Machine-Vision-Driven Microarray Passive Temperature Sensor Inspired by Insect Compound Eyes for Wide-Range and High-Precision Surface Mapping

Real-time, accurate, and passive temperature monitoring is critical for industrial and scientific applications. However, conventional temperature sensors often require external power, rely on complex instrumentation, and may perturb the thermal field, compromising measurement accuracy in passive sensing scenarios. Although thermochromic materials offer visual and passive temperature feedback, their utility is limited by narrow sensitivity ranges and subjective interpretation. To address these challenges, this study introduces a machine-vision-enabled microarray passive temperature sensor (MAPTS) inspired by the cooperative perception mechanism of insect compound eyes. The system comprises arrays of organic thermochromic materials patterned via soft lithography on flexible, thermally conductive substrates, enabling wide-range passive thermal sensing. A deep learning-based ResNet-34 architecture deciphers the color-to-temperature relationship from optical images, facilitating high-precision, noncontact regression-based temperature prediction. Experimental results demonstrate that the MAPTS achieves dynamic thermal responses across 0-70 °C with a rapid prediction time of 50 ms. In a high-density 7 × 7 array configuration, the system exhibits better extrapolation performance (R² = 0.9996) and higher prediction accuracy (mean absolute error ≤ ±0.3 °C), compared to conventional thermochromic sensing methods. This work presents a cost-effective, highly accurate, and reliable approach for intelligent temperature monitoring in diverse applications.