VR Refraction Measurement Using Virtual Background Targets
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for measuring refractive error and aberrations are imprecise, leading to significant variations in results between objective and subjective measurements, which affects the quality of life and productivity, and are prone to errors due to unstable test conditions and decreased contrast in background targets.
Innovation Solution
A device with a high-resolution background and detailed screen assembly that creates a controlled, immersive virtual environment for refractive error measurement, using adaptive optics and real-time data analysis to ensure precise and consistent results, independent of ambient light conditions, and featuring a portable VR headset with independent optical paths for each eye.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If an open field of view is used to replicate natural viewing conditions, then the test environment is more natural and comfortable, but the background light intensities and distances become difficult to control, leading to unstable test conditions
Solution Approach 1:
A virtual background target is introduced as an intermediary element between the subject and the physical environment. This virtual target, displayed through optical components (such as a beam splitter or augmented reality display), allows control over background characteristics without requiring control over the physical room environment. The virtual background can be dynamically adjusted to provide consistent lighting and distance parameters while maintaining natural viewing comfort.
2Reliability
If the background is made dark to avoid disturbing the virtual test, then test stability improves, but the advantages of having an instrument with an open field of view are lost
Solution Approach 1:
The virtual background target serves as a mediator that replaces the need for a dark physical background. By projecting a controlled virtual background through optical components, the system maintains an open field of view and natural lighting conditions in the physical environment while ensuring the virtual test elements remain clearly visible and undisturbed.
3Measurement precision
If a rail is adjusted for each subject and test, then measurement precision can be optimized, but the amount of error increases and practicality decreases
Solution Approach 1:
The system performs automatic refraction measurements without requiring manual adjustment of rails or other mechanical components for each subject. The optical components and software automatically adapt to individual subjects through automated alignment and measurement protocols, eliminating manual intervention while maintaining measurement precision.
Solution Approach 2:
Manual mechanical adjustment systems (rails) are replaced with automated optical and software-based systems. The virtual target and optical components can be dynamically adjusted through electronic control rather than mechanical movement, improving both precision and ease of operation.
4Measurement precision
If additional optics are added to ensure the target is optically at infinity, then far vision test accuracy improves, but device complexity increases
Solution Approach 1:
Complex mechanical optical adjustment systems are replaced with a virtual target displayed through controlled optical components. The virtual target can be optically positioned at infinity through electronic control of display and optical elements, avoiding the need for additional complex mechanical optics while maintaining measurement accuracy.
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 device provides precise and repeatable refractive error and aberration measurements, improving the accuracy of vision correction and reducing errors, while being compact and practical for use in various environments.
Implementation Method 1
an optical relay subsystem which generates at least two conjugated planes of the pupil of the subject for each eye. One plane to measure and one to manipulate the phase of the light of the detailed screen
Implementation Method 2
components which can manipulate the phase of the light... One plane to measure and one to manipulate the phase of the light of the detailed screen
Implementation Method 3
At least one laser source is present or an adapted diode to send the light into the eye and of which the reflected light is captured and used to determine the refraction and the aberrations of the eye
Implementation Method 4
It consists of optics which makes virtual images of the first and the second target. A beam splitter is in front of the first and the second eye guides the virtual images towards the eyes
Data Source
AI summary
A virtual reality instrument measures the refraction and aberrations of the eye in an automatic way, and includes a portable part which is a virtual reality headset foreseen of a detailed screen per eye and at least one background screen, both virtual. The detailed screen has a resolution multiple times the foveal resolution of the eye and the background screen has the resolution similar to the peripheral resolution of the eye. The virtual reality instrument also includes at least one pupil camera, a system to manipulate the phase of the light coming from the detailed screen, a wavefront sensor and light source to measure the wavefront using a wavelength of at least 400 nm.