Backlight Unit Optical Sheet Fixing via Guide Panel Protrusions
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Solution Overview
Problem
Liquid crystal display devices suffer from shifting of optical sheets due to external impacts, leading to uneven light distribution and the generation of bright lines on the display panel.
Innovation Solution
A backlight unit design featuring a light guide plate with a light incidence portion and a light emitting portion, where optical sheets are sequentially stacked and secured using a guide panel with sheet fixers and cutout structures, and a light shielding tape is applied to prevent shifting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the lower prism sheet is not fixed in the backlight unit, then the device complexity is reduced and ease of manufacture is improved, but the reliability deteriorates causing shifting of optical sheets under external impact
Solution Approach 1:
The guide panel is divided into a body portion and a protruding portion that acts as a separate fixing structure. The protruding portion extends through the light guide plate to securely hold the lower prism sheet, separating the fixing function from the main guide panel structure while maintaining ease of assembly.
Solution Approach 2:
The protruding portion of the guide panel serves as an intermediary fixing element between the light guide plate and the lower prism sheet. This intermediary structure provides the necessary mechanical support to prevent sheet shifting without requiring complex fixing mechanisms.
2Reliability
If sheet fixers protruding from the light guide plate are used to fix optical sheets, then the reliability is improved by preventing sheet shifting, but the device complexity increases
Solution Approach 1:
The sheet fixer function is merged into the guide panel structure itself. The protruding portion of the guide panel serves dual purposes: guiding the assembly process and fixing the optical sheets in position, eliminating the need for separate fixing components.
Solution Approach 2:
The guide panel is designed with multi-functionality, serving as both the structural support for the backlight unit and the fixing mechanism for the optical sheets. The protruding portion provides fixing functionality without requiring additional dedicated fixing components.
3Ease of operation
If the optical sheets are not securely fixed, then the ease of operation during assembly is improved, but the stability of the object's composition deteriorates causing bright line generation
Solution Approach 1:
The protruding portion of the guide panel is pre-formed to automatically position and secure the lower prism sheet during assembly. This preliminary structural arrangement ensures proper sheet positioning without requiring additional manual fixing operations, maintaining ease of assembly while ensuring stability.
Data Source
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AI summary
Discussed is a liquid crystal display including a light guide plate including a light incidence portion and a light emitting portion, a plurality of optical sheets including a diffuser sheet, a lower prism sheet and an upper prism sheet, a guide panel including a first area for seating the optical sheets and the light emitting portion of the light guide plate thereon, a second area for accommodating the light source, and a third area for accommodating the light incidence portion of the light guide plate, and a light shielding tape attached to an edge of an upper surface of the guide panel and edges of upper surfaces of the optical sheets, wherein the guide panel further includes sheet fixers each upwardly protruding from opposite lateral edges of the third area for horizontally fixing the optical sheets, and the light guide plate has cutout structures at opposite lateral edges thereof.