Ion Concentration Measurement Device with Time-Division RFID

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Solution Overview

Problem

Ion concentration measurement devices using ion selective electrodes face accuracy degradation due to radio waves generated during IC tag information reading and writing, which interfere with the measured potential difference.

Innovation Solution

The implementation of a semi-active RFID tag that only responds with radio waves when receiving a certain level of signal, avoiding overlap with potential difference measurement timing, and using electromagnetic induction or specific frequency bands for communication to minimize interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of information

If an IC tag is mounted on the cartridge for information storage and reading/writing, then device information recording capability is improved, but measurement accuracy deteriorates due to radio wave interference

Engineering Contradiction:
Improvedevice information recording capabilityVSAvoidpotential difference measurement accuracy
Core Design Contradiction:
Loss of informationVSMeasurement precision

Solution Approach 1:

The patent implements periodic action by sequentially alternating between measurement periods and communication periods. During the measurement period, the potential difference is measured without radio wave interference. During the communication period, information is read from or written to the IC tag using radio waves. This time-division approach ensures that the high-impedance electrode measurements are not contaminated by electromagnetic interference from RFID communication, while still enabling complete information storage and retrieval functionality.

Inventive Principle:
Principle #19Periodic action

2Measurement precision

If the electrode impedance is high to enable sensitive ion concentration measurement, then measurement sensitivity is improved, but radio wave interference from IC tag communication increases

Engineering Contradiction:
Improveion concentration measurement sensitivityVSAvoidradio wave interference
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent implements periodic action by sequentially alternating between measurement periods and communication periods. During the measurement period, the potential difference is measured without radio wave interference. During the communication period, information is read from or written to the IC tag using radio waves. This time-division approach ensures that the high-impedance electrode measurements are not contaminated by electromagnetic interference from RFID communication, while still enabling complete information storage and retrieval functionality.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The patent applies the extraction principle by separating the measurement function and communication function into distinct time periods. The harmful radio wave interference is extracted from the measurement process by performing communication operations only during designated communication periods when measurement is not occurring. This isolation eliminates the interference problem while preserving both functionalities.

Inventive Principle:
Principle #2Taking out (Extraction)

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

Enables accurate ion concentration measurements without degrading the potential difference measurement accuracy, allowing for efficient recording and updating of device information on the IC tag without interfering with the measurement process.

Implementation Method 1

The ion concentration measurement device of this type measures the concentrations of various ions in a sample by measuring the difference between the potential observed in the ion selective electrode and the potential observed in the reference electrode (potential difference)

Methodology Applied
Scientific EffectIon selective electrode method:

Implementation Method 2

using electromagnetic induction or specific frequency bands for communication to minimize interference

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP3339849B1Ion concentration measurement device
Publication Date: 2021.03.10 HITACHI HIGH TECH CORP
  • EP3339849B1 patent drawingFigure 1A~1B
  • EP3339849B1 patent drawingFigure 1C
  • EP3339849B1 patent drawingFigure 2

AI summary

The separation between an ion concentration measuring time period and an information read/write time period is not considered in existing devices. Therefore, in the present invention, the time period for retrieving information from a semiconductor memory mounted in a cartridge and the time period for measuring the concentration of ions are controlled so as not to overlap each other.