Liquid Crystal Polarization Modulator with Local Alignment Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing polarization modulation elements with liquid crystal cells face issues such as residual birefringence near the interface, leading to decreased intensity of the desired polarized light component and increased power consumption due to high voltage requirements, and potential cell shorting.
Innovation Solution
A polarization modulation device with a controller that applies varying voltages to liquid crystal cells with differing average alignment angles, specifically targeting the cell with the smallest difference from 45°, to reduce residual birefringence and overall voltage demand.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If high voltage is applied to liquid crystal cells to cause liquid crystal molecules near the interface to respond, then residual birefringence is reduced, but power consumption increases and cell shorting may occur
Solution Approach 1:
The patent applies different alignment angles to different liquid crystal cells in the array. Specifically, cells at different positions have different average alignment angles between their light incident-side and light emitting-side substrates. This local differentiation ensures that each cell has optimal alignment characteristics for its position, reducing residual birefringence without requiring uniformly high voltage across all cells, thereby lowering overall power consumption.
Solution Approach 2:
The patent changes the alignment angle parameter across different liquid crystal cells. By varying the average alignment angle (making it differ from 45° for at least one cell), the system optimizes the balance between residual birefringence reduction and voltage requirements. This parameter variation allows certain cells to operate at lower voltages while maintaining acceptable polarization modulation performance.
2Manufacturing precision
If high voltage is applied to liquid crystal cells to cause liquid crystal molecules near the interface to respond, then residual birefringence is reduced, but the risk of cell shorting increases
Solution Approach 1:
The patent applies different alignment angles to different liquid crystal cells in the array. Specifically, cells at different positions have different average alignment angles between their light incident-side and light emitting-side substrates. This local differentiation ensures that each cell has optimal alignment characteristics for its position, reducing residual birefringence without requiring uniformly high voltage across all cells, thereby lowering overall power consumption.
Solution Approach 2:
The patent changes the alignment angle parameter across different liquid crystal cells. By varying the average alignment angle (making it differ from 45° for at least one cell), the system optimizes the balance between residual birefringence reduction and voltage requirements. This parameter variation allows certain cells to operate at lower voltages while maintaining acceptable polarization modulation performance.
3Speed
If the cell thickness of liquid crystal cells is reduced to shorten response time, then response time is improved, but the intensity of the desired polarized light component decreases due to residual birefringence
Solution Approach 1:
The patent applies different alignment angles to different liquid crystal cells in the array. Specifically, cells at different positions have different average alignment angles between their light incident-side and light emitting-side substrates. This local differentiation ensures that each cell has optimal alignment characteristics for its position, reducing residual birefringence without requiring uniformly high voltage across all cells, thereby lowering overall power consumption.
Solution Approach 2:
The patent changes the alignment angle parameter across different liquid crystal cells. By varying the average alignment angle (making it differ from 45° for at least one cell), the system optimizes the balance between residual birefringence reduction and voltage requirements. This parameter variation allows certain cells to operate at lower voltages while maintaining acceptable polarization modulation performance.
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 achieves high-intensity emission of desired polarized light across a wide range of wavelengths with reduced voltage consumption and minimized residual birefringence effects.
Implementation Method 1
a liquid crystal layer sandwiched between the light incident-side substrate and the light emitting-side substrate
Implementation Method 2
the controller applies voltage to each of the plurality of liquid crystal cells to switch a polarization direction of emission light emitted from the polarization modulation element
Implementation Method 3
birefringence due to the liquid crystal molecules remains near the interface
Data Source
AI summary
A polarization modulation device includes a polarization modulation element including a plurality of liquid crystal cells, and a controller that applies voltage to each of the plurality of liquid crystal cells. In a case in which an average value of the angle of the alignment axis of the light incident-side substrate and the angle of the alignment axis of the light emitting-side substrate in each of the plurality of liquid crystal cells is defined as an average alignment angle, the controller applies a voltage that is higher than a voltage applied to the other liquid crystal cells to the liquid crystal cell for which the absolute value of the difference between 45° and the average alignment angle is smallest.