Metallised Waveguide Manufacturing for Thin Backlights
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current illumination systems for displays and environmental lighting face challenges in providing efficient, uniform, and switchable illumination with reduced solid angle, particularly for privacy displays and high dynamic range applications, due to the complexity and cost of existing optical stacks and the need for thin, flexible designs.
Innovation Solution
A method of manufacturing a waveguide with metallised wells using a continuous layer, alignment layer, and well layer, where metal is deposited across the outer side and exposed regions, allowing for alignment and attachment in a single step, reducing cost and complexity, and enabling a thin, efficient, and uniform illumination apparatus for LCD backlighting and environmental lighting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If multiple optical components are used to achieve high efficiency illumination, then illumination efficiency is improved, but total backlight thickness increases to 1 mm or greater
Solution Approach 1:
The patent combines multiple optical functions (light input, total internal reflection, light extraction, and turning) into a single integrated waveguide component. This eliminates the need for separate optical components and reduces the overall backlight thickness while maintaining high illumination efficiency through the waveguide's internal optical paths.
Solution Approach 2:
The waveguide serves multiple functions simultaneously: it guides light from LEDs, provides total internal reflection to control light distribution, extracts light at specific locations, and redirects light direction. This multi-functionality reduces the number of separate components needed and decreases overall system thickness.
2Length of stationary object
If edge illuminated light guide plate is used, then thickness is reduced, but it is not appropriate for two-dimensional local dimming for HDR-LCD illumination
Solution Approach 1:
The waveguide is divided into multiple discrete light input locations and light extraction locations, enabling independent control of different illumination zones. This segmentation allows for two-dimensional local dimming by selectively activating or adjusting the intensity of individual LED locations and their corresponding extraction regions, achieving HDR-LCD illumination requirements.
3Illumination intensity
If packaged LEDs with batwing optical elements are used, then illumination distribution is improved, but alignment complexity and cost increase
Solution Approach 1:
The patent integrates the batwing optical element functionality directly into the waveguide structure through precisely positioned light extraction features and internal reflections. This eliminates the need for separate packaged LEDs with attached batwing elements, significantly reducing alignment complexity and manufacturing cost while maintaining controlled illumination distribution.
4Adaptability or versatility
If switchable polarisation control layers are added for privacy function, then privacy capability is improved, but device complexity increases
Solution Approach 1:
The waveguide provides localized light extraction at specific positions and angles through its structured design. By controlling which light extraction locations are active and at what angles, the system can provide directional illumination that inherently provides privacy functionality without requiring additional switchable polarisation control layers, thus avoiding increased device 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
The solution provides a thin, efficient, and high-uniformity illumination system that can be used for both display backlighting and environmental lighting, achieving localized output and reduced visibility of hot spots, while supporting high dynamic range and privacy functions.
Implementation Method 1
attaching the alignment layer to a surface of the continuous layer by the adhesive layer
Implementation Method 2
depositing metal continuously across an outer side of the capping layer and the plurality of regions of the surface of the continuous layer that are exposed
Implementation Method 3
Light that propagates by total internal reflection within the waveguide
Implementation Method 4
surface features that adjust the propagation angle of light within the waveguide and allow extraction at angles close to grazing the outside of the waveguide
Implementation Method 5
Such light is directed in a normal direction to the LCD by means of a turning film and/or rear reflectors
Data Source
AI summary
Forming an array of metallised light input wells and an array of light-deflecting wells in an optical waveguide involves the steps of forming holes through a capped adhesive layer, attaching the adhesive layer to a substrate, metallising the substrate and adhesive layer and removing the capping to expose adhesive and metallised regions. The substrate is aligned to a well layer with an array of light input through-holes and an array of light-deflecting through-holes. The substrate is attached to the well layer with an array of metallised light input wells and an array of metallised light-deflecting wells. The array of light input wells receive light from a respective aligned array of light-emitting diodes. The array of light-deflecting wells reflects guided light in the region around each light-emitting diode. Extracted light from the waveguide is output by refraction and total internal reflection by a light turning optical component.