Optical Hydration Sensing with Dual-Wavelength Absorption Normalization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for monitoring hydration, such as impedance and MRI, are inaccurate, inconvenient, or require bulky and expensive equipment, while optical methods lack specificity in distinguishing water-dependent and water-independent absorption for precise hydration estimation.
Innovation Solution
A wearable device with optical sensors that emit and detect radiation at specific water-dependent and water-independent wavelengths, normalizing these parameters to determine a hydration index, providing real-time, non-invasive hydration monitoring.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If impedance or MRI methods are used for hydration monitoring, then measurement accuracy is improved, but device complexity and cost increase significantly
Solution Approach 1:
The patent replaces complex mechanical/electrical systems (impedance sensors, MRI machines) with an optical system using light-emitting diodes and photodetectors. This substitution maintains measurement capability while dramatically reducing device complexity and cost, allowing hydration monitoring in wearable form factors.
Solution Approach 2:
The patent changes the measurement parameter from electrical impedance or magnetic resonance signals to optical absorption characteristics. By measuring light absorption at specific wavelengths that correspond to water absorption peaks, the system achieves accurate hydration measurement through a simpler optical parameter rather than complex electrical or magnetic measurements.
2Ease of operation
If optical sensors are used for hydration monitoring, then ease of operation is improved, but measurement precision deteriorates due to inability to distinguish water-dependent and water-independent absorption
Solution Approach 1:
The patent segments the optical absorption measurement into multiple discrete wavelength channels. By measuring absorption at several specific wavelengths (including water absorption peaks and isosbestic points), the system can distinguish between water-dependent and water-independent absorption components, thereby improving measurement precision while maintaining ease of operation.
Solution Approach 2:
The patent introduces wavelength-selective filtering as an intermediary mechanism between the broadband light source and the photodetector. This allows selective measurement of absorption at specific wavelengths corresponding to water absorption characteristics, enabling precise hydration estimation while keeping the optical sensor system simple and easy to operate.
3Measurement precision
If multiple wavelengths are used to distinguish water-dependent and water-independent absorption, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent merges multiple wavelength measurements into a single integrated optical sensor module. By combining LED light sources at different wavelengths, wavelength-selective filters, and photodetectors into one compact unit, the system achieves multi-wavelength measurement capability without proportionally increasing device complexity, making the solution practical for wearable applications.
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
Accurately and conveniently monitors hydration levels in real-time, addressing the limitations of existing methods by using optical sensors to differentiate water-dependent and water-independent absorption for precise hydration estimation.
Implementation Method 1
The theoretical basis of this technique is the Beer-Lambert law, which states that the concentration c i of an absorbent in solution can be determined by the intensity of light transmitted through the solution, knowing the pathlength d λ , the intensity of the incident light I 0,λ , and the extinction coefficient ε i,λ at a particular wavelength λ.
Implementation Method 2
The one or more optical detectors can detect the optical radiation emitted by the one or more optical detectors after attenuation through the tissue of the subject
Data Source
Figure 1A
Figure 1B~1C
Figure 1D~1E
AI summary
The present disclosure provides a physiological monitoring system that can include a hardware processor. The hardware processor can access first optical data corresponding to a water-dependent radiation wavelength attenuated through a medium and detected at a detector. The hardware processor can access second optical data corresponding to a water-independent radiation wavelength attenuated through the medium and detected at the detector. The hardware processor can determine a hydration index of the medium based on the first and second optical data.