Dual-Field Radiation Thermometer for Background IR Interference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radiation thermometers struggle to accurately measure the temperature of a target region when non-target objects or background objects emit infrared rays that interfere with the measurement, leading to inaccuracies, especially when the target region has low emissivity or is partially obscured.
Innovation Solution
The use of two infrared detectors with different measurement visual fields and/or detectable infrared wavelength bands or reflectance settings to cancel out the effects of non-target objects by calculating the target region's temperature based on the ratios and amounts of infrared rays detected by each detector.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a single infrared detector is used to measure temperature, then the device is simple and easy to operate, but the measurement accuracy deteriorates when non-target objects emit infrared rays
Solution Approach 1:
The patent divides the measurement system into multiple infrared detectors (first and second infrared detectors) with different measurement visual fields. The first infrared detector measures the measurement target region, while the second infrared detector measures a region including both the measurement target and non-target objects. This segmentation allows the system to separate and eliminate the effects of non-target objects from the measurement, thereby maintaining ease of operation while improving measurement accuracy.
2Measurement precision
If the measurement visual field is narrowed to include only the measurement target region, then measurement accuracy improves, but the device cannot meet demands for small or deep hole targets
Solution Approach 1:
The patent employs multiple infrared detectors with different measurement visual fields to segment the measurement coverage. The first infrared detector provides a narrowed visual field for high accuracy measurement of the target region, while the second infrared detector provides a broader visual field that includes non-target objects. This segmentation enables the system to adapt to various measurement scenarios, including small or deep hole targets, while maintaining measurement accuracy through the first detector's focused measurement.
3Reliability
If infrared rays from the background pass through the measurement target region, then the measurement is unaffected by background temperature, but the accuracy deteriorates when the target has low emissivity
Solution Approach 1:
The patent converts the harmful effect of background infrared rays passing through the measurement target into a beneficial measurement opportunity. By using the second infrared detector to measure a region including both the target and background, and by having the temperature calculator eliminate the effects of non-target objects, the system can accurately measure the target temperature even when background rays pass through low emissivity targets. The background radiation, which would normally be a source of error, becomes part of the measurement data that can be processed to obtain accurate target temperature.
4Measurement precision
If manual adjustment of optical system is performed to narrow the visual field, then measurement accuracy improves, but time and effort for adjustment increase
Solution Approach 1:
The patent segments the measurement function into multiple fixed infrared detectors with predetermined measurement visual fields, eliminating the need for manual optical adjustment. The first infrared detector is pre-configured to measure the measurement target region, and the second infrared detector is pre-configured to measure a region including non-target objects. This segmentation with fixed configurations provides measurement accuracy without requiring time-consuming manual adjustment, as the appropriate detector is simply selected based on the measurement requirements.
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
This configuration allows for accurate temperature measurement of the target region, unaffected by temporal changes or positional gradients of non-target objects, even when they emit or reflect infrared rays.
Implementation Method 1
receives infrared rays emitted from a measurement target region by an infrared sensor (e.g., a thermopile) and measures the temperature of the measurement target region using the amount of received infrared rays
Implementation Method 2
distances between the respective infrared detectors and the measurement target region are set to be equal to each other, and the viewing angles of the respective infrared detectors are set to be different from each other
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A radiation thermometer 100 includes two infrared detectors 1 and 1' and a temperature calculator 2. The infrared detectors 1 and 1' each have a predetermined measurement visual field and detect the amount of infrared rays incident from the measurement visual field. The temperature calculator 2 calculates the temperature of a measurement target region Xa based on the amounts of infrared rays detected by the respective infrared detectors 1 and 1'. The measurement target region Xa is included in the measurement visual fields of the respective infrared detectors 1 and 1', and the sizes of the respective measurement visual fields are set to be different from each other with respect to the measurement target region Xa.