Liquid Crystal Display Passivation Layer Thickness for Side Visibility

Solution Overview

Problem

Liquid crystal displays face challenges in maintaining transmittance and approximating side visibility to front visibility, with existing methods encountering difficulties in applying different voltages to sub-pixels and resulting in transmittance degradation.

Innovation Solution

A liquid crystal display design featuring a passivation layer with distinct thickness portions and strategically positioned sub-pixel electrodes, allowing the application of the same voltage to both sub-pixels to orient liquid crystal molecules with pre-tilt angles, thereby reducing transmittance degradation and enhancing side visibility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If different voltages are applied to the two sub-pixels to display different transmittances, then the side visibility of the display can be made to more closely approximate the front visibility, but there are difficulties in terms of processes and transmittance degradation occurs

Engineering Contradiction:

Improveside visibility approximationVSAvoidtransmittance degradation

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The passivation layer is designed with different thicknesses in different regions: a first thickness in the first sub-pixel region and a second thickness (greater than the first) in the second sub-pixel region. This local variation in thickness creates different capacitance values for each sub-pixel, allowing them to display different transmittances while both receiving the same voltage signal, thus improving side visibility without the complexity of separate voltage control

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention changes the physical parameter of the passivation layer thickness to create different capacitance characteristics in different sub-pixel regions. By controlling the thickness parameter (with a difference of 5000 Å to 10000 Å), the invention achieves different transmittance levels for each sub-pixel under the same voltage condition, resolving the contradiction between ease of operation and reliability

Inventive Principle:

Principle #35Parameter changes

2Ease of manufacture

If a uniform passivation layer is used for both sub-pixels, then the manufacturing process is simpler, but the side visibility cannot be approximated to front visibility

Engineering Contradiction:

Improveprocess simplicityVSAvoidside visibility

Core Design Contradiction:

Ease of manufactureVSEase of operation

Solution Approach 1:

The passivation layer is designed with different thicknesses in different regions: a first thickness in the first sub-pixel region and a second thickness (greater than the first) in the second sub-pixel region. This local variation in thickness creates different capacitance values for each sub-pixel, allowing them to display different transmittances while both receiving the same voltage signal, thus improving side visibility without the complexity of separate voltage control

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

Instead of making the entire passivation layer non-uniform (which would complicate manufacturing), the invention applies the thickness variation only to specific regions corresponding to different sub-pixels. The first portion and second portion are formed with different thicknesses selectively, achieving the desired functional differentiation while maintaining relative manufacturing simplicity through targeted rather than comprehensive modification

Inventive Principle:

Principle #16Partial or excessive action

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 design effectively prevents or reduces transmittance degradation while approximating side visibility to front visibility by using the same voltage for both sub-pixels, facilitating the orientation of liquid crystal molecules with pre-tilt angles, thus improving the display's performance.

Implementation Method 1

applying a voltage to the electric field generating electrodes to generate an electric field in the liquid crystal layer. The generated electric field determines the alignment of the liquid crystal molecules in the liquid crystal layer, and thereby determines the polarization of the incident light transmitted by the liquid crystal layer

Methodology Applied

Scientific EffectElectric field: Electric Field

Implementation Method 2

the polarization of the incident light transmitted by the liquid crystal layer

Methodology Applied

Scientific EffectPolarization: Polarisation

Implementation Method 3

A liquid crystal display design featuring a passivation layer with distinct thickness portions and strategically positioned sub-pixel electrodes, allowing the application of the same voltage to both sub-pixels to orient liquid crystal molecules with pre-tilt angles

Methodology Applied

Scientific EffectElectrostatic interaction: Electrostatics

Data Source

PatentUS9921423B2Liquid crystal display

Publication Date: 2018.03.20 SAMSUNG DISPLAY CO LTD

AI summary

A liquid crystal display according to an exemplary embodiment of the present system and method includes: a first substrate; a thin film transistor disposed on the first substrate; a passivation layer disposed on the thin film transistor and including a first portion and a second portion thicker than the first portion; a first sub-pixel electrode and a second sub-pixel electrode disposed on the passivation layer, spaced apart from each other, and positioned on one pixel region; a second substrate facing the first substrate; and a liquid crystal layer positioned between the first substrate and the second substrate, wherein the first sub-pixel electrode is disposed on the second portion of the passivation layer, and the second sub-pixel electrode is disposed on the first portion of the passivation layer.