Mach-Zehnder Interferometer for Dynamic Light Scattering

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional dynamic light-scattering measuring devices based on single scattering theory fail to accurately measure particle size in high-concentration solutions due to multiple scattering phenomena, leading to inaccurate measurements and inability to quantify fine particles below 100 nm in diameter.

Innovation Solution

Incorporating a Mach-Zehnder interferometer with a low-coherence light source and adjusting the fiber branching ratio and microscope optical system, allowing for enhanced light collection and sensitivity, thereby preventing detector saturation and enabling precise measurement of particle sizes in high-concentration fine particle solutions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If conventional single scattering theory is used for measurement, then measurement simplicity is maintained, but measurement precision deteriorates in high-concentration solutions due to multiple scattering phenomena

Engineering Contradiction:
Improvemeasurement simplicityVSAvoidparticle size measurement accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The patent introduces a Mach-Zehnder interferometer as an intermediary device between the light source and detector. This interferometer separates single scattering light from multiple scattering light by creating interference patterns, allowing only single scattering components to reach the detector. This resolves the contradiction by maintaining operational simplicity while achieving precise measurements in high-concentration solutions through the intermediary filtering mechanism.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If light collection is enhanced to improve sensitivity, then detection capability improves, but detector saturation occurs

Engineering Contradiction:
Improvedetection sensitivityVSAvoiddetector saturation
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent extracts only the single scattering light component from the total scattered light using the Mach-Zehnder interferometer. By separating and selecting only the useful single scattering component while excluding multiple scattering components, the system enhances detection sensitivity for fine particles without causing detector saturation, as the extracted signal is optimized for the detection range.

Inventive Principle:
Principle #2Taking out (Extraction)

3Measurement precision

If fiber branching ratio is adjusted to optimize light distribution, then light collection efficiency improves, but system complexity increases

Engineering Contradiction:
Improvelight collection efficiencyVSAvoidoptical system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent employs adjustable fiber branching ratios that can be dynamically optimized for different measurement conditions. The optical system allows adjustment of light distribution through the fiber bundle configuration, enabling optimal light collection efficiency for various particle concentrations and sizes while maintaining a modular structure that manages system complexity through standardized adjustable components.

Inventive Principle:
Principle #15Dynamics

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 allows for accurate measurement of particle sizes down to 10 nm with enhanced sensitivity, overcoming the limitations of conventional methods by preventing detector saturation and improving light scattering intensity, enabling precise analysis of multi-disperse states and high-concentration samples.

Implementation Method 1

a low-coherence light source (1) having a coherence length of 0.1 to 1000 μm

Methodology Applied
Scientific EffectLow-coherence light emission:

Implementation Method 2

dynamic light-scattering measuring apparatus (10) comprising a low-coherence light source (1), a Mach-Zehnder interferometer (100)

Methodology Applied
Scientific EffectOptical interference: Interference

Implementation Method 3

method for measuring light-scattering intensity of particles in a medium

Methodology Applied
Scientific EffectLight scattering: Scattering

Implementation Method 4

an objective lens (12) as a light collecting device

Methodology Applied
Scientific EffectLight collection and focusing: Lens

Data Source

PatentEP2270449B1Dynamic light-scattering measuring apparatus and method for measuring light-scattering intensity of particles in a medium
Publication Date: 2021.03.17 FUJIFILM CORP
  • EP2270449B1 patent drawingFigure 1
  • EP2270449B1 patent drawingFigure 2
  • EP2270449B1 patent drawingFigure 3

AI summary

There is provided a dynamic light-scattering measuring apparatus including: a Mach-Zehnder interferometer; and a low-coherence light source. Further, there is provided a method for measuring light-scattering intensity of particles in a medium, including the steps of: providing a Mach-Zehnder interferometer; and measuring light-scattering intensity from light emitted from a low-coherence light source, in accordance with a dynamic light-scattering intensity measuring process.