Self-Referenced SPR Detection Using Common Optical Path
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Surface plasmon resonance (SPR) detection systems in interferometer configurations are susceptible to environmental noise such as vibrations and temperature fluctuations, leading to misalignment and reduced sensitivity in detecting and imaging sample arrays.
Innovation Solution
A self-referencing detection and imaging system is implemented, using a common optical path with a phase difference generator to introduce pathlength differences and an imaging spectrometer for spectral separation, allowing for simultaneous detection and imaging of sample arrays without separate reference and sample paths, thereby minimizing noise and enhancing sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If two different paths (reference arm and sample arm) are used in an interferometer configuration, then the system can perform SPR detection, but the system becomes susceptible to environmental factors such as vibrations causing misalignment and noise
Solution Approach 1:
The patent merges the reference path and sample path into a single common optical path. The light beam passes through the sensing surface containing both reference regions and sample regions in sequence, eliminating the need for separate reference and sample arms. This consolidation removes the misalignment issues between two separate paths while maintaining the ability to perform differential measurements between reference and sample regions.
Solution Approach 2:
The patent introduces a phase difference generator as an intermediary component that deliberately introduces a known phase shift between the reference beam and sample beam within the common optical path. This controlled phase modulation enables differentiation between reference and sample signals while operating within a single stable optical path, avoiding the environmental sensitivity problems of dual-path interferometers.
2Object-affected harmful factors
If a common optical path is used with self-referencing, then environmental noise is reduced, but a phase difference generator is required to introduce pathlength differences
Solution Approach 1:
The phase difference generator modifies the optical path by introducing a controlled phase shift or pathlength difference between reference and sample beams. This parameter change enables the system to distinguish between reference and sample signals while maintaining a common optical path, achieving noise reduction without requiring complex separate paths.
3Measurement precision
If separate reference and sample paths are used, then reference and sample can be measured independently, but misalignment occurs due to vibrations affecting sensitivity
Solution Approach 1:
The patent combines reference and sample measurements into a single stable optical path, eliminating alignment drift between separate paths. The common optical path ensures that both reference and sample beams experience identical environmental conditions, maintaining stable relative alignment while enabling precise differential measurements through phase modulation.
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 enables high-throughput, noise-reduced detection and imaging of sample arrays by eliminating the need for separate optical paths, improving sensitivity and stability, and allowing for real-time monitoring of molecular interactions.
Implementation Method 1
a phase difference generator configured to introduce differences in pathlengths of one or more samples in the array of samples
Implementation Method 2
an imaging spectrometer configured to image one or more samples in the array of samples
Implementation Method 3
A light beam incident on the sample excites surface plasmons in the thin metal layer in a resonant manner. The surface plasmons propagate in a direction parallel to the interface formed between the thin metal layer and the prism (metal/prism interface). Since the surface plasmons are present at the boundary of the thin metal layer and an external medium, the oscillations of the surface plasmons are responsive to any changes in the boundary of the metal and the external medium
Implementation Method 4
interfering a resultant reference beam with resultant sample beams to form interference spectra
Data Source
AI summary
A system for detecting an array of samples having detectable samples and at least one reference sample is provided. The system comprises an electromagnetic radiation source, a sensing surface comprising a plurality of sample fields, wherein the plurality of sample fields comprise at least one reference field, a phase difference generator configured to introduce differences in pathlengths of one or more samples in the array of samples, and an imaging spectrometer configured to image one or more samples in the array of samples.