Point-of-Gaze Detection Using Personal Parameter Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing point-of-gaze detection techniques are limited by the assumption that the optical axis direction of the eyeball is aligned with the gaze direction, leading to inaccuracies in estimating the point-of-gaze due to individual differences between the two.
Innovation Solution
A device and method that estimate a corrected reflection point on the eyeball surface by accounting for the difference between the gaze direction and the optical axis direction of the eyeball, using a personal parameter to improve the accuracy of point-of-gaze detection in a surrounding environment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the optical axis direction of the eyeball is assumed to be aligned with the gaze direction, then the system installation is easy and equipment fitting is eliminated, but the accuracy of point-of-gaze estimation is limited due to individual differences
Solution Approach 1:
The patent introduces a personal parameter (rotation angle) that characterizes the individual difference between optical axis direction and gaze direction. By estimating this parameter from eyeball image characteristics and using it to rotate the coordinate system, the system accurately compensates for individual variations without requiring complex physical adjustments or equipment fitting.
2Measurement precision
If a personal parameter is introduced to correct the reflection point, then the point-of-gaze detection accuracy is improved, but the device complexity increases due to additional calculation steps
Solution Approach 1:
The patent replaces complex mechanical calibration systems with a computational approach. Instead of using complex hardware adjustments or multiple sensors, the system uses image processing to extract eyeball characteristics, estimates a rotation angle parameter, and applies coordinate transformation to achieve accurate point-of-gaze detection through software calculations.
3Measurement precision
If the reflection point is corrected using individual gaze direction differences, then the detection accuracy in varying depth environments is improved, but the difficulty of detecting and measuring increases
Solution Approach 1:
The patent performs preliminary estimation of the personal parameter (rotation angle) from the eyeball image characteristics before conducting the actual point-of-gaze detection. This pre-calculated parameter is then used to correct the reflection point in the coordinate system, enabling accurate depth-varying environment detection without requiring complex real-time adjustments during the measurement process.
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 solution enhances the accuracy of point-of-gaze detection, reducing errors in estimating gaze direction, especially in varying depth environments, and allows for non-wearing eye tracking applications.
Implementation Method 1
a reflection point estimating means for estimating a first reflection point, at which incoming light in an optical axis direction of an eyeball of the subject is reflected
Data Source
AI summary
A point-of-gaze detection device according to the present invention detects a point-of-gaze of a subject toward a surrounding environment. The device includes: an eyeball image obtaining means configured to obtain an eyeball image of the subject; a reflection point estimating means configured to estimate a first reflection point, at which incoming light in an optical axis direction of an eyeball of the subject is reflected, from the eyeball image; a corrected reflection point calculating means configured to calculate a corrected reflection point as a corrected first reflection point by correcting the first reflection point on the basis of a personal parameter indicative of a difference between a gaze direction of the subject and the optical axis direction of the eyeball; and a point-of-gaze detecting means configured to detect the point-of-gaze on the basis of light at the corrected reflection point and light in the surrounding environment.