Liquid Crystal Dimming Device Dynamic Frequency Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid crystal optical modulation devices face challenges in achieving low power consumption while minimizing flicker, particularly at lower drive frequencies and voltages, which is essential for effective gradation control in polymer dispersed-type liquid crystal panels.
Innovation Solution
A control circuit is introduced between the transparent electrodes and the commercial power supply, utilizing AC/DC converters and a microcomputer to adjust the voltage and frequency of the alternating current power supplied to the liquid crystal panel, optimizing the drive frequency and voltage to reduce power consumption and prevent flicker.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the drive frequency and voltage are reduced to lower power consumption, then energy efficiency improves, but flicker becomes more noticeable and device performance deteriorates
Solution Approach 1:
The patent implements dynamic adjustment of drive frequency based on the liquid crystal panel's state and operating conditions. The control circuit varies the frequency within a range (e.g., 1-100 Hz) rather than using a fixed frequency, allowing optimization between power consumption and flicker suppression. This dynamic approach enables the system to operate at lower frequencies for energy savings while switching to higher frequencies when flicker becomes problematic.
Solution Approach 2:
The patent changes the drive frequency parameter adaptively to resolve the contradiction. By adjusting the frequency parameter within an optimized range and using pulse width modulation (PWM) techniques, the system achieves low power consumption during normal operation while preventing flicker through frequency variation. The control circuit monitors and adjusts this parameter in real-time based on panel response and operating conditions.
2Device complexity
If a simple switch control is used for the liquid crystal panel, then device complexity is reduced, but the ability to perform gradation control and optimize performance is limited
Solution Approach 1:
The patent employs pulse width modulation (PWM) which uses periodic on-off switching at varying duty cycles to achieve gradation control. Instead of using complex analog voltage control, the system applies periodic rectangular wave signals with different pulse widths to control the liquid crystal panel's transparency levels. This periodic action provides versatile gradation control while keeping the control circuit relatively simple and robust.
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 configuration allows for controlled optical modulation of the liquid crystal panel with lower power consumption while effectively suppressing the appearance of flicker, enhancing the performance and reliability of the device.
Implementation Method 1
liquid crystal molecules in the polymer dispersed liquid crystal 17 are aligned with their major axes in the direction orthogonal to the glass surface
Implementation Method 2
A voltage is applied to the polymer dispersed liquid crystal 17 between the transparent electrodes 13 and 14 to form an electric field
Implementation Method 3
utilizing AC/DC converters and a microcomputer to adjust the voltage and frequency of the alternating current power supplied to the liquid crystal panel
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
There is provided a liquid crystal optical modulation device that performs light control drive of a liquid crystal panel, the device including a control section (20) that switches and sets a frequency of a drive voltage in the form of a rectangular wave applied to the liquid crystal panel in accordance with a range of the drive voltage.