Structured Dark-Beam Optics for Low-Concentration Particle Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing particle size and concentration measurement techniques face challenges in accurately measuring small particles at low concentrations due to limitations in sensitivity and dynamic range, particularly in the sub-micron range, where Gaussian laser beams result in low interaction rates and inaccurate size and concentration measurements.
Innovation Solution
The use of a structured dark beam with an anamorphic profile, combined with dual or multi-path detection and polarization techniques, enhances sensitivity and accuracy by increasing interaction rates and reducing noise, allowing for precise measurements down to 7 nm and below.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a smaller focused spot is used to measure smaller particles, then size resolution is improved, but the focus volume decreases and interaction rate with particles drops
Solution Approach 1:
The detection system is divided into multiple independent detection paths (dual-path or multi-path configuration), where each path contains its own detector. This segmentation allows the system to maintain a small focused spot for high size resolution while compensating for the low interaction rate by having multiple detection channels that can independently detect particles, thereby increasing the overall detection probability and interaction rate.
2Quantity of substance
If a larger focused spot is used to improve concentration measurement rate and accuracy, then concentration measurement is improved, but size analysis quality and resolution degrade
Solution Approach 1:
The system segments the detection function across multiple paths, where each path processes signals independently. This allows the use of a larger focused spot that improves concentration measurement by increasing the interaction volume and particle interaction rate, while the segmented detection architecture maintains size analysis resolution by ensuring that each detection path can still resolve individual particle events with sufficient precision.
Solution Approach 2:
The invention transitions from single-point detection to multi-point detection by implementing dual or multi-path detection configurations. This dimensional expansion in the detection space allows the system to simultaneously achieve large interaction volume (for concentration accuracy) and maintain size resolution by distributing detection capabilities across multiple spatial paths.
3Ease of manufacture
If conventional Gaussian laser beams are used for particle detection, then the system is simple to implement, but sensitivity and detection accuracy for small particles at low concentrations is limited
Solution Approach 1:
The invention changes the fundamental parameter of the laser beam from a conventional Gaussian profile to a structured dark beam profile. This parameter change in beam structure dramatically improves detection sensitivity for small particles at low concentrations by creating a dark background that enhances the visibility of particle scattering events, while the overall system implementation remains relatively simple by building upon conventional laser detection architectures.
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 system provides accurate particle size and concentration measurements in low concentrations, maintaining high sensitivity and resolution, suitable for clean liquids and gases in industries like semiconductor and pharmaceutical, and enabling rapid detection of small particles on surfaces.
Implementation Method 1
The use of optical methods for measuring particle size and concentration, and achieving an improved detection sensitivity or improved characterization of the measured particles
Implementation Method 2
at least one optical detector array in optical communication with the flow cell and the optical source; wherein the optical source directs the beam electromagnetic radiation to the optical lens thereby generating the anamorphic beam, wherein the portion of the anamorphic beam directed through the flow cell is provided to the at least one optical detector array which measures an interaction between the portion of the anamorphic beam and particles present in the flow cell
Implementation Method 3
a beam shaping optical system for receiving the beam of electromagnetic radiation; the beam shaping optical system for generating an anamorphic beam and directing at least a portion of the anamorphic beam through the flow cell
Implementation Method 4
combined with dual or multi-path detection and polarization techniques, enhances sensitivity and accuracy by increasing interaction rates and reducing noise
Data Source
AI summary
An optical system for particle size and concentration analysis, includes: at least one laser that produces an illuminating beam; a focusing lens that focuses the illuminating beam on particles that move relative to the illuminating beam at known or pre-defined angles to the illuminating beam through the focal region of the focusing lens; and at least two forward-looking detectors, that detect interactions of particles with the illuminating beam in the focal region of the focusing lens. The focusing lens is a cylindrical lens that forms a focal region that is: (i) narrow in the direction of relative motion between the particles and the illuminating beam, and (ii) wide in a direction perpendicular to a plane defined by an optical axis of the system and the direction of relative motion between the particles and the illuminating beam. Each of the two forward-looking detectors is comprised of two segmented linear arrays of detectors.