Optical Film Assembly for LCD Phase Delay Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional transmissive-type LCDs consume high power due to backlight assemblies, while reflective-type LCDs suffer from inconsistent display quality due to ambient light dependence, and both require high voltage supplies, leading to increased battery size and weight.
Innovation Solution
A liquid crystal display device with a liquid crystal layer that varies phase delay between λ/2+α and α based on applied voltage, coupled with a compensation film generating a compensation phase delay of −α, and an optical film assembly including a polarizer and phase shifting films to optimize display quality at lower power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a backlight assembly is used in transmissive-type LCD, then display brightness is improved, but power consumption increases dramatically
Solution Approach 1:
The patent employs a multi-mode LCD structure that can dynamically switch between transmissive mode (using backlight for bright displays) and reflective mode (using ambient light for power-saving operation). This dynamic switching capability allows the device to adapt to different viewing conditions and optimize power consumption based on environmental light levels.
Solution Approach 2:
The LCD device integrates both transmissive and reflective display modes within a single structure, making it universally adaptable to different lighting conditions. The display can function as a transmissive display when backlight is needed and as a reflective display when ambient light is sufficient, eliminating the need for separate display types.
2Use of energy by moving object
If reflective-type LCD is used to reduce power consumption, then power consumption decreases, but display quality becomes inconsistent due to ambient light dependence
Solution Approach 1:
The patent implements a multi-mode LCD that can dynamically switch between reflective and transmissive modes based on ambient light conditions. When ambient light is insufficient, the system switches to transmissive mode with backlight activation, ensuring consistent display quality across varying environmental conditions while maintaining power efficiency.
Solution Approach 2:
The patent incorporates a dimming function that can pre-activate the backlight or adjust display parameters before ambient light becomes insufficient, preventing display quality degradation. This preliminary action ensures smooth transition between modes and maintains consistent display performance.
3Power
If high voltage supply (4V or more) is used to drive LCD, then display performance is improved, but battery size and weight increase
Solution Approach 1:
The patent utilizes a multi-mode LCD structure that changes operational parameters between transmissive and reflective modes. In reflective mode, the LCD requires lower voltage operation, which directly reduces power consumption and allows for smaller, lighter battery designs while maintaining adequate display performance.
Solution Approach 2:
The patent implements periodic switching between transmissive and reflective modes based on usage conditions. By alternating between high-performance transmissive mode and power-efficient reflective mode, the system achieves average power consumption reduction, enabling smaller battery capacity while maintaining overall display 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 solution achieves consistent display quality at reduced power consumption, eliminating the need for high voltage supplies and minimizing battery size and weight, allowing for efficient operation in both transmissive and reflective modes.
Implementation Method 1
The liquid crystal layer generates a phase delay for light passing therethrough. The phase delay generated by the liquid crystal layer is varied between (λ/2+α) and a according to the voltage that is applied
Implementation Method 2
the compensation film generates a compensation phase delay of −α
Implementation Method 3
an optical film assembly including a polarizer and phase shifting films
Implementation Method 4
a first phase shifting film, and a second phase shifting film
Data Source
AI summary
An LCD apparatus including a first member, a second member, a liquid crystal layer and an optical film assembly is presented. A phase delay of the optical film assembly is about −α. In a normally white mode, the phase delay of the liquid crystal layer is about (λ/2)+α when no voltage is applied and about “α” when voltage is applied. In a normally black mode, the phase delay of the liquid crystal layer is about “α” when no voltage is applied, and about (λ/2)+α when voltage is applied. The phase delay between the liquid crystal layer when voltage is applied and the liquid crystal layer when voltage is not applied is about λ/2. “α” is a positive number. By manipulating the value of α, power consumption can be reduced. For example, the apparatus can be driven with a voltage below 2.5 V.