扫描型热像仪校正黑体的实时控温技术研究

Real-time temperature control technology for correcting blackbody by scanning thermal imager

扫描型热像仪采用实时控温的校正黑体获得最优的校正输出,而校正黑体温度的闭环控制目前采用的方法是通过探测器扫描黑体以获得反馈构成闭环控制系统。探测器扫描输出反馈信号的周期为20 ms,使得温控系统带宽受限,响应滞后,当场景辐射变化剧烈时,图像校正输出偏离,影响热像仪整机效能。为解决该问题现采用热敏铂电阻测温作为反馈信号去实现黑体控温,提高带宽,通过实际多个场景对比试验,验证热像仪的校正输出对场景的适应性更强。

Straining thermal imager use real-time temperalure-controlled blackbody to obtain the optimal corrected output. Using detectors in scanning blackbody to get feedback and forming closed-loop control systems are currently applied in correcting blackbody temperature closed-loop control. The period of the scanning feedback output of the detector is 20ms,which makes the bandwidth of the temperature control system linfited, and the response lags. When the scene radiation changes drastically, the image correction output deviates,which affects the overall performance of the thermal imager. In order to solve this problem,the thermal platinum resistance temperature measurement is used as the feedback signal to realize the blackbody temperature control and increase the bandwidth. Through the actual nmltiple scene comparison tests,it is verified that the correction output of the thermal imager is more adaptable to the scene.