Light Guide Board with Silica Gel Buffer Layer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current light guide boards for portable electronic products are too thick, with pure silica gel boards having weak light guide performance and uniformity issues, while PC-based boards with silica gel coatings are hard and lack good key press handles, failing to meet modern product requirements.

Innovation Solution

A light guide board comprising a buffer layer and discrete light guide plates with injection-molded pressing points and light scattering portions, achieving a thinner design with uniform light guide and improved key press functionality through the use of a silica gel buffer layer and polycarbonate light guide plates with varying concave light scattering features.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a light guide board is formed by binding injection molded PC board with silica gel key board or by injection molding liquid silica gel with injection molded PC light guide board, then both light guide function and good key press handle are achieved, but the formed light guide board becomes too thick

Engineering Contradiction:
Improvekey press handleVSAvoidthickness of light guide board
Core Design Contradiction:
Ease of operationVSLength of stationary object

Solution Approach 1:

The light guide board is divided into separate functional layers: a PC light guide plate layer for light guidance and a silica gel buffer layer for key press handling. These layers are combined through injection molding where the silica gel is injected into a hollow containing portion of the PC board, creating a composite structure that provides both light guide function and good key press handle while reducing overall thickness compared to binding separate components.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The silica gel buffer layer is nested within the hollow containing portion of the PC light guide plate. The PC board is designed with a hollow containing portion that receives and holds the silica gel, creating a nested structure where one material is embedded within the other. This nested design allows the two materials to work together in a compact configuration, achieving both light guide and key press functions without excessive thickness.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Device complexity

If a light guide board is formed from pure silica gel, then the structure is simple, but the light guide performance is weak with dark light emitting area and non-uniform light distribution

Engineering Contradiction:
Improvestructure simplicityVSAvoidlight guide performance and uniformity
Core Design Contradiction:
Device complexityVSIllumination intensity

Solution Approach 1:

The invention uses a composite structure combining PC (polycarbonate) and silica gel materials. The PC light guide plate provides excellent light guide performance with uniform light distribution, while the silica gel buffer layer provides structural support and key press handling. This composite material approach allows each material to contribute its strengths, achieving both structural simplicity and superior light guide performance that neither material could achieve alone.

Inventive Principle:
Principle #40Composite materials

3Illumination intensity

If a PC sheet with thickness of 0.12mm is used and silica gel is coated on the back surface, then good light guide effect is achieved, but the PC sheet is harder and the material itself has great tension resulting in poor key press handle

Engineering Contradiction:
Improvelight guide effectVSAvoidkey press handle
Core Design Contradiction:
Illumination intensityVSEase of operation

Solution Approach 1:

The PC light guide plate is designed with a hollow containing portion that locally accommodates the silica gel buffer layer. This local modification allows the PC plate to maintain its thin profile (0.12mm) for good light guide effect while the hollow portion provides a compliant space that improves key press handling. The silica gel is strategically placed in the hollow containing portion to provide buffering without compromising the overall light guide performance of the thin PC structure.

Inventive Principle:
Principle #3Local quality

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 solution ensures uniform light emission and enhanced key press handling with a thinner profile, meeting current market demands for electronic products by integrating a silica gel buffer layer and polycarbonate light guide plates with strategically placed light scattering portions.

Implementation Method 1

a light scattering portion

Methodology Applied
Scientific EffectLight scattering: Scattering

Data Source

PatentEP2350713B1Light guide board and light guide key board
Publication Date: 2014.03.26 BYD CO LTD
  • EP2350713B1 patent drawingFigure 1~2

AI summary

A light guid board is provided,which comprises:a buffer layer (5), light guide plates (4) having a first surface formed on the buffer layer by injection molding, a second surface having injected pressing points (1) with buffer function,and a light scattering portion (3). The light guide board may have uniform light guiding ability,good handle,and it can be very thin. A light guide key board having the light guide board is also provided.