Backlight Module Transparent Light Guide Structure for Privacy Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices, such as mobile phones and TVs, suffer from privacy information leakage due to light emitted from both sides of the display panel, which is caused by the wide view angle of the backlight module, leading to the visibility of private information from both sides.
Innovation Solution
A backlight module with a transparent light guide structure that changes the propagation direction of light, reducing the emergence angle from the second surface to be smaller than the incidence angle, and optionally includes microlenses and reflection layers to further converge light and reduce edge emission, thereby minimizing privacy information disclosure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a conventional light guide plate is used to uniformly transmit light, then the display panel achieves sufficient illumination, but light is emitted from both sides of the display panel causing privacy information leakage
Solution Approach 1:
The light guide plate is divided into multiple light guide regions with different light extraction characteristics. The first light guide region has first light extraction structures while the second light guide region has second light extraction structures, allowing different portions of the plate to control light extraction differently - one side extracts light for illumination while the other side suppresses light extraction to prevent privacy leakage
Solution Approach 2:
Different regions of the light guide plate are given different local properties through varying light extraction structures. The first light guide region uses structures optimized for light extraction to provide illumination, while the second light guide region uses structures that suppress light extraction on the second surface, creating localized functional differences that simultaneously achieve illumination and privacy protection
2Adaptability or versatility
If the light guide plate allows light to pass through uniformly, then the view angle of the display panel increases, but privacy information becomes visible from both sides
Solution Approach 1:
The light guide plate is segmented into distinct light guide regions with different optical functions. The first light guide region allows broad light distribution for viewing angle, while the second light guide region is specifically designed to suppress light emission from the second surface, maintaining privacy protection while preserving display visibility from the front
3Loss of energy
If light extraction structures are added to the light guide plate, then light utilization improves, but the device complexity increases
Solution Approach 1:
The patent combines multiple functions into a single integrated light guide plate structure. The plate simultaneously performs light guiding, differential light extraction on opposite surfaces, and privacy protection functions through its internal light extraction structure design, eliminating the need for separate components and reducing overall device complexity
Solution Approach 2:
The light guide plate is designed as a multi-functional component that not only guides light from the light source but also differentially extracts light on its two surfaces - one surface for illumination and the other for privacy protection. This universal design consolidates multiple optical functions into a single element, improving light utilization without proportionally increasing 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 effectively reduces the amount of light emitted from both edges of the display panel, enhancing privacy by minimizing the visibility of information from the sides, while also increasing light utilization and intensity.
Implementation Method 1
Each transparent light guide structure is configured to change a propagation direction of a first light in the light emitted by the light source, so that an emergence angle of the first light emitted from the second surface is smaller than an incidence angle of the first light incident from the first surface
Implementation Method 2
the first light emitted from the second surface of each transparent light guide structure is directed into a corresponding microlens, so as to converge the first light
Implementation Method 3
a side surface of the transparent light guide structure located between the first surface and the second surface is provided with a first reflection layer which has a reflection surface adjacent to the side surface of the transparent light guide structure
Data Source
AI summary
A backlight module comprises a light source, a light guide plate and at least one transparent light guide structure. Each transparent light guide structure comprises a first surface adjacent to a side of the light guide plate and a second surface far away from the light guide plate, a light emitted by the light source is directed into the first surface of the transparent light guide structure through the light guide plate. Each transparent light guide structure is configured to change a propagation direction of a first light in the light emitted by the light source, so that an emergence angle of the first light emitted from the second surface is smaller than an incidence angle of the first light incident from the first surface. The incidence angle of the first light onto the first surface is less than 90 degrees.