Optical Interferometry Speckle Correlation for Normal Flow Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current techniques for measuring fluid flow, such as Doppler frequency shift and interframe speckle variance of optical coherence tomography (OCT) images, are inadequate for measuring flow normal to the imaging beam and are insensitive to changes in flow speed.
Innovation Solution
A system and method using optical interferometry with a light source, fiber-optic system, and data processing to determine speckle patterns and calculate correlation between adjacent lines perpendicular to the flow, enabling the assessment of flow rate and displacement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If Doppler frequency shift or interframe speckle variance of OCT images is used for blood flow detection, then flow measurement is possible, but the technique cannot measure flow in a plane normal to the imaging beam
Solution Approach 1:
The patent transitions from measuring flow along the imaging beam direction to measuring flow in a plane normal to the imaging beam by analyzing speckle pattern correlations in the transverse direction. This dimensional change enables flow measurement in previously inaccessible orientations.
2Measurement precision
If speckle variance OCT (svOCT) is used for microvasculature visualization, then sensitivity is improved, but the technique is insensitive to changes in flow speed
Solution Approach 1:
The patent changes the measurement parameter from speckle variance (which detects presence of flow) to speckle pattern correlation (which detects flow speed changes). By analyzing how speckle patterns evolve over time through correlation analysis, the system becomes sensitive to flow speed variations while maintaining microvasculature detection capability.
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 allows for quantitative measurement of fluid flow in a plane normal to the imaging beam and is sensitive to changes in flow speed, as demonstrated by a close linear correlation between calculated flow speeds and pump rates in experimental validation.
Implementation Method 1
an optical detection system arranged to receive combined light from the reference beam and the observation beam and to provide detection signals
Implementation Method 2
The data processing system can be configured to use the detection signals to determine a speckle pattern corresponding to the fluid flow
Data Source
AI summary
A system for assessing the flow of a fluid. The system can include a light source, a fiber-optic system optically coupled to the light source, which is arranged to provide a reference beam and an observation beam, an optical detection system arranged to receive combined light from the reference beam and the observation beam and to provide detection signals, and a data processing system arranged to communicate with the optical detection system to receive the detection signals. The data processing system can be configured to use the detection signals to determine a speckle pattern corresponding to the fluid flow, wherein the speckle pattern includes a plurality of lines, and to calculate a correlation between adjacent lines perpendicular to the flow to determine at least one of a rate of the flow and a displacement of the flow.