Lens Cap Bonding Structure for Sensor Module Position Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing sensor module designs face issues with positional shift and flaking of the lens cap due to vibration or impact during conveyance before the bonding agent is cured, and subsequent contraction and curing of the bonding agent, which can lead to image capturing deficiencies and focus loss in infrared sensors.
Innovation Solution
A sensor module design featuring a lens cap with a cap edge part that has a cutout on its outer side surface, allowing the ultraviolet-curing type bonding agent to enter and be temporarily cured, ensuring stable positioning and increased bonding strength, thereby preventing positional shifts and flaking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the bonding area with the bonding agent is increased to prevent breaking and flaking after curing, then bonding strength is improved, but positional shift and flaking during conveyance before curing cannot be prevented
Solution Approach 1:
The patent applies ultraviolet-curing type bonding agent that can be temporarily cured by ultraviolet irradiation before final heating curing. This preliminary ultraviolet curing action stabilizes the lens cap position during conveyance, preventing positional shift and flaking, while the increased bonding area ensures sufficient bonding strength after final curing.
2Reliability
If ultraviolet-curing type bonding agent is used with temporary curing, then positional shift during conveyance can be prevented, but the bonding agent cannot be irradiated with ultraviolet from above the lens cap due to space constraints
Solution Approach 1:
The patent introduces a light source that irradiates ultraviolet light from the side direction (perpendicular to the optical axis) rather than from above. This dimensional change in light source positioning enables ultraviolet curing of the bonding agent at the side surface of the lens cap, solving the space constraint problem while maintaining temporary curing capability.
3Reliability
If the bonding agent is irradiated with ultraviolet to temporarily cure, then positional shift due to vibration or impact can be prevented, but the bonding agent contracts at curing causing positional shift of the lens cap
Solution Approach 1:
The patent performs preliminary ultraviolet curing to temporarily fix the lens cap position during conveyance, then performs final heating curing after the module is assembled. This two-stage curing approach separates the positional stabilization function from the final bonding function, minimizing positional shift while ensuring reliable bonding.
Solution Approach 2:
The patent uses periodic action by applying ultraviolet irradiation at specific stages (after lens cap attachment but before final assembly) rather than continuous curing. This timed, periodic curing approach allows positional stabilization when needed while avoiding contraction issues during final positioning.
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 positional shifts and flaking of the lens cap during conveyance and curing, ensuring reliable image capturing and extended lifespan of the sensor module by enhancing bonding strength and stability.
Implementation Method 1
an ultraviolet-curing type bonding agent bonding an upper surface of the substrate and a lower surface of the lens cap
Implementation Method 2
since the bonding agent contracts at curing, the curing time and contraction amount of the bonding agent are different between places due to variance of heating temperature
Data Source
AI summary
A sensor module comprising:A sensor chip (5) is provided on an upper surface of the substrate (1). A lens (7) is provided above the sensor chip (5) such that a light receiving unit of the sensor chip (5) is positioned in a projection area. A lens cap (8) includes a cap body (8a) surrounding the sensor chip (5) to hold the lens (7), and a cap edge part (8b) protruding outward from a lower end part of the cap body (8a). An ultraviolet-curing type bonding agent (9) bonds the upper surface of the substrate (1) and a lower surface of the lens cap (8). A cutout (10) is provided on an outer side surface of the cap edge part (8b). The bonding agent (9) enters in the cutout (10).