Eye Tracking Camera Layout for Precise Eye Rotation Center Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing VR, AR, and MR technologies face challenges in providing a comfortable and natural-feeling presentation of virtual image elements amidst real-world imagery due to the complexity of the human visual perception system.
Innovation Solution
A display system that uses eye tracking cameras and light emitters to estimate the center of curvature and rotation of the eye, allowing for the projection of virtual image content at varying depths and orientations based on corneal curvature and rotation data.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If eye tracking cameras and light emitters are used to estimate eye parameters, then measurement precision of eye center of rotation is improved, but device complexity increases
Solution Approach 1:
The patent uses light emitters as intermediary objects that reflect off the cornea to create glint patterns. These glints serve as mediators between the eye structure and the camera measurement system, enabling precise determination of the center of corneal curvature and center of rotation without directly measuring the eye's internal geometry. The light reflection pattern acts as an intermediary that translates complex eye parameters into measurable camera image data.
Solution Approach 2:
The patent replaces direct mechanical or contact-based eye measurement methods with an optical measurement system. Instead of using physical probes or complex mechanical apparatus to measure eye geometry, the system uses light reflection and camera imaging to non-invasively determine eye parameters. This substitution of optical methods for mechanical measurement reduces device complexity while maintaining or improving measurement precision.
2Measurement precision
If multiple eye tracking cameras are used to capture eye images from different locations, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent combines data from multiple eye tracking cameras to create a comprehensive measurement system. By merging the image data and measurement information from multiple camera locations, the system achieves more accurate determination of eye parameters than a single camera could provide. The processing electronics integrate the multi-camera data to calculate the center of corneal curvature and center of rotation with enhanced precision.
Solution Approach 2:
The patent transitions from two-dimensional eye tracking to three-dimensional eye parameter determination by adding multiple camera angles. The multiple cameras positioned at different locations provide depth information and spatial context that enables calculation of three-dimensional eye geometry, including the position of the center of rotation in 3D space. This dimensional enhancement improves measurement precision without requiring an excessive increase in device complexity.
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
Enhances the presentation of virtual image elements by accurately determining eye parameters, enabling realistic depth perception and interaction with real-world imagery.
Implementation Method 1
images of the eye captured by the first and second eye tracking cameras, glint reflections of the different light emitters observable in said images of the eye
Data Source
AI summary
A display system can include a head-mounted display configured to project light to an eye of a user to display virtual image content at different amounts of divergence and collimation. The display system can include an inward-facing imaging system possibly comprising a plurality of cameras that image the user's eye and glints for thereon and processing electronics that are in communication with the inward-facing imaging system and that are configured to obtain an estimate of a center of rotation of the user's eye using cornea data derived from the glint images. The display system may render virtual image content with a render camera positioned at the determined position of the center of rotation of said eye.