Optical Fiber Micro Array Lens for High Numerical Aperture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional microscope objectives have limitations in numerical aperture due to the use of air as the medium, restricting high-magnification imaging of integrated circuits, and require adjustments for each objective change, which is inefficient and fragile.
Innovation Solution
A micro array lens fabricated from optical fibers, arranged in a mesh with plano-convex configurations, allowing high numerical aperture compatible with silicon, enabling efficient light collection and transfer with minimal loss, suitable for semiconductor analysis.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional microscope objectives use air as the medium, then the system is simple and easy to operate, but the numerical aperture is limited to 0.95 maximum
Solution Approach 1:
The patent changes the refractive index parameter of the medium from air (n=1.0003) to silicon (n=3.42), enabling numerical aperture to exceed 1.0 and reach up to 1.40. This parameter change resolves the contradiction by allowing high numerical aperture while maintaining a relatively simple optical system configuration.
Solution Approach 2:
The patent uses a composite optical system combining silicon immersion medium with specialized lens elements, creating a hybrid system that achieves high numerical aperture (up to 1.40) while managing the complexity through integrated design of the immersion medium and optical components.
2Adaptability or versatility
If oil immersion objectives are used to achieve higher numerical aperture, then the numerical aperture increases to 1.40, but the system requires complex adjustments and additional oil medium between condenser and specimen
Solution Approach 1:
The patent changes the immersion medium from oil (n=1.515) to silicon (n=3.42), achieving even higher numerical aperture (up to 1.40) while simplifying the operational procedure. The silicon-based system eliminates the need for separate condenser adjustments and multiple medium applications, resolving the contradiction between high numerical aperture and ease of operation.
Solution Approach 2:
The silicon immersion medium serves multiple functions simultaneously: it acts as the high-refractive-index medium for the objective lens, provides mechanical support, and eliminates the need for separate condenser adjustments. This multi-functionality resolves the contradiction by achieving high numerical aperture while simplifying operation.
3Measurement precision
If high magnification lenses are used for small specimens, then imaging precision is improved, but the lenses become fragile and expensive
Solution Approach 1:
The patent changes the material parameter from traditional glass to silicon, enabling the creation of robust immersion lenses that maintain high imaging precision while significantly improving reliability. The silicon-based lenses are less fragile and more durable than conventional high-magnification lenses.
Solution Approach 2:
The patent employs a lower magnification (5x) silicon immersion lens that is more durable and cost-effective, replacing the need for expensive, fragile high-magnification lenses. This approach achieves sufficient imaging precision for IC backside analysis while improving reliability and reducing cost.
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 micro array lens provides a cost-effective solution for high collection efficiency and compatibility with silicon, enabling imaging with a larger field of view and reduced fragility compared to traditional high-magnification lenses.
Implementation Method 1
The micro array lens can efficiently collect light through the back of integrated circuits and transfer the light to a sensor or camera with minimal loss
Implementation Method 2
Each fiber from the first plurality has a flat bottom surface and a hemicylindrical top surface... Each contact of the first and second plurality of optical fibers forms a lens assembly
Data Source
AI summary
An optical fiber micro array lens is provided along with an associated fabrication method. The micro array lens is fabricated from a mesh of optical fibers. The mesh includes a first plurality of cylindrical optical fibers. Each fiber from the first plurality has a flat bottom surface and a hemicylindrical top surface. The top and bottom surfaces are aligned in parallel with a central fiber axis. The mesh also includes a second plurality of cylindrical optical fibers. Each fiber from the second plurality has a hemicylindrical bottom surface overlying and in contact with the top surfaces of the first plurality of optical fibers, and a flat top surface. The top and bottom surfaces are aligned in parallel with a central fiber axis. Each contact of the first and second plurality of optical fibers forms a lens assembly in a micro array of lenses.