• 센서학회지
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• 제27권5호
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• pp.294-299
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• 2018

This article describes the output properties of non-dispersive infrared carbon dioxide($CO_2$) sensors resulting from the changes in ambient temperatures. After the developed sensor module was installed inside the gas chamber, the temperature was set to 267 K, 277 K, 300 K, and 314 K, and the concentrations of $CO_2$ gas were increased from 0 to 5,000 ppm. Then, the output voltage at each concentration was obtained. Through these experimental results, two observations were made. First, both the $CO_2$ sensor and the reference sensor showed an increase in the output voltages as the temperature rose from 0 ppm, Second, the full scale outputs of the $CO_2$ sensor grew as the temperature increased. The output characteristics were analyzed based on two factors: change in the radiant energy of the infrared light source and change in the absorptivity of $CO_2$ gas according to the ambient temperature. Additionally, temperature compensation methods were discussed.

• 인터넷정보학회논문지
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• 제14권2호
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• pp.45-51
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• 2013

본 논문에서는 자외선(UV, ultraviolet) 및 적외선(IR, infrared) 센서를 결합함으로서 불이 연소하면서 방출하는 빛의 파장을 활용한 영상신호를 검출하는 결합형 불꽃영상 검출시스템은 적외선 센서와 자외선 센서 기반의 신호처리 알고리즘 설계방안을 제안한다. 또한, 설계한 듀얼모드인 결합형 불꽃영상 검출시스템은 단독형 적외선 또는 자외선 센서 기반의 영상검출 알고리즘의 검출 성능결과를 비교한다.

• 항공우주산업기술동향
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• 제7권1호
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• pp.89-96
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• 2009

이 논문에서는 지구관측용 가시광선 및 적외선 위성센서의 검보정 방법들을 소개하였다. 먼저 지구관측용으로 쓰이는 위성용 센서들에 대해 간단히 살펴보고, 이들의 검보정 방법들을 정리하였다. 위성센서 중 특히 가시광선 및 적외선 광학센서의 보정장치들을 예로 들어 이들 장치의 원리에 대해서 간략하게 설명함으로써 센서레벨에서 이루어지는 1차적인 보정원리에 중점을 두었다.

• 세라미스트
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• 제21권2호
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• pp.59-74
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• 2018

Imaging in the Short Wave Infrared (SWIR) provides several advantages over the visible and near-infrared regions: enhanced image resolution in in foggy or dusty environments, deep tissue penetration, surveillance capabilities with eye-safe lasers, assessment of food quality and safety. Commercially available SWIR imagers are fabricated by integrating expensive epitaxial grown III-V compound semiconductor sensors with Si-based readout integrated circuits(ROIC) by indium bump bonding Infrared image sensors made of solution-processed quantum dots have recently emerged as candidates for next-generation SWIR imagers. They combine ease of processing, tunable optoelectronic properties, facile integration with Si-based ROIC and good performance. Here, we review recent research and development trends of various application fields of SWIR image sensors and nano-materials capable of absorption and emission of SWIR band. With SWIR sensible nano-materials, new type of SWIR image sensor can replace current high price SWIR imagers.

• 센서학회지
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• 제26권3호
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• pp.168-172
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• 2017

A nondispersive infrared (NDIR) ethanol gas sensor was prototyped with ASIC implemented thermopile sensor, which included a temperature sensor and two ellipsoidal waveguide structures. The temperature dependency of the two ethanol sensors (with partially blocked and intact structures) has been characterized. The two ethanol gas sensors showed linear output voltages initially when varying the ambient temperature from 253 K to 333 K. The slope of the temperature sensor presented a constant value of 15 mV/K. After temperature compensation, the ethanol gas sensor estimated ethanol concentrations with larger errors of 20 to 25% below 200 ppm. However, the estimation errors were reduced to between -10 and +1 % from 253 K to 333 K above 200 ppm ethanol gas concentration in this research.

• 센서학회지
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• 제25권2호
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• pp.124-130
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• 2016

NDIR $CO_2$ gas sensor was built with ASIC implemented thermopile sensor which included temperature sensor and unique elliptical waveguide structures in this paper. The temperature dependency of dual infrared sensor module ($CO_2$ and reference IR sensors) has been characterized and its output voltage characteristics according to the temperature and gas concentration were proposed for the first time. NDIR $CO_2$ gas and reference IR sensors showed linear output voltages according to the variation of ambient temperatures from 243 K to 333 K and their slopes were 14.2 mV/K and 8.8 mV/K, respectively. The output voltages of temperature sensor also presented a linear dependency according to the ambient temperature and could be described with V(T)=-3.191+0.0148T(V). The output voltage ratio between $CO_2$ and reference IR sensors revealed irrelevant to the changes of ambient temperatures and gave a constant value around 1.6255 with standard deviation 0.008 at 0 ppm. The output voltage of $CO_2$ gas sensor at zero ppm $CO_2$ gas consisted of two components; one is caused by the HPB (half pass-band) of IR filter and the other is attributed to the part of $CO_2$ absorption wavelength. The characteristics of output voltages of $CO_2$ gas sensor could be accurately modeled with three parameters which are dependent upon the ambient temperatures and represented small average error less than 1.5% with 5% standard deviation.

• 센서학회지
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• 제27권1호
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• pp.47-54
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• 2018

In this paper, we describe the thermal characteristics of the output voltages of ethanol gas sensor according to the amount of radiation incident on the infrared sensors located at each focal point of two elliptical waveguides. In order to verify the output characteristics of the gas sensor according to the amount of incident light on the infrared sensor, two combinations of sensor modules were fabricated. Hydrophobic thin film is deposited on one of the reflectors of sensor modules and one of the two infrared sensors was equipped with a hollow disk (10 Ø), and the temperature characteristics of the infrared sensor equipped with the hollow disk (10 Ø) and the infrared sensor without the disk were tested. The temperature was varied from 253 K to 333 K at 10 K intervals based on 298 K. The properties of ethanol gas sensor have been identified with respect to varying temperature for a range of ethanol concentration from 0 ppm to 500 ppm. In the case of an infrared sensor equipped with a hollow disk (10 Ø), the output voltage of the sensor decreased by 0.8 mV and 1 mV, respectively, as the temperature increased. Conversely, the output voltage of the diskless infrared sensor showed an average increase of 67 mV and 57 mV as the temperature increased. The ethanol concentrations estimated on the basis of results show an error of more than 10 % for less than 100 ppm concentration. However, if the ethanol concentration exceeds 100 ppm, the gas concentration can be estimated within the range of ${\pm}10%$.

• 한국기계가공학회지
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• 제4권4호
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• pp.34-38
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• 2005

This is a widespread requirement for low cost lightweight thermal imaging sensors for both military and civilian applications. Today, a large number of uncooled infrared detector developments are under progress due to the availability of silicon technology that enables realization of low cost IR sensor. System prices are continuing to drop, and swelling production volume will soon drive process substantially lower. The feasibility of micromechanical optical and infrared (IR) detection using microcantilevers is demonstrated. Microcantilevers provide a simple Structurefor developing single- and multi-element sensors for visible and infrared radiation that are smaller, more sensitive and lower in cost than quantum or thermal detectors. Microcantilevers coated with a heat absorbing layer undergo bending due to the differential stress originating from the bimetallic effect. This paper reports a micromachined silicon uncooled thermal imager intended for applications in automated process control. This paper presents the design, fabrication, and the behavior of cantilever for thermomechanical sensing.

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권2호
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• pp.73-76
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• 2004

0-3 PbTiO$_3$/P(VDF/TrFE) nanocomposite thin films for passive pyroelectric infrared sensors were fabricated by a two-step spin coating technique. 65wt% VDF and 35 wt% TrFE was formed into a P(VDF/TrFE) powder. Nano size PbTiO$_3$ powder was used. 0-3 connectivity of PbTiO$_3$/P(VDF/TrFE) composite film was successfully achieved and observed using SEM photography. The dielectric constant and pyroelectric coefficient were measured and compared with P(VDF/TrFE). A very low dielectric constant (13.48 at 1KHz and sufficiently high pyroelectric coefficient (3.101 nC/$\textrm{cm}^2$ㆍk at 5$0^{\circ}C$) were measured. This nanocomposite can be used for a new pyroelectric infrared sensor to achieve better performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.490-492
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• 2004

This paper presents an obstacle avoidance of a mobile robot by the subgoal generation using infrared sensors. When an obstacle appears on the path which the robot is moving forward the robot has to get information, such as distance between the robot and the obstacle and the shape of the obstacle for avoidance behavior. Our collision avoidance algorithm needs the only distance between the robot and the obstacles. The distances are used for subgoal generation. Simulation results show that a robot can go to the goal, carrying out subgoal generation and avoiding obstacles.