Planar Waveguide Optofluidic Sensor for Refractive Index Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing refractive index sensors face challenges in cost-effectiveness, complex manufacturing processes, and lack of real-time detection capabilities, making them unsuitable for mass production and commercial applications.
Innovation Solution
A planar waveguide-based optofluidic sensor is developed, featuring a substrate, adhesive layer, waveguide plate, and microfluidic module layer, which allows for real-time refractive index detection using a simple and inexpensive light source system and metal nanoparticle layer for enhanced sensitivity, eliminating the need for vacuum and photolithography processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If vacuum manufacturing processes (thin-film deposition, dry etching, electron beam lithography) are used for sensor manufacturing, then manufacturing precision is improved, but device complexity and production time increase
Solution Approach 1:
The patent replaces expensive, complex vacuum-based manufacturing processes with simple, low-cost wet etching and spin coating methods. The sensor structure uses readily available materials and standard laboratory equipment, eliminating the need for electron beam lithography and thin-film deposition, thereby reducing manufacturing complexity while maintaining sufficient precision for the application
Solution Approach 2:
The patent substitutes mechanical/vacuum-based manufacturing processes with chemical-based wet etching and spin coating techniques. This replacement uses liquid chemicals and centrifugal force instead of vacuum equipment, significantly simplifying the manufacturing system while achieving the required structural precision
2Manufacturing precision
If vacuum manufacturing processes are used for sensor manufacturing, then manufacturing precision is improved, but productivity decreases
Solution Approach 1:
The patent adopts simple, rapid wet etching and spin coating processes that can be performed in minutes using standard laboratory equipment, replacing time-consuming vacuum processes. This enables faster production cycles and higher throughput while maintaining adequate manufacturing precision
Solution Approach 2:
The patent performs preliminary surface preparation and pattern formation through spin coating and simple etching steps before final assembly, allowing for rapid manufacturing without requiring complex sequential vacuum processes. This preliminary action approach streamlines the workflow and increases production efficiency
3Measurement precision
If wavelength- or polarization-based sensing methods are used, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent replaces complex optical systems requiring wavelength or polarization modulation with a simple intensity-based detection method. The sensor uses a basic light source and photodetector to measure light intensity changes caused by refractive index variations, eliminating the need for spectrometers, lasers, or polarization control components
Solution Approach 2:
The patent uses a simplified optical path that copies the essential sensing function without requiring complex wavelength or polarization analysis. The intensity-based method captures the refractive index information through direct light transmission measurements, providing a simpler equivalent to the more complex spectral or polarization-based approaches
4Measurement precision
If high-stability laser devices and high-resolution spectrometers are used for optical reading, then measurement precision is improved, but device complexity and cost increase
Solution Approach 1:
The patent replaces expensive, high-precision instruments (lasers, spectrometers) with inexpensive, commercially available components such as LED light sources and standard photodetectors. This substitution maintains sufficient detection precision for practical applications while dramatically reducing system complexity and cost
Solution Approach 2:
The patent substitutes complex spectral analysis systems with simple intensity-based detection. The measurement system uses basic light transmission measurements rather than sophisticated spectral or polarization analysis, eliminating the need for high-resolution spectrometers and stable laser devices
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 enables high-sensitivity, real-time refractive index detection with reduced production costs and simplified manufacturing, making it suitable for mass production and practical commercial use.
Implementation Method 1
Waveguide (WG) is a conventional light-propagation optical device
Implementation Method 2
the field (evanescent field) distribution of the waveguide mode is closely related to the refractive index of the core and the cladding layer
Implementation Method 3
a metal nanoparticle layer may be further disposed on the planar waveguide, and the high sensitivity of metal nanoparticles helps to enhance the performance of sensors
Data Source
AI summary
A planar waveguide-based optofluidic sensor and use thereof are provided, wherein the optofluidic sensor includes a substrate, an adhesive layer, a waveguide plate, and a microfluidic module layer. The adhesive layer is disposed on both sides of the substrate, the waveguide plate s disposed on the adhesive layer to be bonded with the substrate, and a hollow gap is formed between the substrate and the waveguide plate by the adhesive layer, and the microfluidic module layer is disposed on the waveguide plate and has a microfluidic channel, a fluid sample injection port, and an output port. The optofluidic sensor may detect the refractive index of the fluid sample with high sensitivity.