Monolithic CMOS Chip for Fluorescence Lifetime Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current fluorescence and luminescence lifetime imaging technologies lack efficient, cost-effective, and high-resolution solutions for capturing chemical and biological properties, particularly in applications like oxygen sensing and skin cancer detection, due to limitations in signal modulation, power consumption, and dynamic range.
Innovation Solution
A monolithic CMOS chip integrating an imaging region and a time-to-digital converter (TDC) for direct digital phase readout, enabling frequency-domain phase-shift measurements to be converted into time-domain delays with high temporal precision and low power consumption, facilitating low-frequency signal modulation and high-resolution imaging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If frequency-domain phase measurement is used for fluorescence lifetime imaging, then measurement precision is improved, but device complexity increases due to integration requirements
Solution Approach 1:
The patent merges the photodetector, phase extraction circuit, and time-to-digital converter into a single integrated CMOS chip. This integration consolidates multiple functions that were previously separate components, achieving high measurement precision while managing device complexity through unified architecture.
Solution Approach 2:
The patent replaces complex external phase measurement instrumentation with an integrated electronic phase extraction circuit and TDC on the CMOS chip. This substitution of mechanical/external systems with integrated electronic circuits achieves precise phase measurement while reducing overall system complexity.
2Measurement precision
If high temporal resolution is achieved through ultra-fast laser pulse with sub-nanosecond resolution, then measurement precision is improved, but use of energy increases
Solution Approach 1:
The patent changes the temporal resolution parameter from sub-nanosecond (requiring ultra-fast lasers) to nanosecond-scale resolution achieved through the integrated TDC circuit. This parameter change allows achieving sufficient measurement precision with significantly lower power consumption, suitable for portable applications.
3Adaptability or versatility
If wide dynamic range is provided for temporal measurement, then adaptability is improved, but device complexity increases due to TDC design requirements
Solution Approach 1:
The integrated CMOS chip serves multiple functions: photodetector for signal reception, phase extraction circuit for phase-to-time conversion, and TDC for digital time measurement. This multi-functional integration achieves wide temporal dynamic range while managing complexity through unified circuit design.
4Ease of operation
If portable scanner design is implemented for skin cancer detection, then ease of operation is improved, but manufacturing precision requirements increase for miniaturization
Solution Approach 1:
The patent implements a nested architecture where the photodetector, phase extraction circuit, and TDC are nested within a single CMOS chip. This nesting achieves miniaturization for portable scanner design while requiring high manufacturing precision for integrating multiple functions at reduced scale.
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 provides high temporal and spatial resolution fluorescence lifetime imaging with low power consumption and a wide dynamic range, achieving sensitivity better than 0.01 degrees at 1.2 KHz and 0.1 degrees at 1 MHz, suitable for applications like oxygen sensing and skin cancer detection at a low cost.
Implementation Method 1
The imaging region includes a photodetector for receiving optical signals
Implementation Method 2
The lifetime of excited fluorescent or luminescent dyes, or of an intrinsic autofluorescent response to an excitation light, is highly sensitive and selective to chemical and/or biological properties
Implementation Method 3
The lifetime of excited fluorescent or luminescent dyes
Data Source
AI summary
Devices for use in fluorescence or luminescence lifetime imaging include a chip featuring an imaging region that includes a photodetector for receiving optical signals, and a time-to-digital converter for providing digital phase output based on the received optical signals.