Head Mounted Display Pupil Tracking Beam Splitter Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional head-mounted displays with fixed beam splitters are inconvenient to use and cause eye fatigue due to the need for users to adjust their viewing direction to view projected images, as they cannot accommodate varying pupil positions effectively.
Innovation Solution
A head-mounted display system comprising a pico projector unit, eye image sensing unit, adjustment unit, and application-specific integrated circuit (ASIC) that captures eye image data and pupil position to adjust the imaging position of virtual images, allowing users to interact with virtual objects by adjusting the beam splitter or pico projector units based on pupil movement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the beam splitter position is fixed, then the device structure is simple, but the user must adjust viewing direction which causes inconvenience and eye fatigue
Solution Approach 1:
The beam splitter is transformed from a fixed static component to a dynamically adjustable component. The adjustment unit enables the beam splitter to move along the optical axis in response to pupil position detection, allowing the system to adapt to different viewing conditions automatically without requiring manual user adjustment.
Solution Approach 2:
The system implements a feedback loop where the eye image sensing unit continuously monitors pupil position, the ASIC processes this information to determine the required beam splitter adjustment, and the adjustment unit executes the positioning change. This closed-loop feedback mechanism ensures the beam splitter remains aligned with the user's pupil position throughout viewing.
2Manufacturing precision
If the beam splitter position is adjustable, then the imaging position can be aligned with pupil position, but the device complexity increases
Solution Approach 1:
The patent replaces complex mechanical positioning systems with an optomechanical solution. Instead of using complex motors or actuators to precisely position the beam splitter, the system uses a simplified adjustment unit that responds to optical feedback from the eye sensing unit, achieving precise alignment through optical-mechanical coupling rather than purely mechanical means.
3Adaptability or versatility
If the user adjusts viewing direction to view projected images, then the fixed beam splitter can function, but it causes eye fatigue and inconvenience
Solution Approach 1:
The beam splitter is transformed from a fixed static component to a dynamically adjustable component. The adjustment unit enables the beam splitter to move along the optical axis in response to pupil position detection, allowing the system to adapt to different viewing conditions automatically without requiring manual user adjustment.
Solution Approach 2:
The system performs self-adjustment based on automatic pupil position detection. The eye image sensing unit continuously monitors the user's pupil position, and the adjustment unit automatically repositions the beam splitter to maintain optimal alignment, eliminating the need for the user to manually adjust viewing direction or experience eye fatigue from repeated adjustments.
Data Source
AI summary
A head mounted display and a control method thereof are disclosed. The control method comprises following steps. An application processor controls a pico projector unit to project a virtual image having a virtual object located on a virtual image coordinate in a virtual image coordinate system. An eye image sensing unit captures an eye image data. A sensing apparatus senses a touch object to output a sensing data. An ASIC obtains a real image coordinate of the touch object in a real image coordinate system according to the sensing data. The ASIC obtains a pupil position according to the eye image data, and controls the adjustment unit to adjust an imaging position of the virtual image according to the pupil position. The ASIC determines whether the touch object touched the virtual object according to the pupil position, the real coordinate and the virtual coordinate.