A team of researchers from Chuo University and Tokyo Institute of Technology has unveiled a cutting-edge, slimmer, and more efficient non-destructive image sensor that is set to revolutionize material-identification technologies, particularly in the ultrabroad millimeter-wave (MMW)–infrared (IR) bands. This breakthrough, published online on February 20, 2025, in Small Science, addresses longstanding technical challenges faced by photo-thermoelectric (PTE) sensors.
Traditionally, PTE sensors have been limited by the use of a single material channel, which restricts their performance by not fully utilizing their fundamental parameters. The new sensor, developed by Assistant Professor Kou Li and his team, offers a hybrid structure combining bismuth composite (Bicom) thermoelectric electrodes with carbon nanotube (CNT) film photo-thermal absorber channels. This innovative design significantly improves the sensor's performance by overcoming trade-offs between photo-absorptance and Seebeck coefficients.
Key Contributions of the Research:
- Hybrid Sensor Design: The sensor utilizes an effective hybrid combination of Bicom thermoelectric electrodes, known for their high Seebeck coefficient (>100 µV/K), and highly efficient CNT film absorber channels. This combination results in over ten times the response intensity compared to conventional single-material PTE detectors.
- Enhanced Performance: The hybrid PTE sensor meets the requirements for readable signal ranges, capable of achieving several millivolts in output—ideal for coupling with portable circuit modules. The sensor also outperforms existing wideband detectors in sensitivity, achieving a minimum noise equivalent power of 560 fWHz−1/2.
- Environmentally Robust: The sensor is designed to withstand extreme environmental conditions, such as high temperatures and cyclic deformations, while maintaining optical stability, making it suitable for practical, real-world applications.
- Non-Destructive Imaging: The team demonstrated the sensor’s capabilities in non-destructive imaging inspections, with potential uses in omni-directional, 3D target observations. Its easy-to-handle panoramic bowl camera module makes it ideal for a variety of testing scenarios.
The innovative sensor design marks a significant leap in the field of non-destructive testing, particularly for industries that require accurate material analysis and inspection. The team’s breakthrough sets a new standard for PTE sensors, making them more versatile and efficient for real-world applications.
"This work combines advanced material science with practical design principles, paving the way for more effective non-destructive testing in diverse industries," said Kou Li, Assistant Professor at Chuo University.
The research was conducted by a collaborative team of experts from Chuo University and Tokyo Institute of Technology, including Master’s course student Yuto Matsuzaki, and Bachelor’s students Reiji Tadenuma and Yuto Aoshima, among others. The successful demonstration of this sensor is expected to drive future developments in the field, particularly in areas requiring high-sensitivity, non-destructive material identification.
For more information on the research, visit the Small Science publication or reach out to the research team at Chuo University.
Reference: https://www.miragenews.com/slimmer-non-destructive-image-sensor-unveiled-1414403/
