Fingerprint Sensor Mount With Air Gap for Thermal Expansion Relief
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Structural deformation due to thermal expansion of the filling member in the through hole of a metal plate in display devices, which affects the performance of fingerprint sensors.
Innovation Solution
A display device design that includes a metal plate with a through hole filled by a filling member of a different material, with an air gap between the side surfaces of the filling member and the metal plate, and a bonding member to secure the fingerprint sensor to the filling member, reducing structural deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a filling member is disposed in the through hole of the metal plate, then the structural stability is improved, but thermal expansion of the filling member causes structural deformation
Solution Approach 1:
A buffer member is introduced as an intermediary element disposed between the filling member and the metal plate. This buffer member absorbs the thermal expansion forces of the filling member, preventing direct transmission of expansion forces to the metal plate and fingerprint sensor, thereby eliminating structural deformation while preserving structural stability.
Solution Approach 2:
The harmful thermal expansion effect is extracted and isolated from the main structure by placing the filling member in a through hole rather than having it directly bonded to the metal plate. This spatial separation allows the filling member to expand without affecting the overall structural integrity.
2Ease of manufacture
If the filling member is directly bonded to the metal plate, then the manufacturing process is simplified, but thermal expansion causes deformation of the fingerprint sensor
Solution Approach 1:
The buffer member serves as a mediator that decouples the thermal expansion of the filling member from the metal plate and fingerprint sensor. This allows the filling member to be bonded to the metal plate without causing deformation, maintaining both manufacturing simplicity and sensor alignment precision.
3Reliability
If the filling member material is different from the metal plate material, then thermal expansion differences are reduced, but structural deformation still occurs
Solution Approach 1:
Even when using materials with different thermal expansion coefficients, the buffer member acts as a mediator to absorb expansion forces. This additional protective layer ensures that minor thermal expansion differences do not translate into structural deformation, enhancing both reliability and structural stability.
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
Reduces structural deformation caused by thermal expansion, enhancing the accuracy and reliability of fingerprint authentication by maintaining the integrity of the fingerprint sensor's operation.
Implementation Method 1
Structural deformation due to thermal expansion of the filling member in the through hole of a metal plate
Implementation Method 2
a bonding member disposed between the fingerprint sensor and the filling member and that bonds the fingerprint sensor to the filling member
Data Source
AI summary
A display device includes a display panel; a metal plate and a filling member disposed on a same layer on a bottom surface of the display panel and that include different materials; a fingerprint sensor disposed on a bottom surface of the filling member and that overlaps the filling member; and a member-sensor bonding member disposed between the fingerprint sensor and the filling member and that bonds the fingerprint sensor to the filling member. At least a part of a side surface of the filling member and a side surface of the metal plate are spaced apart from each other with an air gap therebetween.