Phosphor Sheet Edge Sealing for Moisture Protection

Solution Overview

Problem

Phosphor materials used in liquid crystal displays are prone to deterioration due to moisture vapor, especially at the edge portions of moisture vapor barrier films, leading to degradation despite existing protective measures.

Innovation Solution

A phosphor sheet is designed with a moisture vapor barrier film structure where the edge portions are sealed by a cover member, preventing moisture vapor entry and thus protecting the phosphor layer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If phosphor materials are used to convert light colors in liquid crystal displays, then color reproduction quality is improved, but phosphor deterioration occurs due to moisture vapor penetration from edge portions

Engineering Contradiction:

Improvecolor reproduction qualityVSAvoidphosphor durability

Core Design Contradiction:

Illumination intensityVSReliability

Solution Approach 1:

The moisture vapor barrier structure is segmented into multiple functional layers: a main moisture vapor barrier film covering the phosphor layer, and a cover member specifically sealing the edge portions. This segmentation allows targeted protection where moisture penetration is most critical (edges) while maintaining overall barrier effectiveness.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The cover member acts as an intermediary sealing element that bridges and seals the edge portions of the moisture vapor barrier film. This intermediary component prevents moisture vapor from penetrating through the edges, thereby protecting the phosphor layer without interfering with the light conversion function.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If existing protective measures are taken to block moisture vapor, then some protection is provided, but moisture vapor still enters from edge portions causing phosphor deterioration

Engineering Contradiction:

Improvephosphor protectionVSAvoidmoisture vapor penetration

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The protection strategy applies local quality by providing enhanced protection specifically at the edge portions through the cover member, while the main moisture vapor barrier film provides general protection. This localized enhancement at critical areas (edges) effectively addresses the specific problem of edge-related moisture penetration.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The cover member is positioned to preemptively seal the edge portions before moisture vapor can penetrate. This preliminary protective action prevents moisture vapor from reaching the phosphor layer at the vulnerable edge areas, countering the harmful effect before it occurs.

Inventive Principle:

Principle #9Preliminary anti-action

3Ease of manufacture

If a simplified structure is used for the phosphor sheet, then manufacturing ease is improved, but phosphor deterioration occurs due to insufficient moisture vapor blocking

Engineering Contradiction:

Improvestructure simplicityVSAvoidphosphor protection

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The moisture vapor barrier structure is segmented into multiple functional layers: a main moisture vapor barrier film covering the phosphor layer, and a cover member specifically sealing the edge portions. This segmentation allows targeted protection where moisture penetration is most critical (edges) while maintaining overall barrier effectiveness.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The cover member acts as an intermediary sealing element that bridges and seals the edge portions of the moisture vapor barrier film. This intermediary component prevents moisture vapor from penetrating through the edges, thereby protecting the phosphor layer without interfering with the light conversion function.

Inventive Principle:

Principle #24Intermediary (Mediator)

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

This configuration effectively prevents phosphor deterioration, maintaining the phosphor's integrity and performance even in high humidity environments, ensuring a longer lifespan and improved color consistency in liquid crystal displays.

Implementation Method 1

moisture vapor barrier films; and the first phosphor layer sandwiched between the moisture vapor barrier films

Methodology Applied

Scientific EffectMoisture vapor barrier: Adsorption

Implementation Method 2

each moisture vapor barrier film has an edge portion that is sealed by a cover member

Methodology Applied

Scientific EffectSealing: Physical Containment

Implementation Method 3

a phosphor-containing resin to convert blue color into white color

Methodology Applied

Scientific EffectPhosphorescence: Phosphorescence

Data Source

PatentUS9873832B2Phosphor sheet

Publication Date: 2018.01.23 DEXERIALS CORP

AI summary

Provided is a phosphor sheet that, despite its simplified structure, is capable of preventing deterioration in phosphors. In one of embodiments, the phosphor sheet includes moisture vapor barrier films 12 and 13 and a phosphor layer 11 that is sandwiched between the moisture vapor barrier films 12 and 13 and that includes a sulfide-based phosphor. Each of the moisture vapor barrier films 12 and 13 has an edge portion that is sealed by a cover member 14. The above structure prevents moisture vapor from entering the phosphor layer 11 from the edge portions of the moisture vapor barrier films 12 and 13, and accordingly, prevents deterioration in the phosphor(s) included in the phosphor layer 11.