Backlight Module with Bendable Reflective Sheet for Thermal Expansion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional side-type backlight modules suffer from optical quality degradation due to thermal expansion of the reflective sheet, which causes deformation and optical loss, and existing solutions fail to adequately address this issue.
Innovation Solution
A backlight module design incorporating a position-limiting unit and a reflective sheet with a bendable portion that allows the reflective sheet to expand into a gap within the position-limiting unit, maintaining its position and preventing deformation, thus ensuring optical quality and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the reflective sheet is designed with standard dimensions to ensure good light reflection performance at room temperature, then optical quality is improved, but thermal expansion at high temperature causes deformation and optical quality degradation
Solution Approach 1:
The reflective sheet is segmented into a flat portion and a bendable portion by a cutting line. The flat portion maintains optical quality at room temperature, while the bendable portion accommodates thermal expansion at high temperature by bending along the cutting line, preventing deformation of the light-emitting surface.
Solution Approach 2:
The reflective sheet's physical state changes from completely flat at room temperature to having a bent portion at high temperature. This parameter change in shape allows the sheet to accommodate thermal expansion while maintaining the flatness of the light-emitting surface for optimal optical performance.
2Stability of the object's composition
If the dimension of the reflective sheet is reduced to prevent thermal expansion deformation, then dimensional stability is improved, but a gap forms between the reflective sheet and light-emitting unit at room temperature causing optical loss
Solution Approach 1:
The reflective sheet transitions from a static flat structure to a dynamic structure with a bendable portion that can change shape in response to temperature changes. At room temperature, the sheet extends fully beneath the light-emitting unit for optimal reflection. At high temperature, the bendable portion bends to accommodate expansion while the flat portion maintains contact.
3Stability of the object's composition
If the reflective sheet is allowed to expand freely at high temperature, then dimensional stability is maintained, but the sheet abuts on other components and deforms harming optical quality
Solution Approach 1:
The reflective sheet is segmented into a flat portion and a bendable portion by a cutting line. The flat portion maintains optical quality at room temperature, while the bendable portion accommodates thermal expansion at high temperature by bending along the cutting line, preventing deformation of the light-emitting surface.
4Ease of manufacture
If dimension allowance is designed for manufacturing and assembly tolerances, then ease of manufacture is improved, but the reflective sheet cannot maintain proper position under thermal expansion
Solution Approach 1:
The reflective sheet transitions from a static flat structure to a dynamic structure with a bendable portion that can change shape in response to temperature changes. At room temperature, the sheet extends fully beneath the light-emitting unit for optimal reflection. At high temperature, the bendable portion bends to accommodate expansion while the flat portion maintains contact.
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 prevents optical quality degradation and optical loss by accommodating thermal expansion of the reflective sheet, enhancing manufacturing and assembly convenience, and maintaining luminous efficiency.
Implementation Method 1
As the reflective sheet expands along the abutting direction, the bendable portion of the reflective sheet extends into the gap of the position-limiting unit along the guiding surface of the position-limiting unit
Data Source
AI summary
The present invention provides a backlight module having a backplate, a position-limiting unit, a reflective sheet, a light guiding plate, and a light-emitting unit. The position-limiting unit is disposed on the backplate and has a position-limiting surface, a guiding surface, and a gap. The reflective sheet is disposed on the backplate and has a first side edge, a second side edge, a cutting line extending inward from the first side edge, and a bendable portion formed between the cutting line and the second side edge. The bendable portion abuts the position-limiting surface of the position-limiting unit and is guided by the guiding surface to extend into the gap as the reflective sheet expands along the position-limiting surface. The present invention also provides a display device having aforementioned backlight module and a display panel.