Backlight Module Parallel Light Emission via Reflective Sloped Surfaces
Solution Overview
Problem
Existing backlight modules for portable devices face challenges in achieving parallel light emission without significant brightness loss, requiring additional anti-peep films that are inconvenient to install and detach, leading to poor user experience and increased device thickness.
Innovation Solution
A backlight module design featuring a light guide plate with reflective sloped surfaces and a light-emitting assembly that includes a parabolic reflector or collimating lens, allowing for parallel light emission without the need for anti-peep films, ensuring minimal brightness loss and improved user experience through adjustable light angles using a liquid crystal layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If anti-peep films are added to achieve parallel light emission and privacy protection, then privacy protection is improved, but device thickness increases and user experience deteriorates
Solution Approach 1:
The patent extracts and eliminates the need for separate anti-peep films by integrating the privacy protection function directly into the backlight module structure. The light guide plate with specific refractive index and the reflective sloped surfaces work together to provide parallel light emission and privacy protection without requiring additional film layers, thereby reducing device thickness while maintaining privacy protection.
Solution Approach 2:
The patent merges multiple functions into the light guide plate structure. The light guide plate simultaneously performs light guidance, parallel light emission, and privacy protection functions. By combining these functions into a single integrated component rather than using separate films and structures, the device thickness is reduced while achieving both parallel light emission and privacy protection.
2Illumination intensity
If anti-peep films are installed to achieve parallel light emission, then parallel light emission is improved, but ease of operation deteriorates due to inconvenient installation and detachment
Solution Approach 1:
The patent merges the parallel light emission function into the intrinsic structure of the backlight module, specifically through the light guide plate with specific refractive index and reflective sloped surfaces. This integration eliminates the need for separate, removable anti-peep films, making the system inherently capable of parallel light emission without requiring users to install or detach additional components.
Solution Approach 2:
The backlight module structure itself provides the parallel light emission capability through its designed optical paths and reflective surfaces. The system is self-sufficient and does not require external anti-peep films or additional user actions to achieve parallel light emission, thereby improving ease of operation.
3Illumination intensity
If additional optical films are used to achieve parallel light emission, then parallel light emission is improved, but device complexity increases
Solution Approach 1:
The patent combines multiple optical functions into a single light guide plate structure. The light guide plate with refractive index between 1.3 and 1.7, combined with reflective sloped surfaces, simultaneously achieves light guidance, parallel light emission, and privacy protection. This integration reduces the number of separate optical components and simplifies the overall optical structure.
Solution Approach 2:
The light guide plate serves multiple functions: it guides light from the light source, creates parallel light emission through its specific refractive index and geometry, and provides privacy protection through reflective sloped surfaces. This multi-functionality eliminates the need for separate specialized components, thereby reducing 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 enables efficient parallel light emission without brightness loss, reduces device thickness, and enhances user experience by allowing easy switching between narrow and wide angles of view using a liquid crystal layer, eliminating the need for additional optical films and improving operational convenience.
Implementation Method 1
The reflective sloped surface is positioned between the bottom surface and the light emitting surface, and an angle between the at least one reflective sloped surface and a plane of the bottom surface extending in a direction away from the light incident surface is less than 90°
Implementation Method 2
the light-emitting assembly comprises a light-emitting device and a reflector that has a parabolic structure to encapsulate the light-emitting device
Implementation Method 3
the light-emitting assembly comprises a light-emitting device and a collimating lens, wherein the collimating lens is positioned between the light-emitting device and the light incident surface
Implementation Method 4
the liquid crystal layer comprises a polymer dispersed liquid crystal... the liquid crystal layer for regulating an emission state of the parallel light rays emitted from the backlight module
Data Source
AI summary
The present disclosure relates to a backlight module and a display device. The backlight module comprises a light guide plate and a light-emitting assembly configured to emit light rays and cause the light rays as emitted to be incident to the light guide plate in parallel. The light guide plate further comprises a light incident surface, a bottom surface, a light emitting surface on the top thereof, and at least one reflective sloped surface. The reflective sloped surface is positioned between the bottom surface and the light emitting surface, and an angle between the at least one reflective sloped surface and a plane of the bottom surface extending in a direction away from the light incident surface is less than 90°. The light incident surface is located on a side of the light guide plate.