Display Light Attenuation via Movable Mirror and Dual Sources
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional augmented and mixed reality display systems face limitations in adjusting display brightness and contrast to match ambient light conditions, leading to potential discomfort and reduced image quality due to non-linear brightness control and instability at lower driving currents.
Innovation Solution
A display system incorporating multiple light sources and variable optical attenuators, such as liquid crystal attenuators, positioned in the optical path to control light transmission and adjust brightness and color balance dynamically, allowing for precise matching of display light to ambient conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single light source is used with conventional brightness control, then the device complexity is low, but the brightness control linearity and image quality deteriorate at lower driving currents
Solution Approach 1:
The single light source is segmented into multiple light sources (first light source and second light source), each operating at different driving currents. This segmentation allows the system to maintain optimal brightness control linearity across different brightness levels by selectively using appropriate light sources, thereby improving brightness control precision without significantly increasing overall device complexity.
Solution Approach 2:
The system changes the operating parameters (driving currents) of multiple light sources to achieve linear brightness control. By adjusting the driving currents of the first and second light sources independently and combining their outputs, the system maintains consistent brightness control linearity across the full brightness range, avoiding the non-linear behavior that occurs in conventional single-light-source systems at lower currents.
2Measurement precision
If multiple light sources with different driving currents are used, then the brightness control precision is improved, but the device complexity increases
Solution Approach 1:
Optical attenuators are introduced as intermediary components in the optical paths of both light sources. These attenuators provide precise control over the light output from each source, enabling fine-tuned brightness adjustment. The attenuators act as mediators that allow independent control of each light source's contribution to the final combined light, thereby improving brightness control precision while keeping the overall system architecture manageable.
Solution Approach 2:
The optical paths of the first and second light sources are merged to combine their light outputs. By merging the optical paths after individual attenuation control, the system achieves precise brightness control through the combined effect of two independently controlled light sources, while avoiding the complexity of entirely separate control systems. The merged optical path allows efficient use of optical components and simplifies the overall device structure.
3Speed
If display brightness is adjusted by changing light source driving current, then the response speed is fast, but the brightness control linearity deteriorates
Solution Approach 1:
The system dynamically selects and adjusts the operating state of multiple light sources based on the desired brightness level. By dynamically switching between and combining outputs from the first and second light sources with different driving currents, the system maintains linear brightness control across the entire brightness range while preserving fast response characteristics. The dynamic allocation of light source usage ensures optimal performance at all brightness levels.
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 achieves improved brightness control and color calibration, enhancing user experience by providing a comfortable and intuitive visual presentation that adapts to ambient light, while maintaining image quality across varying brightness levels.
Implementation Method 1
The attenuator may include a liquid crystal attenuator, which includes a vertically aligned nematic liquid crystal attenuator, or a parallel aligned nematic liquid crystal attenuator
Implementation Method 2
The movable mirror is movable to deflect the overlapping portion
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A display system (106) includes a first light source (108-1), a second light source (108-2), at least one movable mirror (124), and an attenuator (120). The first light source (108-1) is configured to provide a first light (112-1) in a first optical path. The second light source (108-2) is configured to provide a second light (112-2) in a second optical path. A portion of the second optical path overlaps the first optical path in an overlapping portion (118). The attenuator (120) is positioned in at least the first optical path and configured to attenuate at least the first light (112-1). The movable mirror (124) is movable to deflect the overlapping portion (118).