Rotatable Reflector for Millimeter Wave Imaging Calibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing millimeter wave/terahertz wave imaging apparatuses have low working efficiency and unreliable calibration due to random temperature changes caused by airflow, which affects channel consistency in focal plane array systems.
Innovation Solution
A millimeter wave/terahertz wave imaging apparatus with a quasi-optical assembly and a detector array, where a rotatable reflector converges and reflects millimeter wave/terahertz waves from inspected objects onto the detector array, and a calibration source within the system provides stable calibration data to update image data in real-time, ensuring channel consistency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a rotatable reflector is used to simultaneously image multiple objects, then productivity is improved, but device complexity increases
Solution Approach 1:
The rotatable reflector serves multiple functions: it can simultaneously image multiple objects (first inspected object and second inspected object) by rotating to different positions, and it also serves as a calibration target when positioned at the calibration area. This multi-functionality improves productivity without requiring separate imaging systems for each object.
Solution Approach 2:
The reflector is designed to be rotatable rather than fixed, allowing it to dynamically change its orientation to face different inspection objects or the calibration source. This dynamic capability enables the system to efficiently switch between imaging multiple objects and performing calibration, improving overall detection efficiency.
2Device complexity
If remote air calibration is used, then device complexity is reduced, but reliability deteriorates due to temperature fluctuations
Solution Approach 1:
A calibration source is introduced as an intermediary element between the detector array and the environment. This calibration source acts as a stable reference that mediates the calibration process, providing consistent reference signals regardless of external temperature fluctuations or airflow conditions, thereby improving calibration reliability.
Solution Approach 2:
The calibration source is integrated into the system itself rather than relying on external environmental conditions. The system performs self-calibration by using its own built-in calibration source, which provides stable reference signals independent of external temperature changes or airflow, ensuring reliable calibration without requiring complex environmental control.
3Measurement precision
If all detector channels are calibrated in real-time, then measurement precision is improved, but loss of time increases
Solution Approach 1:
The calibration process is designed to be continuous and integrated with normal operation. The reflector can be rotated to the calibration area during regular scanning operations, and calibration data is continuously collected and used to maintain channel consistency. This continuous calibration approach ensures measurement precision without requiring separate calibration downtime.
Solution Approach 2:
The system uses feedback from the calibration source to continuously monitor and adjust detector channel consistency. By comparing signals from the calibration source across all channels, the system can identify and correct channel variations in real-time, maintaining measurement precision while minimizing calibration time through automated feedback mechanisms.
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 solution enhances detection efficiency and stability by allowing simultaneous imaging of multiple objects with improved channel consistency and reliable calibration, reducing the impact of temperature fluctuations.
Implementation Method 1
the reflector is rotatable about a horizontal axis to respectively receive and reflect a millimeter wave/terahertz wave from parts of the first inspected object at different vertical positions
Implementation Method 2
the quasi-optical assembly is configured to reflect a millimeter wave/terahertz wave radiated or reflected by a first inspected object and a second inspected object and converge the millimeter wave/terahertz wave onto the millimeter wave/terahertz wave detector array
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The present disclosure provides a millimeter wave/terahertz wave imaging apparatus, a method of detecting a human body or an article by using the millimeter wave/terahertz wave imaging apparatus, and a method of calibrating the millimeter wave/terahertz wave imaging apparatus. The millimeter wave/terahertz wave imaging apparatus includes a quasi-optical assembly and a millimeter wave/terahertz wave detector array. The quasi-optical assembly is adapted to reflect and converge a millimeter wave/terahertz wave radiated or reflected by a first inspected object and a second inspected object onto the millimeter wave/terahertz wave detector array. The quasi-optical assembly includes a reflector, and the first inspected object and the second inspected object are respectively located on opposite sides of the reflector. The reflector is rotatable about a horizontal axis so as to respectively receive and reflect a wave beam from parts of the first inspected object at different vertical positions of a first field of view and a wave beam from parts of the second inspected object at different vertical positions of a second field of view. The millimeter wave/terahertz wave detector array is adapted to receive a wave beam from the quasi-optical assembly. The imaging apparatus simultaneously images two inspected objects located on opposite sides of the reflector, thereby improving the inspection efficiency with a simple control and a low cost.