Reflective Polarizer Light Recycling for Display Contrast
Solution Overview
Problem
Existing electronic display systems face challenges in efficiently adjusting light intensity and contrast, particularly due to complex calibration requirements and limitations in controlling LED zones, which affect the overall visibility and energy efficiency of the displays.
Innovation Solution
A display system utilizing a microcontroller to control light emitting elements, combined with reflective polarizers and a diffuser, dynamically adjusts light intensity and polarization to enhance visibility and reduce power consumption by recycling and reorienting light, allowing for local dimming and improved contrast through pixel-level control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If LED zones are used to control dimming and adjust visual properties, then the display can provide contrast level adjustments, but the calibration and control complexity increases
Solution Approach 1:
The patent extracts the light control function from complex LED zone calibration and replaces it with a simpler polarizer-based optical system. The polarizer is positioned to selectively block light from specific LED zones, providing contrast adjustment without requiring complex calibration and control of the LED zones themselves.
Solution Approach 2:
The patent introduces a polarizer as an intermediary optical element between the LED backlight and the display panel. This polarizer mediates the light control function by selectively blocking polarized light from specific zones, simplifying the control mechanism compared to direct LED zone control while achieving the desired contrast adjustment.
2Use of energy by moving object
If traditional light intensity adjustment methods are used, then the display can function, but energy efficiency is reduced due to light loss
Solution Approach 1:
The patent recovers light that would otherwise be lost by using a polarizer to redirect blocked light back through the display panel. The polarizer blocks light from specific zones and redirects it, allowing the light to be reused and reducing overall energy loss compared to traditional methods that simply dim LEDs without recovering the blocked light.
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 enhanced visibility and reduced power consumption by dynamically controlling light intensity and polarization, providing a more efficient and energy-saving display solution with improved contrast ratios and reduced halo zones.
Implementation Method 1
A reflective polarizer is positioned between the cross BEF collimator and the contrast panel, with the reflective polarizer oriented relative to an initial polarizer of the contrast panel. Polarization of light transmitted by the reflective polarizer matches that transmitted by the initial polarizer.
Implementation Method 2
The reflective polarizer is oriented relative to an initial polarizer of the contrast panel. Polarization of light transmitted by the reflective polarizer matches that transmitted by the initial polarizer. Collimated light propagating from the cross BEF collimator toward the contrast-enhancing panel is given a polarization bias by the reflective polarizer, which reflects incorrectly polarized light back toward the cross BEF collimator.
Implementation Method 3
an optical diffuser between the backlight and the first display unit. The optical diffuser is configured to scatter and redistribute light from the backlight to improve uniformity and reduce hotspots in the display.
Data Source
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AI summary
A display system includes a backlight configured to project light including a housing and one or more light emitting elements received in the housing and one or more reflective portions disposed on the housing. A first display unit is disposed proximate the backlight includes a liquid crystal layer and at least one reflective polarizer. A second display unit is disposed proximate the first display unit. The second display unit includes a TFT display layer and at least one linear polarizer. At least one microcontroller is in communication with one or more of the backlight, the first display unit and the second display unit. The at least one microcontroller executes instructions to adjust the liquid crystal layer of the first display unit between a first transmissive state and a second transmissive state.