Co-extruded Light-guide with Micro-structure for Uniform Backlight
Solution Overview
Problem
Conventional backlight assemblies for display devices suffer from light loss, increased production costs, ill-visibility due to line defects, and manufacturing difficulties caused by air spacing between light-guide and reflection plates, as well as non-uniform brightness distribution due to glazing bands.
Innovation Solution
A uniform reflective light-guide apparatus with a micro-structure is created using a co-extrusion process, integrating a light-guiding layer and a reflective layer as a unique piece, eliminating air spacing and incorporating micro-structures and diffusing particles to enhance light reflection and distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a reflection plate is added to increase light reflection efficiency, then light reflection performance is improved, but air spacing between plates causes light loss up to 8% and increases manufacturing cost
Solution Approach 1:
The patent merges the light-guide plate and reflection plate into a single integrated component with a reflective layer formed directly on the bottom surface of the light-guide plate. This eliminates the air spacing between separate plates, preventing light loss at interfaces while maintaining high light reflection efficiency. The co-extrusion process creates a unified structure where the reflective layer is continuously formed without gaps.
Solution Approach 2:
The patent uses composite materials by incorporating a reflective layer made of reflective particles suspended in a transparent matrix material directly into the light-guide plate structure during co-extrusion. This composite approach integrates reflection functionality within the light-guide material itself, eliminating the need for separate reflection plates and associated air gaps.
2Illumination intensity
If additional printing processes are applied to the light-guide plate, then light uniformity is improved, but production cost increases and manufacturing complexity increases
Solution Approach 1:
The patent combines multiple functions (light guiding, light reflection, and light uniformity distribution) into a single co-extruded light-guide plate structure. The reflective layer and light-guiding channels are formed simultaneously in one manufacturing process, eliminating the need for separate printing or coating processes that would be required if these functions were implemented as separate components.
Solution Approach 2:
The patent achieves light uniformity by controlling the geometric parameters of the light-guiding channels and reflective layer during the co-extrusion process. By adjusting channel depth, width, spacing, and reflective layer properties, uniform light distribution is achieved without requiring additional post-processing printing steps.
3Ease of manufacture
If separate light-guide plate and reflection plate are used, then manufacturing flexibility is maintained, but air spacing causes line defects and reduces production yield
Solution Approach 1:
The patent integrates the light-guide plate and reflection plate into a single monolithic structure manufactured by co-extrusion. This unified structure eliminates air spacing between components, preventing line defects caused by misalignment or gaps while maintaining manufacturing flexibility through the co-extrusion process that can accommodate various channel configurations.
4Reliability
If conventional multi-component backlight assembly is used, then functional requirements are met, but production cost increases due to multiple components and assembly steps
Solution Approach 1:
The patent combines multiple functional components (light-guide plate, reflection plate, and light-guiding channels) into a single integrated light-guide plate manufactured by co-extrusion. This reduces the number of parts and assembly steps while maintaining all necessary optical functions, thereby reducing production cost without compromising functional performance.
Solution Approach 2:
The integrated light-guide plate performs multiple functions simultaneously: it guides light from the edge source, reflects light back into the plate, and distributes light uniformly across the display area. This multi-functionality eliminates the need for separate components, reducing both part costs and assembly complexity.
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 significantly reduces light loss to less than 4%, improves light utilization efficiency, simplifies manufacturing, and enhances luminance and uniformity, while reducing production costs and eliminating line defects.
Implementation Method 1
The light-guide plate is to direct the incident lights to a particular side (usually the front surface) of the plate
Implementation Method 2
the bottom surface of the light-guide plate is usually formed as a reflection surface to send back lights into the plate
Implementation Method 3
a three-dimensional micro structure is constructed onto the reflective surface
Implementation Method 4
manufactured by a co-extrusion process and capable of light reflection, distribution and guiding
Data Source
AI summary
A uniform reflective light-guide for accompanying an edge light source to form a backlight module for an LCD display includes a light-guiding layer and a reflective layer. The light-guiding layer further defines a light-introducing surface and a light-exiting surface. The light-introducing surface is to allow lights emitted from the edge light source to enter the light-guiding layer. The light-exiting surface perpendicular to the light-introducing surface is to allow at least a portion of the lights to leave the light-guiding layer. The reflective layer is to reflect the incident lights back to the light-guiding layer. The reflective layer and the light-guiding layer are manufactured integrally into a unique piece by a co-extrusion process so as to avoid possible existence of an air spacing in between. A reflective surface is defined to interface the reflective layer and the light-guiding layer, and a three-dimensional micro-structure is constructed on the reflective surface.