Planar Core Temperature Sensor With Blood Perfusion Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for measuring core body temperature, such as conventional contact thermometry, infrared thermometry, radiowave thermometry, and thermometry based on heat flow, suffer from invasiveness, accuracy issues, health risks, energy consumption, and calibration challenges, with dual heat flow methods experiencing slow response times and lateral heat dissipation.
Innovation Solution
A core body temperature sensor with a planar sandwich structure of thermistor pairs across thermal insulators with differing resistances, combined with a means to measure blood perfusion, allows for accurate determination of core body temperature by correcting for skin blood flow and minimizing lateral heat dissipation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If dual heat flow method with vertical thermal insulator design is used, then core body temperature can be determined, but lateral heat dissipation occurs and response time is slow
Solution Approach 1:
The patent transitions from a vertical thermal insulator design to a planar thermal insulator design. This dimensional change eliminates the lateral heat dissipation pathway that existed in the vertical configuration, as heat now flows primarily in the vertical direction through the planar insulator layer, thereby reducing response time while maintaining measurement accuracy.
2Measurement precision
If external heater element is used in zero-heat flow method, then core temperature can be derived, but significant energy is consumed and burn risks increase
Solution Approach 1:
The patent removes the external heater element from the measurement system. Instead of using active heating to create zero heat flux conditions, the invention uses passive thermal insulation with thermistor pairs to measure temperature gradients, thereby eliminating the energy consumption and burn risks associated with external heating while maintaining measurement capability.
3Device complexity
If dual sensor method without temperature compensation is used, then device complexity is reduced, but accurate thermal resistance values are required for calculation
Solution Approach 1:
The patent employs thermistor pairs that automatically measure temperature gradients across the thermal insulator, providing self-compensating temperature data. This self-service mechanism eliminates the need for external temperature compensation devices while maintaining measurement accuracy, as the thermistors inherently track temperature variations at different points in the thermal pathway.
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 sensor provides improved accuracy, reduced response time, and enhanced comfort by using a planar design with thermal insulators of differing resistances and a blood perfusion measurement to correct for skin heat flow, enabling precise core body temperature readings.
Implementation Method 1
measuring a temperature gradient over a layer that is in contact with an outside surface, e.g. skin, of the body
Implementation Method 2
at least a first thermistor pair of opposing thermistors across a first thermal insulator and a second thermistor pair adjacent to the first thermistor pair
Implementation Method 3
a means to measure blood perfusion. By measuring blood perfusion a disturbing contribution of heat flow due to skin blood flow on the total heat flow (flux) through the sensor may be determined
Data Source
Figure 1A~1C
Figure 2A~2C
Figure 3A~3B
AI summary
The present disclosure concerns a core body temperature sensor for measuring the core body temperature of a body in a non-invasive way via applying the core body temperature sensor to a surface of the bod. The core body temperature sensor comprises: at least a first thermistor pair of opposing thermistors across a first thermal insulator and a second thermistor pair, adjacent to the first thermistor pair, of opposing thermistors across a second thermal insulator, and a means to measure blood perfusion. The core body temperature sensor is an essential planar sandwich structure formed of the at least first and second thermistor pairs across the respective first and second thermal insulators sandwiched between opposing carriers. The present disclosure further concerns a method for determining a core body temperature and a method for the manufacturing of a core body temperature sensor.