Head-Tracking Multiview Display Using Segmented Backlight
Solution Overview
Problem
Passive displays, such as LCDs and EP displays, lack the ability to emit light, limiting their practical applications, and often require an external light source like backlights to function as active displays, which can lead to issues like 'jumps' or 'inverted views' when viewed at oblique angles.
Innovation Solution
A multiview display system that employs head-tracking technology to provide different sets of views based on the user's location, using a multibeam backlight with a diffraction grating to emit light beams at various principal angular directions, and a light valve array to modulate these beams, allowing for an increased angular field-of-view and reducing perception issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a passive display is coupled to an external light source to function as an active display, then the display can emit light and improve practical applications, but it may cause perception issues like jumps or inverted views when viewed at oblique angles
Solution Approach 1:
The display is divided into multiple independent light sources (first plurality of light sources and second plurality of light sources) that can be selectively activated based on viewing angle. This segmentation allows different regions of the display to emit light independently, enabling the system to provide stable views at various angles without the perception issues associated with single external backlight sources.
Solution Approach 2:
The system dynamically selects which set of light sources to activate based on the detected viewing angle. When a first viewing angle is detected, the first plurality of light sources is activated; when a second viewing angle is detected, the second plurality of light sources is activated. This dynamic adaptation ensures viewing stability across different angles while maintaining the light emission capability of passive displays.
2Adaptability or versatility
If multiple light sources are used to provide views at different angles, then the angular field-of-view is increased, but the device complexity increases
Solution Approach 1:
Each light source in the first and second pluralities is configured to provide multiple functions: they can emit light for normal viewing, provide elevated views at oblique angles, and contribute to the overall image display function. This multi-functionality allows the increased number of light sources to achieve broader angular coverage without proportionally increasing system complexity, as each component serves multiple purposes across different viewing conditions.
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 system enhances the angular field-of-view and reduces perception issues like 'jumps' or 'inverted views' by providing an augmented set of views that includes a secondary perspective, enabling a more comprehensive and stable 3D image representation without the need for external light sources.
Implementation Method 1
using a multibeam backlight with a diffraction grating to emit light beams at various principal angular directions
Implementation Method 2
a light valve array to modulate these beams, allowing for an increased angular field-of-view
Data Source
AI summary
A head-tracking multiview display and a head-tracking multiview display system selectively provide a primary set of views and a secondary view representing a perspective view of a scene that is angularly adjacent to the primary view set. The head-tracking multiview display includes a multibeam backlight configured to provide a plurality of light beams corresponding to different view directions of a multiview image and a light valve array configured to modulate the light beams to provide a plurality of views including the primary view set and the secondary view. The head-tracking multiview display system further includes a head tracker configured to determine a position of a user. At a first determined position the head-tracking multiview display is configured to provide the primary view set and at a second determined position the head-tracking multiview display being configured to provide the augmented view set.