Redundant LCD Pixel Array with Switching Isolation for Driver Failures

Solution Overview

Problem

Existing LCD display systems in safety-critical applications face challenges in maintaining functionality under adverse conditions due to single-point failures, leading to potential loss of critical data, and existing redundancy solutions require two distinct displays that waste resources when used separately.

Innovation Solution

A redundant display system using two sets of row drivers and a column of switching elements that isolates the left and right portions of the pixel array in case of a malfunction, allowing the system to function as a single large display during normal operation and as two independent displays during failures, with the option to conserve energy by turning off the backlight on the failing side.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If two independent LCDs are constructed side-by-side or front-to-back for redundancy, then reliability is improved, but device complexity and resource waste increase

Engineering Contradiction:

Improvedisplay functionalityVSAvoiddisplay system structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The pixel array is divided into left and right portions that can be independently controlled. A column of switching elements is inserted between the left and right portions, allowing each side to be independently activated or deactivated. This segmentation enables the display to function as one large display during normal operation or as two independent displays during failure conditions, providing redundancy without requiring completely separate display systems.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The display system dynamically reconfigures its operational mode based on failure conditions. During normal operation, the switching elements connect the left and right portions to function as a single unified display. Upon detecting a driver malfunction, the system dynamically isolates the affected portion using the switching elements, allowing the remaining functional portion to continue displaying information. This dynamic reconfiguration provides adaptive redundancy.

Inventive Principle:

Principle #15Dynamics

2Reliability

If two independent LCDs are constructed for redundancy, then reliability is improved, but loss of substance increases due to resource waste

Engineering Contradiction:

Improvedisplay functionalityVSAvoiddisplay resources

Core Design Contradiction:

ReliabilityVSLoss of substance

Solution Approach 1:

A single pixel array serves multiple functions: it can operate as one large unified display during normal conditions, or split into two independent displays during failure conditions. The column of switching elements enables this multi-functionality by allowing the same physical display resources to be configured differently based on operational needs, eliminating the need for separate redundant display hardware.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The left and right portions of the pixel array are merged into a single unified display structure that shares common resources (substrate, liquid crystal material, column drivers, and switching elements). This merging allows the system to provide redundancy functionality while using fewer total resources compared to implementing two completely separate display systems.

Inventive Principle:

Principle #5Merging (Combining)

3Device complexity

If a single LCD is used without redundancy, then device complexity is reduced, but reliability deteriorates under adverse conditions

Engineering Contradiction:

Improvedisplay system structureVSAvoiddisplay functionality

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The pixel array is divided into left and right portions that can be independently controlled. A column of switching elements is inserted between the left and right portions, allowing each side to be independently activated or deactivated. This segmentation enables the display to function as one large display during normal operation or as two independent displays during failure conditions, providing redundancy without requiring completely separate display systems.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The display system dynamically reconfigures its operational mode based on failure conditions. During normal operation, the switching elements connect the left and right portions to function as a single unified display. Upon detecting a driver malfunction, the system dynamically isolates the affected portion using the switching elements, allowing the remaining functional portion to continue displaying information. This dynamic reconfiguration provides adaptive redundancy.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS11043176B2Redundant display systems and methods for use thereof in safety critical applications

Publication Date: 2021.06.22 INT DISPLAY CONSORTIUM

AI summary

A redundant display uses row and column drivers to control an active matrix of transistors arranged in a pixel array. Row drivers arranged on respective sides of the pixel array control the voltage across entire rows of the pixel array in tandem. One or more sets of column drivers control the voltage across columns of the pixel array. One or more columns of switching elements are disposed between left and right portions of the pixel array. During normal operation, the column of switching elements connects left row portions with right row portions, such that an image is displayed across the entire pixel array. Responsive to a malfunction of row drivers on one side of the pixel array, the column of switching elements isolates the left row portions from the right row portions, such that the image may be displayed only on the other side of the pixel array.