Barcode Orientation on LCD Screens to Resolve Moire Interference

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Barcode scanners struggle to correctly decode barcodes displayed on electronic device screens due to low reflectivity and Moire effects, which interfere with the detection of barcode dimensions.

Innovation Solution

A display device modifies barcodes by rotating parallel bars perpendicular to the pixel direction and adjusting their size to create a Moire fringe period larger than a threshold, ensuring the barcode is readable by scanners.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a standard barcode is displayed on an LCD screen, then the barcode can be shown on the display, but the barcode scanner cannot correctly decode the data due to low reflectivity and Moire effect

Engineering Contradiction:

Improvebarcode decoding accuracyVSAvoidMoire effect and low reflectivity

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the orientation parameter of the barcode by rotating it 90 degrees so that the bars are perpendicular to the pixel direction. This parameter change eliminates the Moire effect interference and improves reflectivity, allowing barcode scanners to correctly decode the displayed barcode data

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent converts the harmful Moire effect into a beneficial alignment by rotating the barcode 90 degrees. This transformation causes the barcode lines to align with the sub-pixel direction rather than conflicting with the pixel grid, thereby eliminating the Moire interference and improving scan readability

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

2Ease of operation

If the barcode dimensions are adjusted to fit the screen, then the barcode can be displayed on the electronic device, but the Moire effect interference increases making the barcode unreadable

Engineering Contradiction:

Improvebarcode display capabilityVSAvoidMoire effect interference

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent applies a 90-degree rotation transformation to the barcode dimensions, changing its orientation relative to the pixel grid. This parameter change allows the barcode to be displayed at appropriate sizes while the bars align with the sub-pixel direction, preventing Moire effect interference

Inventive Principle:

Principle #35Parameter changes

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

Enables barcode scanners to accurately read barcodes on electronic screens by mitigating Moire effects and ensuring sufficient contrast, facilitating reliable transactions in e-commerce.

Implementation Method 1

adjusting their size to create a Moire fringe period larger than a threshold, ensuring the barcode is readable by scanners

Methodology Applied

Scientific EffectMoire effect: Moiré Effect

Data Source

PatentUS10083384B2Display device for displaying barcode

Publication Date: 2018.09.25 AROLLTECH CO LTD(CN)

AI summary

A display device includes a screen. The screen is arranged to display a modifying barcode having a plurality of modifying parallel bars. The screen has a pixel direction and a sub-pixel direction different from the pixel direction. The plurality of modifying parallel bars of the modifying barcode are perpendicular or substantially perpendicular to the pixel direction.