Low-Lead Microchannel Plates for Wafer-Level Image Intensifiers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional image intensifiers using microchannel plates (MCPs) with high lead oxide content are prone to failure due to the brittle nature of lead oxide, requiring individual manufacturing to prevent breakage, which increases costs and decreases throughput.
Innovation Solution
The development of image intensifier systems and methods that utilize MCPs with reduced lead oxide content, fabricated using high-volume, parallel wafer-level processing techniques, and integrate an imaging array to directly convert photons into digital images, eliminating the need for a fiber optic bundle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If MCPs with high lead oxide content are used to provide necessary electrical characteristics, then electron generation capability is improved, but device robustness deteriorates due to the brittle nature of lead oxide
Solution Approach 1:
The patent changes the chemical composition parameters of the MCP material by reducing lead oxide content from conventional high levels to below 1%, while adjusting other oxide components (such as increasing bismuth oxide to 40-70 wt%) to maintain the necessary electrical characteristics for electron generation. This parameter change resolves the contradiction by achieving both robustness through reduced brittleness and maintained electron generation capability through optimized composition.
Solution Approach 2:
The patent employs composite material design by creating a multi-oxide glass composition that combines bismuth oxide, zinc oxide, boron oxide, and other components in specific proportions. This composite approach replaces the conventional lead oxide-based single-material system, achieving both mechanical robustness and electrical functionality through synergistic material combinations.
2Strength
If conventional MCPs are manufactured individually to prevent breakage, then device robustness is maintained, but manufacturing productivity deteriorates
Solution Approach 1:
By changing the material composition to reduce lead oxide content, the patent fundamentally alters the mechanical properties of the MCP, making it sufficiently robust to withstand parallel wafer-level processing. This enables batch manufacturing of multiple devices simultaneously on a single wafer substrate, dramatically improving productivity from individual to parallel production while maintaining device robustness.
Solution Approach 2:
The patent replaces the mechanical handling and assembly process (individual device manipulation) with a wafer-level batch processing system. Multiple MCPs are processed, tested, and packaged simultaneously in parallel arrays, substituting sequential mechanical operations with parallelized fabrication processes that significantly enhance throughput.
3Device complexity
If an imaging array is integrated to directly convert photons into digital images, then manufacturing complexity is reduced by eliminating the fiber optic bundle, but device functionality changes from analog to digital output
Solution Approach 1:
The patent merges previously separate components (phosphor conversion layer and imaging sensor) into a single integrated imaging array that directly converts photons to digital signals. This consolidation eliminates the fiber optic bundle and intermediate analog transmission stages, reducing structural complexity while providing digital output capability.
Solution Approach 2:
The integrated imaging array performs multiple functions: photon detection, signal conversion, and digital image formation within a single component. This multi-functional element replaces the multi-stage analog system, reducing overall device complexity while maintaining adaptability through digital output that can be processed and displayed in various formats.
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
This approach enhances the robustness and manufacturing efficiency of image intensifiers, allowing for high-volume production while improving the ability to produce digital images of low-light scenes.
Implementation Method 1
an electron emitting photocathode disposed within the vacuum cavity for generating electrons from electromagnetic radiation transmitted through the second surface of the first substrate
Implementation Method 2
As high-energy electrons strike the conductive microchannels (which are typically tilted at an angle away from normal to encourage collisions with the microchannels' inner surfaces), the interaction causes the release of additional electrons in a process commonly referred to as secondary cascaded emission
Implementation Method 3
another (lower) charge differential typically accelerates the secondary electrons toward a phosphor screen at the other end of the intensifier, which releases a photon for every electron
Data Source
AI summary
Image intensifier systems incorporating a microchannel plate (MCP) and methods for producing the same are disclosed. A device is disclosed that includes a first substrate having a radiation-receiving first surface and an opposed second surface through which electromagnetic radiation is transmitted. A second substrate is coupled to the first substrate to define a vacuum cavity therebetween having electron-emitting photocathode is disposed therein. A microchannel plate (MCP) is disposed within the vacuum cavity and defines microchannels extending from an input end to an output end. Each of the microchannels is configured to generate/amplify electrons in response to the electrons received photocathode. The imaging array can include a plurality of metal plates connected to capacitors and configured to collect electrons from the MCP to produce a digital image responsive to electromagnetic radiation received at the first substrate and converted to electrons by the photocathode and multiplied by the MCP.