Luo Zhendong, Zhang Peng, Hou Huwang, Li Yiming, Li Binzhao, Yi Yanji, Xu Lianjie, Meng Ting, Geng Zihan, Chen Mu Ku, Zhao Yang
CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Precision Machinery and Instrumentation, University of Science and Technology of China, Hefei, 230026, China.
Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, 999077, China.
Adv Sci (Weinh). 2025 Jan;12(2):e2408683. doi: 10.1002/advs.202408683. Epub 2024 Nov 19.
Infrared (IR) radiation thermography is extensively utilized in diverse fields due to its non-contact capability. Nevertheless, its effectiveness is often compromised by the significant emissivity variations among different objects, limiting its application to specific setups or focused object types. Colorimetric thermography is introduced as an alternative emissivity-independent method of radiation thermometry. This technique involves measuring radiance across two or more spectral bands and calculating the object's temperature based on the signal ratio, thereby mitigating emissivity effects under certain conditions. However, this method has the trade-off of necessitating bulky optical systems, complex filter imaging configurations, and sensor structures. To meet the requirements of IR thermography for compact structure, lightweight design, and customizability, a dual-band metalens is developed for the IR colorimetric thermography. The central wavelengths targeted are 9.5 and 12.5 µm. The dual-band IR imaging by the fabricated dual-band metalens is demonstrated, and the colorimetric thermography of low-emissivity objects is performed without presetting emissivity values. This approach significantly eliminates measurement errors associated with emissivity by an average of 50.16% across a temperature range of 60-180 °C. This innovation paves the way for dynamic and multi-target thermography using compact IR systems in complex environments.
红外（IR）辐射热成像因其非接触能力而在多个领域得到广泛应用。然而，不同物体之间显著的发射率变化常常会影响其效果，限制了它在特定设置或特定类型物体上的应用。比色热成像作为一种与发射率无关的辐射测温替代方法被引入。该技术涉及测量两个或更多光谱波段的辐射率，并根据信号比计算物体的温度，从而在一定条件下减轻发射率的影响。然而，这种方法的权衡之处在于需要庞大的光学系统、复杂的滤光器成像配置和传感器结构。为满足红外热成像对紧凑结构、轻量化设计和可定制性的要求，开发了一种用于红外比色热成像的双波段超构透镜。其目标中心波长为9.5微米和12.5微米。展示了由制造的双波段超构透镜进行的双波段红外成像，并在不预设发射率值的情况下对低发射率物体进行了比色热成像。这种方法在60至180摄氏度的温度范围内平均显著消除了与发射率相关的测量误差，消除率达50.16%。这一创新为在复杂环境中使用紧凑红外系统进行动态和多目标热成像铺平了道路。
