HMD Pre-distortion Map for Pupil Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Head-mounted displays (HMDs) often struggle to accurately align lenses with a user's eyes, leading to discomfort, headaches, and double vision due to mismatches in inter-pupillary distance and chromatic aberrations, which result in improper image projection.
Innovation Solution
The implementation of a pre-distortion map that adjusts pixel placement based on the user's pupil position and lens characteristics, using eye tracking and ray tracing to dynamically compensate for optical misalignments and chromatic aberrations, ensuring images are projected correctly onto the user's field of view.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If fixed lens alignment is used in HMDs, then manufacturing is simplified, but image alignment accuracy with user's eyes deteriorates
Solution Approach 1:
The patent implements dynamic adjustment of lens alignment based on real-time detection of pupil position and inter-pupillary distance. The lens position is no longer fixed but can be dynamically adjusted to match individual user characteristics, resolving the contradiction between simplified manufacturing and accurate alignment.
Solution Approach 2:
The system changes the alignment parameters (lens position, display position) based on measured user-specific parameters such as inter-pupillary distance and pupil offset. This allows the same HMD to be accurately aligned for different users without requiring complex manufacturing variations.
2Device complexity
If standard inter-pupillary distance is used, then device design is simplified, but alignment accuracy for individual users deteriorates
Solution Approach 1:
The patent measures individual user parameters (inter-pupillary distance, pupil offset) and uses these measurements to adjust the optical parameters of the HMD. This maintains simple device design while achieving accurate alignment for each user through parameter adaptation.
Solution Approach 2:
The system incorporates feedback from eye tracking sensors that detect pupil position and inter-pupillary distance, using this feedback to dynamically adjust lens and display positions to achieve optimal alignment for each user.
3Device complexity
If chromatic aberration is not compensated, then processing is simplified, but image quality deteriorates
Solution Approach 1:
The patent applies pre-distortion to the displayed image based on predicted chromatic aberration effects. By pre-compensating for the expected optical distortions before the light passes through the lens, the system eliminates chromatic aberration without requiring complex post-processing or additional optical elements.
Data Source
AI summary
Display pre-distortion methods and apparatus for HMDs are disclosed. A disclosed example method includes determining a position of a pupil relative to a lens of the head-mounted display (HMD), determining, based on the determined position, a pre-distortion map for an image to be displayed on a display screen of the HMD, and displaying the image on the display screen of the HMD, wherein the image is modified by the pre-distortion map.