Variable Luminance Laser Projector for Wearable Heads-Up Displays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wearable heads-up displays face challenges in adapting display luminance without compromising content quality, particularly in varying ambient light conditions, leading to issues with battery conservation and user comfort.
Innovation Solution
A laser projector system with variable luminance, incorporating a red, green, and blue laser diode, an infrared laser diode, a liquid crystal element, and a controller that modulates opacity based on ambient light and laser light luminance signals, allowing for adjustable luminance while maintaining content quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If display luminance is decreased to conserve battery power and accommodate low-light conditions, then energy efficiency and user comfort improve, but display content quality deteriorates
Solution Approach 1:
The patent applies local quality by using wavelength-selective attenuation through liquid crystal elements that differentially attenuate visible light versus infrared light. This allows the system to reduce visible display luminance for user comfort while preserving infrared light intensity for maintaining display content quality and functionality.
Solution Approach 2:
The system changes the optical parameters of the light path by modulating the opacity of liquid crystal elements in response to detected luminance levels. This dynamic parameter adjustment enables adaptive control of display brightness while maintaining content quality through selective wavelength attenuation.
2Illumination intensity
If display luminance is increased to improve visibility in bright ambient conditions, then display content quality improves, but user comfort deteriorates in darker conditions
Solution Approach 1:
The patent implements dynamics by enabling real-time adjustment of display luminance through controller-modulated liquid crystal elements. The system dynamically adapts to ambient lighting conditions and user preferences, transitioning between high and low luminance states to optimize both visibility and comfort across varying environments.
Solution Approach 2:
The system uses feedback from ambient light sensors and user input to automatically adjust display luminance. The controller receives luminance detection signals and modifies the opacity of liquid crystal elements accordingly, creating a closed-loop system that maintains optimal display brightness and user comfort.
3Adaptability or versatility
If a transparent display is used to maintain visibility of external environment, then adaptability improves, but control over display luminance becomes more difficult
Solution Approach 1:
The patent introduces liquid crystal elements as intermediary components in the optical path between the laser light source and the user's eye. These intermediaries provide precise control over light transmission and attenuation, enabling independent adjustment of display luminance while maintaining the transparency of the overall display system for environmental visibility.
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
Enables dynamic adjustment of display brightness to suit different ambient conditions, conserving battery power and ensuring user comfort by effectively attenuating luminance through a modulatable liquid crystal element, with greater attenuation for visible light than infrared light.
Implementation Method 1
a liquid crystal element positioned in an optical path of the laser light between the at least one laser diode and the at least one scan mirror; and a controller communicatively coupled to the liquid crystal element, wherein an opacity of the liquid crystal element is modulatable
Implementation Method 2
at least one laser diode to provide a laser light
Implementation Method 3
at least one laser diode to provide a laser light
Implementation Method 4
at least one scan mirror positioned to receive the laser light from the at least one laser diode and controllably orientable to redirect the laser light over a range of angles
Data Source
AI summary
Systems, devices, and methods for laser projectors with variable luminance that are well-suited for use in a wearable heads-up display (“WHUD”) are described. Such laser projectors include a laser light source(s) and a scan mirror(s) to generate an image in the field of view of a user, and a liquid crystal element between the light source(s) and the scan mirror(s) to adjust the luminance of the image. The liquid crystal element is on an optical path between the laser light source(s) and the scan mirror and is communicatively coupled to a controller that modulates an opacity of the liquid crystal element. The opacity of the liquid crystal element determines the luminance of the image and may be altered in response to different factors, such as ambient light. Particular applications of the laser projector systems, devices, and methods in a wearable heads-up display are described.