• Journal of IKEEE
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• v.22 no.4
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• pp.907-915
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• 2018

This paper proposes a method to improve the performance of low cost infrared distance sensor. Infrared distance sensor measures the intensity of reflected light and converts it into distance. The proposed method improves the sensing distance of the sensor and makes it operate robustly in various lighting environments. This is achieved by extracting the characteristic curves of the sensor and applying the HDR (High Dynamic Range) technique. The output value of the sensor was obtained by varying the intensity of the infrared input and the exposure time, and the characteristic curve of the sensor was extracted from it.

• Journal of Industrial Technology
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• v.29 no.A
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• pp.77-82
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• 2009

In this paper, we implement a virtual keyboard using infrared distance sensor. A virtual keyboard allows a user to enter characters by selecting keyboard layouts with sensing areas. By projecting infrared light on any flat surface and detection devices we can sense the user's input characters. Unlike a conventional physical keyboard, the virtual keyboard provides convenience in terms of mobility, portability, and space savings.

• Journal of Sensor Science and Technology
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• v.20 no.2
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• pp.114-117
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• 2011

A thick 25 ${\mu}m$ thickness poled P(VDF/TrFE) film pyroelectric infrared ray sensor has been fabricated and then thin 1.6 ${\mu}m$ thickness P(VDF/TrFE) film pyroelectric infrared ray sensor has been fabricated also. These thick and thin P(VDF/TrFE) film pyroelectric infrared ray sensor was mounted in TO-5 housing to detect infrared light of 5.5 ~ 14 ${\mu}m$ wavelength for human body detecting with each other. The noise output voltage of the thick P(VDF/TrFE) film pyroelectric infrared ray sensor were 380 mV and NEP(noise equivalent power) is $3.95{\times}10^{-7}$ W which is the similar value with the commercial pyroelectric infrared ray sensor using ceramic materials as a sensing material. The NEP and specific detectivity $D^*$ of the thin P(VDF/TrFE) film pyroelectric infrared ray sensor were $2.13{\times}10^{-8}$ W and $9.37{\times}106$ cm/W under emission energy of 13 ${\mu}W/cm^2$ respectively. These result caused by lower thermal diffusion coefficient of a thin 1.6 ${\mu}m$ thickness PVDF/TrFE film than the thick 25 ${\mu}m$ thickness poled P(VDF/TrFE) film pyroelectric infrared ray sensor.

• Current Optics and Photonics
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• v.7 no.2
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• pp.200-206
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• 2023

Near-infrared (NIR) sensing technology using CMOS image sensors is used in many applications, including automobiles, biological inspection, surveillance, and mobile devices. An intuitive way to improve NIR sensitivity is to thicken the light absorption layer (silicon). However, thickened silicon lacks NIR sensitivity and has other disadvantages, such as diminished optical performance (e.g. crosstalk) and difficulty in processing. In this paper, a pixel structure for NIR sensing using a stacked CMOS image sensor is introduced. There are two photodetection layers, a conventional layer and a bottom photodiode, in the stacked CMOS image sensor. The bottom photodiode is used as the NIR absorption layer. Therefore, the suggested pixel structure does not change the thickness of the conventional photodiode. To verify the suggested pixel structure, sensitivity was simulated using an optical simulator. As a result, the sensitivity was improved by a maximum of 130% and 160% at wavelengths of 850 nm and 940 nm, respectively, with a pixel size of 1.2 ㎛. Therefore, the proposed pixel structure is useful for NIR sensing without thickening the silicon.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.4
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• pp.93-100
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• 1998

Pyoelectric infrared detectors based on La-modified PbTiO3 (PLT) thin films have been fabricated by RF magnetron sputtering and micromachining technology. The detectors form Pb$_{1-x}$ La$_{x}$Ti$_{1-x}$ O$_{3}$ (x=0.05) thin film ferroelectric capacitors epitaxially grown by RF magnetron sputtering on Pt/MgO (100) substrate. The sputtered PLT thin film exhibits highly c-axis oriented crystal struture that no poling trealization for sensing applications is required. This is an essential factor to increase the yield for realization of an infrared image sensor. Micromachining technology is used to lower the thermal mass of the detector by giving maximum sensor efficiency. Polyimide is coated on top of the sensing elements to support the fragile structure and the backside of the MgO substrate is selectively eteched to reduce the heat loss. The sensing element exhibited a very high detectivity D* of 8.5*10$^{8}$ cm..root.Hz/W at room temperature and it is about 100 times higher than the case of micromachining technology is not used. a sensing system that detects the position as well as the existence of a human body is realized using the array sensor.sor.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.8
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• pp.1461-1465
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• 2007

A micromachined sensor part for an infrared focal plane array has been designed and fabricated. Amorphous silicon was adapted as a sensing material, and silicon nitride was used as a membrane material. To get a good efficiency of infrared absorption, the sensor was made as a ${\lambda}/4$ cavity structure. All the processes were done in $0.5\;{\mu}m$ iMEMS fab. in the Electronics and Telecommunication Research Institute (ETRI). The processed MEMS sensor structure had a small membrane deflection less than $0.3\;{\mu}m$. This excellent deflection property can be attributed to the rigorous balancing of the stresses of individual layers. The efficiency of infrared absorption was more than 75% in the wavelength range $8\;-\;14\;{\mu}m$.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.115-118
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• 2000

Uncooled pyroelectric infrared detectors based on BST(B $a_{-x}$S $r_{x}$Ti $O_3$) thin films have been fabricated by RF magnetron sputtering and surface Micromachining technology. The detectors form BST thin film ferroelectric capacitors grown by RF magnetron sputtering on N/O/N(S $i_3$ $N_4$/ $SiO_2$/S $i_3$ $N_4$) membrane. The sputtered BST thin film exhibits highly c-axis oriented crystal structure that no poling treatment for sensing applications is required. This is an essential factor to increase the yield for realization of an infrared image sensor. surface-Micromachining technology is used to lower the thermal mass of the detector by giving maximum sensor efficiency Gold-black is evaporated on top of the sensing elements used the thermal evaporator. fabricated uncooled pyroelectric infrared detectors is highly output voltage at the low temperature(1$^{\circ}C$).).).

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.5
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• pp.641-647
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• 2003

The use of infrared range-finder sensor as the environment recognition system for mobile robot have the advantage of low sensing cost compared with the use of other vision sensor such as laser finder CCD camera. However, it is not easy to find the previous works on the use of infrared range-finder sensor for a mobile robot because of the non-linear characteristic of that. This paper describes the error due to non-linearity of a sensor and the correction of it using neural network. The neural network consists of multi-layer perception and Levenberg-Marquardt algorithm is applied to learning it. The effectiveness of the proposed algorithm is verified from experiment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.8
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• pp.3079-3089
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• 2015

In this paper, a smart constrained application protocol (CoAP)-based gateway with a border router is proposed for home safety services to remotely monitor the trespass, fire, and indoor air quality. The smart CoAP gateway controls a home safety sensor node with a pyroelectric infrared motion sensor, a fire sensor, a humidity and temperature sensor, and a non-dispersive infrared CO2 sensor and gathers sensing data from them. In addition, it can convert physical sensing data into understandable information and perform packet conversion as a border router for seamless connection between a low-power wireless personal area network (6LoWPAN) and the Internet (IPv6). Implementation and laboratory test results verify the feasibility of the smart CoAP gateway which especially can provide about 97.20% data throughput.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.1
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• pp.129-136
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• 2016

A novel sensing system for standing and moving human body using PIR(pyroelectric infrared) sensor was development. The system consists of power supply, interface circuit of PIR sensor, small stepping motor, and digital control. The detecting principle for stop human body is detecting the human body when the stepping motor sticking the PIR sensor and the fresnel lens has rotated by 180 degree at six second and has stopped the motor for no detecting signal of human body. We developed control algorism for proposed the detection system. The experimentation shows that the detector system had detected length and angle were 6m and 30 degree against as standing and moving human body with $37^{\circ}C$.