Liquid Crystal Light Path Control for Low-Scattering Viewing Angles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dimming films using polymer-dispersed liquid crystal (PDLC) struggle with achieving true black images due to light scattering, leading to image quality degradation and inability to utilize side light effectively.
Innovation Solution
A light path control device incorporating a substrate, first and second viewing angle control members with liquid crystal layers and light shielding patterns, allowing for refractive and side light control through adjustable refractive indices and electric field alignment of liquid crystal molecules, enabling private and share modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If liquid crystal dimming films are used to control light path, then viewing angle control is achieved, but light scattering occurs causing degradation of image quality and inability to achieve true black
Solution Approach 1:
The device is divided into multiple functional layers: a first viewing angle control member with liquid crystal, a second viewing angle control member with light shielding patterns, and a reflective layer. Each layer performs a specific function to collectively solve the light scattering problem while maintaining viewing angle control.
Solution Approach 2:
The light shielding patterns act as an intermediary element between the liquid crystal layer and the reflective layer. These patterns block scattered light from reaching the reflective layer, preventing it from returning to the viewer and causing image quality degradation.
2Adaptability or versatility
If light shielding patterns are added to control side light, then side viewing angle restriction is achieved, but device structure becomes more complex
Solution Approach 1:
The light shielding patterns are integrated directly into the second viewing angle control member, merging the light shielding function with the viewing angle control function in a single component rather than adding a separate element.
Solution Approach 2:
The second viewing angle control member serves multiple functions: it controls the viewing angle through its structural design and simultaneously provides light shielding through the integrated patterns, reducing the need for additional components.
3Illumination intensity
If liquid crystal molecules are aligned horizontally to transmit side light, then side light transmission is achieved, but refractive control is reduced
Solution Approach 1:
The liquid crystal molecules can dynamically change their alignment from horizontal to vertical based on applied voltage, allowing the device to switch between different optical modes and adapt to different viewing conditions.
Solution Approach 2:
The refractive index of the liquid crystal layer is changed by altering the molecular alignment through electric field application, thereby controlling the refraction of light passing through the device.
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 device reduces light scattering, maintains high brightness in the front direction, and allows for clear image visibility in both private and share modes without relying on scattering characteristics, enhancing image quality and brightness control.
Implementation Method 1
the liquid crystal layer may be configured, in a first mode, to have a first refractive index equal to that of the substrate and transmit a first side light incident through the substrate without refraction and, in a second mode, to have a second refractive index greater than that of the substrate and refract a second side light incident through the substrate
Implementation Method 2
The liquid crystal layer may include liquid crystal molecules, which may be aligned in a horizontal direction in the first mode and rotate, in the second mode, about a predetermined axis to be aligned in a vertical direction
Implementation Method 3
The first side light transmitted through the first viewing angle control member in the first mode may be restricted in lateral emission thereof by the light shielding patterns of the second viewing angle control member, restricting a side viewing angle
Implementation Method 4
The second viewing angle control member may include a pattern cover layer covering the light shielding patterns, the pattern cover layer having a refractive index greater than that of the outside of the light path control device. The second side light emitted to the top surface may be emitted toward the sides of the light path control device, opening a side viewing angle
Data Source
AI summary
A light path control device includes a substrate, a first viewing angle control member on the substrate comprising a first electrode, a second electrode, and a liquid crystal layer between the first electrode and the second electrode, and a second viewing angle control member on the first viewing angle control member comprising light shielding patterns patterned at predetermined intervals.