Laser Module Lens Alignment via Resin Filler Height Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional laser modules using resin adhesives with inorganic fillers for bonding lenses to substrates often result in lens misalignment, causing degradation of optical characteristics due to the filler's inclination, which is difficult to control and minimize.
Innovation Solution
A laser module design where the height of the inorganic filler in the resin adhesive is limited to ensure the lens remains within a tolerable inclination angle, using a filler composition with SiO2, Mg3Si4O10(OH)2, Al2O3, AlN, BN, or TiO2, and a resin material like epoxy or acrylic, to maintain optical axis alignment and prevent beam distortion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a resin adhesive containing inorganic filler is used to attach the lens to the substrate, then the linear expansion coefficient, cure shrinkage, and thermal conductivity of the adhesive are improved, but the lens becomes inclined and misaligned, causing degradation of optical characteristics
Solution Approach 1:
The patent changes the physical parameters of the filler by controlling its height to be within a specific range (0.01 to 0.5 times the lens diameter). This parameter control allows the adhesive to maintain improved mechanical and thermal properties while preventing the lens from becoming excessively inclined, thus resolving the contradiction between adhesive performance and alignment precision.
Solution Approach 2:
The patent uses a composite adhesive material consisting of resin and inorganic filler particles. By carefully selecting and controlling the properties of the composite (particularly the filler height distribution), the adhesive achieves both improved reliability (through the filler's mechanical properties) and acceptable manufacturing precision (by limiting the filler's inclination-inducing effect).
2Strength
If the height of the inorganic filler is increased to improve adhesive properties, then the adhesive strength and thermal conductivity are enhanced, but the lens inclination angle increases beyond the tolerable angle, causing beam profile distortion
Solution Approach 1:
The patent establishes a specific parameter range for filler height (0.01 to 0.5 times the lens diameter) that balances adhesive strength requirements with optical alignment requirements. This parameter optimization ensures that the adhesive provides sufficient bonding strength while keeping the lens inclination within acceptable limits for proper optical operation.
3Stability of the object's composition
If a metal frame is used to hold the lens, then the lens positioning stability is improved, but the cost increases and the module size increases
Solution Approach 1:
The patent extracts and eliminates the metal frame component from the lens mounting structure, replacing it with a resin adhesive system. By carefully designing the adhesive system with controlled filler particles, the patent achieves sufficient lens positioning stability without the need for the complex and costly metal frame, thus simplifying the overall module structure.
Solution Approach 2:
The patent replaces the mechanical support system (metal frame) with a chemical bonding system (resin adhesive with controlled filler). This substitution eliminates the need for precise mechanical fixtures while achieving stable lens positioning through the adhesive's bonding properties and controlled filler height.
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 restricts degradation of optical characteristics by maintaining the lens within a tolerable inclination range, ensuring precise alignment and minimizing beam distortion, even with inorganic fillers, thereby enhancing the laser module's performance.
Implementation Method 1
a lens which is bonded to a surface of a substrate by a resin adhesive
Implementation Method 2
Some resin adhesives include filler (dispersed particles) whose main component is inorganic material, to adjust characteristics of the resin adhesive
Implementation Method 3
a lens which collimates or focuses a laser light emitted from a laser light source
Data Source
AI summary
[Objective]To restrict degradation of optical characteristics due to a resin adhesive containing an inorganic filler.[Means]The width d of a lens body 31 and the height of an inorganic filler 341 in a direction orthogonal to the surface of a substrate are set such that an inclination angle of a collimating lens 3 does not exceed a maximum tolerable inclination angle when the inorganic filler 341 is positioned near the width-wise center of the lens body 31. As a result, even when the inorganic filler 341 is inserted between the bottom surface of the collimating lens 3 and the top surface of the substrate 4, degradation of the optical characteristics of the laser module including skewing of the optical axis of the laser light and distortion of the beam shape of the laser light can be restricted.