Dynamic Image Scaling for Head-Mounted Display Eye Box Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Head-mounted displays (HMDs) face challenges in maintaining a viewable image area when the device moves relative to the wearer's eyes, leading to potential occlusion and increased eye strain due to limited eye box dimensions, which restricts the wearer's field of view and comfort during activities like jogging or walking.
Innovation Solution
The implementation of an HMD-tracking system that detects movement using accelerometers and gyroscopes, adjusting the image area within the display to remain visible by scaling it down or repositioning it dynamically, thereby maintaining a wider viewable area and accommodating relative movements of the HMD with respect to the wearer's eyes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If the image area is made larger to fill the display area, then the field of view is improved, but the image area becomes occluded when the HMD moves relative to the wearer's eyes
Solution Approach 1:
The patent applies dynamics by making the image area dynamically adjustable based on detected HMD movement. The controller modifies the size and/or position of the image area in real-time in response to acceleration and orientation data from sensors, allowing the system to adapt between maximizing field of view and maintaining visibility during movement.
2Area of stationary object
If the eye box dimensions are increased to accommodate movement, then the field of view is improved, but the size and weight of the optical system increases
Solution Approach 1:
The patent applies parameter changes by dynamically modifying the image area parameters (size and position) based on detected HMD movement. Instead of physically increasing the eye box dimensions, the system changes the display parameters to maintain visibility, avoiding the need for larger and heavier optical components.
3Object-affected harmful factors
If the image area is kept small to maintain visibility during movement, then eye strain is reduced, but the field of view is limited
Solution Approach 1:
The system dynamically adjusts the image area based on movement detection. During stationary periods, the image area can be larger to provide a wider field of view. During movement, the image area is reduced and repositioned to maintain visibility and reduce eye strain. This dynamic adaptation allows the system to optimize both field of view and comfort at different times.
Data Source
AI summary
A wearable computing system may include a head-mounted display (HMD) with a display configured to display images viewable at a viewing location. When aligned with an HMD wearer's line of sight, the entire display area of the display may be within the HMD wearer's field of view. The area within which an HMD wearer's eye can move and still view the entire display area is termed an “eye box.” However, if the HMD slips up or down, the display area may become obscured, such that the wearer can no longer see the entire image. By scaling or subsetting an image area within the display area, the effective eye box dimensions may increase. Further, in response to movements of the HMD with respect to the wearer, the image area can be adjusted to reduce effects such as vibration and slippage.