Resin HUD Mirror Rib Structure to Prevent Sink Marks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing technologies struggle to maintain a simple configuration of a mirror unit in a head-up display device that enhances strength while preventing sink marks and maintaining image quality.
Innovation Solution
A mirror unit with a substantially rectangular plate-shaped main body formed of synthetic resin, featuring a reflection layer, shaft portions, and ribs that extend in a specific direction, with rib widths equal to or greater than 50% of the main body's thickness, integrated to improve strength and prevent sink marks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the widths of the ribs are increased to increase the strength, then the strength is improved, but a sink mark is generated and the shape accuracy of the reflection surface deteriorates
Solution Approach 1:
The rib width is set to be equal to or less than half the thickness of the main body plate portion, creating a local structural optimization that prevents sink marks while maintaining strength. This local quality control at the rib interface resolves the contradiction between strength enhancement and surface accuracy preservation
2Device complexity
If the configuration is made simple by vapor-depositing metal on the holder, then the device complexity is reduced, but the strength is insufficient when ribs are provided
Solution Approach 1:
The holder and reflection surface are merged into a single integrated structure where the holder main body plate portion serves dual functions as both structural support and reflection surface substrate. The metal layer is vapor-deposited directly on this integrated structure, combining simplicity with enhanced strength through the rib configuration
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 configuration maintains image quality by enhancing the mirror unit's strength without generating sink marks, allowing for improved resilience and reduced vibration.
Implementation Method 1
a reflection layer that is formed on one surface of the main body plate portion and reflects display light
Data Source
AI summary
To provide a mirror unit and a head-up display device capable of suppressing deterioration in image quality while further increasing strength with a simple configuration. A mirror unit includes: a substantially rectangular plate-shaped main body plate portion formed of a synthetic resin; a reflection layer that is formed on one surface of the main body plate portion and reflects display light; two shaft portions provided at end portions on both sides in an X direction; and a rib that is erected on the other back surface of the main body plate portion and extends in a rib extending direction V. The rib is formed such that a width of the rib in a direction orthogonal to the rib extending direction V has a length equal to or more than 50% of a thickness of the main body plate portion.