is improved, but ease of operation deteriorates due to invasiveness and long preparation time
Solution Approach 1:
The patent replaces the mechanical scleral search coil method with a video-based optical system. The eye movement measurement device uses video cameras to track pupil movements and calculate eye position, eliminating the need for invasive contact lenses with embedded coils. This substitution maintains measurement precision while dramatically improving ease of operation and reducing preparation time.
2Ease of operation
If video recording method is used for clinical eye movement measurement, then ease of operation is improved, but measurement precision deteriorates due to camera speed limitations
Solution Approach 1:
The patent changes the key parameter of camera frame rate from conventional 250 Hz to high-speed 2000 Hz or greater. This parameter change enables the video system to accurately capture high-speed eye movements while maintaining the ease of operation and non-invasive nature of video recording. The high frame rate provides sufficient temporal resolution for measuring both low-speed and high-speed eye movements.
3Speed
If non-video based infrared technology is used, then speed of measurement is improved, but reliability deteriorates due to electronic drift and difficulty in darkness
Solution Approach 1:
The patent introduces an intermediary illumination system that provides controlled lighting to the subject's eyes during measurement. This intermediary light source enables the video cameras to capture reliable eye movement data without suffering from the electronic drift and darkness-related inaccuracies that plague non-video infrared technology. The illumination acts as a mediator between the measurement system and the subject's eyes.
4Ease of operation
If conventional vestibulo-ocular reflex tests are used, then ease of operation is improved, but adaptability deteriorates due to lack of customization
Solution Approach 1:
The patent implements a dynamic test protocol system that can be customized for individual subjects based on their specific needs and conditions. The system allows clinicians to adjust test parameters, visual stimulus characteristics, and measurement criteria to match each subject's requirements. This dynamic adaptability maintains ease of operation through automated control while providing the versatility to customize tests for different clinical scenarios and subject populations.
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 system provides a non-invasive, accurate, and customizable method for measuring both low-speed and high-speed eye movements, enabling precise testing of the vestibulo-ocular reflex with reduced preparation time and overcoming limitations of existing technologies.
Implementation Method 1
a motion sensing device configured to measure a velocity of a head of a subject
Implementation Method 2
video recording and analysis of pupil movements
Implementation Method 3
a non-video based infrared technology that can provide much higher speeds
Data Source
AI summary
A system for testing the vision of a subject is disclosed herein. The system includes a motion sensing device, the motion sensing device configured to measure a velocity of a head of a subject; a visual display device having an output screen, the visual display device configured to display one or more visual objects on the output screen so that the one or more visual objects are visible to the subject; and a data processing device, the data processing device operatively coupled to the motion sensing device and the visual display device, the data processing device being specially programmed to carry out the steps of the vision tests during which the subject's head undergoes an impulse displacement. A method for the testing the vision of a subject is also disclosed herein.