Lens Defect Detection Using Patterned Substrate Moire Distortion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for evaluating display lenses in communication devices, such as cellular phones, are inefficient as they do not effectively detect optic defects until the lens is installed and the LCD is activated, leading to potential distortions and manufacturing delays.

Innovation Solution

A system and method using a substrate with a finely impressed pattern, such as a grid or geometric shapes, to visually inspect lenses for distortions before installation, where the pattern appears as a grey background without imperfections but shows moiré distortion if the lens is defective, allowing for pre-installation evaluation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If a lens is made clear to provide good visual interface, then visibility is improved, but defect detection becomes difficult until installation

Engineering Contradiction:
Improvevisual clarityVSAvoiddefect detection
Core Design Contradiction:
Illumination intensityVSDifficulty of detecting and measuring

Solution Approach 1:

A patterned substrate is introduced as an intermediary element between the lens and the observer. The substrate contains a regular pattern of lines or geometric shapes that serve as a reference for detecting optical defects. When placed behind the lens, any distortions in the perceived pattern indicate lens defects, enabling detection without compromising the lens's visual clarity.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If lens evaluation is performed after installation, then accurate defect detection is achieved, but manufacturing efficiency decreases

Engineering Contradiction:
Improvedefect detection accuracyVSAvoidmanufacturing efficiency
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The evaluation process is moved to the preliminary stage, before lens installation. The patterned substrate enables defect detection to be performed on the lens itself during manufacturing or quality control, rather than requiring installation and LCD activation. This preliminary evaluation prevents defective lenses from being installed, improving manufacturing efficiency while maintaining detection accuracy.

Inventive Principle:
Principle #10Preliminary action

3Difficulty of detecting and measuring

If a patterned substrate is placed behind the lens, then defect detection is enabled, but the system complexity increases

Engineering Contradiction:
Improvedefect detection capabilityVSAvoidevaluation system complexity
Core Design Contradiction:
Difficulty of detecting and measuringVSDevice complexity

Solution Approach 1:

The patterned substrate is designed as a simple, inexpensive, and disposable evaluation tool. It can be a printed pattern on paper, a temporary adhesive sheet, or a simple transparency. The substrate does not need to be a permanent or complex component of the device - it is used only during evaluation and then discarded or reused, minimizing the addition of permanent complexity to the system.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

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 the early detection of lens imperfections, preventing defective lenses from being installed and reducing manufacturing inefficiencies by allowing for the rejection of distorted lenses before they are used in devices.

Implementation Method 1

The pattern appears as a grey background without imperfections when viewed through the lens when no notable imperfection exists in the lens and appears to be a moire distortion pattern when viewed through the lens when the lens is defective

Methodology Applied
Scientific EffectMoiré effect: Moiré Effect

Data Source

PatentEP1887339B1System and method for evaluating a lens for an electronic device
Publication Date: 2010.01.20 BLACKBERRY LTD
  • EP1887339B1 patent drawingFigure 1
  • EP1887339B1 patent drawingFigure 2
  • EP1887339B1 patent drawingFigure 3

AI summary

The invention relates to a system, method and device for evaluating imperfections in a lens for a display for an electronic device. For the device, it comprises: a substrate; and a pattern imposed on the substrate. For the pattern, when the pattern is viewed through the lens, the pattern is noticeably distorted around an area where a defect is present in the lens. For the system, it comprises: an evaluation table for the lens, the table having a mounting area; and a substrate for mounting on the mounting area, the substrate having a pattern imposed thereon wherein when the pattern is viewed through the lens, the pattern is noticeably distorted around an area where a defect is present in the lens.