Department of Control & Instrumentation Engineering, Korea National University of Transportation (KNUT), 50 Daehakro, Chungjushi, Chungbuk 27469, Korea.
Department of Mechanical Engineering, Korea National University of Transportation (KNUT), 50 Daehakro, Chungjushi, Chungbuk 27469, Korea.
Sensors (Basel). 2018 Sep 1;18(9):2911. doi: 10.3390/s18092911.
This paper discusses the output characteristics of the sensor response of infrared ethanol gas detectors based on incident radiation intensity. Sensors placed at each focal point of two elliptical waveguides were fabricated to yield two module combinations and to verify the output characteristics. A thin Parylene-C film was deposited onto the reflector surfaces of one module. The thermal properties were compared between the sensor (2.0 Ø) and sensor with a hollow disk (1.6 Ø), the disk being mounted at the end of one detector. The fabricated sensor modules were placed inside a gas chamber. The temperature was increased from 253 K to 333 K, over the concentration range from 0 to 500 ppm. As the temperature increases by 10 K, the output of sensor (2.0 Ø) without and with Parylene-C coating typically increased by 70 mV and 52 mV, respectively. However, the sensor output with the hollow disk showed an average decrement of 0.8 mV/50 ppm and 1 mV/50 ppm for module without and with Parylene-C deposition, respectively. For concentrations higher than 50 ppm, the estimation error was around ±5%. Further, the sensitivity to temperature variation and the absorbance of infrared (IR) reflection was found higher for Parylene-C coated module.
本文讨论了基于入射辐射强度的红外乙醇气体探测器传感器响应的输出特性。在两个椭圆波导的每个焦点处放置传感器，以产生两种模块组合并验证输出特性。在一个模块的反射器表面沉积了一层薄的 Parylene-C 薄膜。在传感器（2.0Ø）和在传感器上安装有空心盘（1.6Ø）的传感器之间比较了热性能，该盘安装在一个探测器的末端。制造的传感器模块被放置在气体室内部。温度从 253 K 升高到 333 K，浓度范围从 0 到 500 ppm。随着温度升高 10 K，未涂覆和涂覆 Parylene-C 的传感器（2.0Ø）的输出分别典型地增加了 70 mV 和 52 mV。然而，带有空心盘的传感器输出对于没有和有 Parylene-C 沉积的模块，分别显示出平均减少 0.8 mV/50 ppm 和 1 mV/50 ppm。对于高于 50 ppm 的浓度，估计误差约为±5%。此外，发现涂覆有 Parylene-C 的模块对温度变化的敏感性和红外（IR）反射的吸收率更高。
