Light Blocking Layer with Transparent Film for Keyboard Backlight
Solution Overview
Problem
Current backlight modules in electronic devices, such as laptops, suffer from light leakage at the peripheral areas due to the use of a white, non-transparent reflecting plate, which prevents light from illuminating connection ports and other areas, necessitating an additional light source and compromising the space configuration.
Innovation Solution
A light blocking layer with a transparent film and a reflecting layer is positioned on the light guiding plate, allowing light to pass laterally through the film and form a light emitting area at the peripheral, eliminating the need for an extra light source and optimizing space design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a white non-transparent reflecting plate is used to wrap the peripheral of the light guiding plate to prevent light leakage, then light leakage is prevented, but connection ports and peripheral areas cannot be illuminated
Solution Approach 1:
The light blocking layer is designed with different transparency characteristics in different regions: the first light blocking layer uses a transparent film that allows light to pass through laterally to illuminate connection ports, while the second light blocking layer uses an opaque material to block light and prevent leakage. This local differentiation of material properties resolves the contradiction between preventing light leakage and illuminating peripheral areas.
2Illumination intensity
If an extra light source is disposed inside the casing structure to illuminate connection ports, then connection ports can be illuminated, but the space configuration of the backlight module is compromised
Solution Approach 1:
The transparent film of the first light blocking layer serves multiple functions: it blocks light in the vertical direction to prevent leakage while simultaneously allowing light to pass through laterally to illuminate connection ports. This multi-functionality eliminates the need for an additional light source and maintains the original space configuration of the backlight module.
3Reliability
If adhesive layers are used to bind the light blocking layer to the bottom plate and light guiding plate, then the light blocking layer is securely fixed, but the manufacturing cost and structure thickness increase
Solution Approach 1:
The first and second light blocking layers are integrated into a single unified structure that performs both light blocking and light guiding functions. This merging eliminates the need for separate adhesive layers to bind the light blocking layer to both the bottom plate and light guiding plate, thereby reducing manufacturing cost and overall thickness while maintaining secure fixation.
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 solution enables efficient illumination of connection ports and other areas without additional light sources, enhancing the flexibility of the backlight module's space design and reducing manufacturing costs by eliminating the need for adhesive between the light blocking layer and the bottom plate.
Implementation Method 1
the material of the transparent film to enable the light emitting from the light guiding plate and entering the light blocking layer can pass through laterally
Implementation Method 2
a reflecting layer having flat shape on a side surface of the light guiding plate
Implementation Method 3
provide a light absorbing layer on an outer surface of the transparent film
Data Source
AI summary
A light emitting structure around a keyboard backlight module is disclosed to include a light guiding plate comprising a light source, a flat-shape reflecting layer disposed on one side of the light guiding plate, and a transparent film of a light blocking layer disposed on other side of the light guiding plate and comprising a light absorbing layer. A deflection portion is bending inwardly toward the reflecting layer and then extending outwardly to form a flat-shape positioning portion adhered to the reflection layer by an adhesive layer. The light source can project light toward the light guiding plate and pass part of the light from the light guiding plate to the deflection portion due to diaphaneity of the material of the transparent film. A light emitting area can be formed around the backlight module, lightening the connection port of the electronic device or other area needed to be lightened.