AR Display Brightness Adaptation via Ambient Light Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Augmented reality wearable devices with Digital Light Projectors face challenges in maintaining optimal brightness and reducing power consumption across varying ambient light conditions, leading to issues like image ghosting and color breakup.
Innovation Solution
The system dynamically adjusts the operation of the DLP projector by measuring ambient light and switching between 0% dark time and 50% dark time modes, while modifying pixel values to achieve desired brightness levels without introducing image ghosting or color breakup, using a combination of ambient light sensing, LED current control, and RGB composition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the DLP projector operates in 0% dark time mode to maximize brightness, then illumination intensity is improved, but image ghosting and color breakup occur
Solution Approach 1:
The system dynamically switches between 0% dark time mode (for maximum brightness in dark environments) and 50% dark time mode (for reduced brightness in bright environments). This dynamic adaptation allows the projector to optimize for either brightness or image quality based on ambient lighting conditions, resolving the contradiction between illumination intensity and image quality.
Solution Approach 2:
The system changes the dark time parameter (from 0% to 50%) based on ambient light sensor readings. By adjusting this operational parameter, the system can prevent image ghosting and color breakup when operating in bright environments while maintaining the ability to achieve maximum brightness when needed.
2Use of energy by moving object
If the DLP projector reduces LED current to save power, then use of energy is improved, but brightness output decreases
Solution Approach 1:
The system dynamically adjusts LED current based on ambient light conditions and operational mode. In 50% dark time mode with bright ambient light, the system uses reduced LED current to save power. In 0% dark time mode with dark ambient light, the system increases LED current to maintain brightness. This dynamic current adjustment resolves the contradiction between power consumption and brightness output.
Solution Approach 2:
The ambient light sensor automatically detects environmental lighting conditions and the system self-adjusts its power consumption and brightness output accordingly, eliminating the need for manual user intervention to balance power savings with brightness requirements.
3Adaptability or versatility
If the system adapts to varying ambient light conditions, then adaptability is improved, but device complexity increases
Solution Approach 1:
The ambient light sensor serves multiple functions: it detects ambient lighting conditions to determine operational mode (0% or 50% dark time), adjusts LED current levels, and triggers appropriate brightness compensation algorithms. This multi-functionality allows the system to achieve high adaptability without proportionally increasing device complexity.
Solution Approach 2:
The system uses feedback from the ambient light sensor to continuously monitor environmental conditions and automatically adjust projector operation. This closed-loop feedback mechanism enables seamless adaptation to varying ambient light while using a relatively simple sensor-processor-control architecture that doesn't excessively increase device complexity.
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
This approach allows the AR wearable device to adapt to a wide range of ambient light environments, maintaining desired brightness and power savings while preventing image quality issues, thus enhancing the user experience across different real-world settings.
Implementation Method 1
measuring ambient light and switching between 0% dark time and 50% dark time modes
Implementation Method 2
LED current control, and RGB composition
Data Source
AI summary
Disclosed are systems and methods for adaptively adjusting brightness of a wearable device projection system. The systems and methods perform operations comprising: causing projection elements of the AR wearable device to project an image; receiving a measure of ambient light from an ambient light sensor; adjusting one or more hardware parameters of the projection elements of the AR wearable device based on the measure of ambient light; modifying one or more color values of the image displayed by the projection elements of the AR wearable device based on the measure of ambient light; and projecting the image with the modified color values using the projection elements of the AR wearable device with the adjusted one or more hardware parameters.