Prism-Based Camera Field Alignment in Head-Mounted Displays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Head-mounted display devices face challenges in aligning the camera's field of view with the user's vision field due to the camera's placement on the lateral surface, leading to mismatched vision fields.
Innovation Solution
Incorporating a prism with reflection-transmission surfaces and a camera module where the lens is positioned to face the prism, utilizing polarization beam splitters and condenser lenses to align the camera's view with the user's vision field, allowing the camera to capture images within the user's field of view.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the camera is mounted at a lateral surface of an eye to photograph a sight viewed by a user, then the camera can be positioned on the head-mounted display device, but the vision field viewed by the user and the photographed scope captured by the camera cannot be matched
Solution Approach 1:
A beam splitter is introduced as an intermediary optical element between the user's eye and the camera. The beam splitter divides the light path, allowing the camera to capture the user's field of view through optical redirection while the user maintains normal vision. This mediator enables both the user and camera to share the same optical path without direct mechanical alignment
Solution Approach 2:
The camera is positioned in a different spatial dimension relative to the user's eye, using optical elements to project the field of view onto the camera sensor. Instead of requiring the camera to be at the exact same position as the eye, the system uses dimensional transformation through mirrors and beam splitters to map the 3D visual field onto the 2D camera sensor plane
2Measurement precision
If the camera is mounted at the front side of the user's eye, then the photographed scope can be aligned with the vision field, but the camera cannot be mounted at the optimal position on the head-mounted display device
Solution Approach 1:
The beam splitter serves as a mediator that decouples the camera's physical mounting position from the optical alignment requirement. The camera can be mounted at a convenient position on the head-mounted device while the beam splitter ensures the optical path aligns with the user's field of view, resolving the conflict between mounting ease and alignment precision
3Adaptability or versatility
If the camera is mounted on the lateral surface of the eye, then the camera can be positioned on the device, but the photographed scope and vision field cannot be matched
Solution Approach 1:
The beam splitter and mirror system acts as an adaptable intermediary that can accommodate various camera mounting positions. By adjusting the orientation and position of the optical elements, the system maintains field of view matching regardless of where the camera is mounted on the lateral surface, providing both placement flexibility and precision
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 solution effectively matches the camera's field of view with the user's vision field, enabling accurate image capture and display, enhancing the functionality of head-mounted display devices.
Implementation Method 1
a prism for changing a path of incident light and then emitting the incident light, the prism having therein a reflection-transmission surface for reflecting or transmitting the incident light
Implementation Method 2
a prism for changing a path of incident light and then emitting the incident light
Implementation Method 3
the first reflection-transmission surface may be a first polarization beam splitter that reflects or projects a light in response to a polarization component
Implementation Method 4
the second optical surface may be formed with a condenser lens
Data Source
AI summary
Disclosed is a head mounted display device, the head mounted display device according to an exemplary embodiment of the present invention may comprise: a prism for changing a path of incident light and then emitting the incident light, the prism having therein a reflection-transmission surface for reflecting or transmitting the incident light; and a camera module of which a lens is disposed in a direction that faces the prism.