Particle Counting Timer Logic for Flow Cell Boundary Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing particle counting methods inaccurately count particles near the inner wall of a flow cell or flow channel boundary, leading to false recognition of one particle as multiple particles or failure to count particles due to unstable behavior and signal waveforms with overshoot.
Innovation Solution
A particle counting method that compares the maximum output of a photoelectric conversion element to a preset threshold for each particle size range, utilizing a timer to accurately count particles by starting and extending a timer based on threshold changes, ensuring that each particle is counted as a single entity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If judgment is made only by the time when the output voltage exceeds a threshold or by the duration time of scattered light, then the counting process is simple, but one particle may be falsely recognized as a plurality of particles or particles may not be counted due to unstable behavior near flow channel boundaries
Solution Approach 1:
The patent applies preliminary action by comparing the sample value to the minimum particle size threshold before initiating the counting process. This preliminary comparison ensures that only signals meeting the minimum particle size criteria are processed further, preventing false recognition of noise or artifacts as particles while maintaining simple counting logic for valid particles.
Solution Approach 2:
The patent introduces an intermediary timer mechanism that bridges the simple threshold comparison and the final counting decision. The timer tracks the duration that the sample value exceeds the threshold, providing an intermediate verification step that distinguishes true particles (with sustained signals) from false positives (with transient signals), thereby improving counting accuracy without significantly increasing system complexity.
2Ease of operation
If judgment is made only by the time when the output voltage exceeds a threshold or by the duration time of scattered light, then the counting method is straightforward, but signal waveforms with overshoot cause one particle to be falsely recognized as multiple particles
Solution Approach 1:
The patent applies preliminary action by comparing the sample value to the minimum particle size threshold before initiating the counting process. This preliminary comparison ensures that only signals meeting the minimum particle size criteria are processed further, preventing false recognition of noise or artifacts as particles while maintaining simple counting logic for valid particles.
Solution Approach 2:
The patent introduces an intermediary timer mechanism that bridges the simple threshold comparison and the final counting decision. The timer tracks the duration that the sample value exceeds the threshold, providing an intermediate verification step that distinguishes true particles (with sustained signals) from false positives (with transient signals), thereby improving counting accuracy without significantly increasing system complexity.
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
Improves measuring accuracy by correctly counting particles exhibiting unstable behavior near the flow channel boundaries and large particles with overshoot signals as single entities, enhancing the reliability of particle size range counting.
Implementation Method 1
scattered light produced by causing the laser light to hit a particle in the fluid sample is detected by a photoelectric conversion element
Data Source
AI summary
A particle counting method is provided whereby a liquid sample is radiated by a laser light, scattered light produced by causing the laser light to hit a particle in the liquid sample is detected by a photoelectric conversion element, and a sample value which is the output of the photoelectric conversion element is sequentially compared to a threshold preset for each particle size range, thereby counting the number of particles for each particle size range, the method comprising: a timer start-up step for starting a timer of a predetermined time when the sample value becomes smaller than a threshold of a minimum particle size for the first time and for sequentially holding the maximum value of the sample value; and a timer extension step for restarting the timer to sequentially hold the maximum value of the sample value when the sample value at the time-out of the timer start-up step is larger than the threshold of the minimum particle size.