• Journal of Sensor Science and Technology
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• v.5 no.5
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• pp.63-68
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• 1996

In order to implement the integrated capacitive pressure sensors, which contains integrated interface circuits to detect the electrical output signal, several main factors that have a bad effect on the characteristics of sensors must be improved, such as parasitic capacitance effects, temperature/thermal drift, and the leakage current of a readout circuitry. This paper describes the novel design of the dedicated CMOS readout circuitry that is consists of two capacitance to frequency converters and 4 bit digital logic compensating circuits. Dividing the oscillation frequency of a sensing sensor by that of reference sensor, this circuit is designed to eliminate the thermal/temperature drift and the effect of the leakage currents, and to access a digital signals to obtain a high signal-to-noise(S/N)ratio. Therefore, the resolution of this circuit can be increased by increasing the number of the digital bits. Digital compensated circuits of this circuits, except for the C-F converters, are fabricated on a FPGA chip, and fundamental performance of the circuits are evaluated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.29-29
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• 2007

TFT, LCD, OLED, PDP and FED를 비롯한 많은 디스플레이 장치가 개발, 연구되고 있으며, 이러한 디스플레이 장치에 대한 수 많은 application 연구 또한 진행되고 있다. TFT-LCD는 이미 방사선 검출기로서 연구가 오랜전에 연구되어 상용화가 되었으며, LCD는 XLV로서 적용을 위한 연구가 진행되고 있으며, 그 외 수 많은 디스플레이 장치에 대한 활발한 연구가 진행되고 있는 실정이다. PDP는 대면적, 낮은 제작 비용, 높은 contrast의 이점으로 디스플레이 장치로서 활발한 연구가 진행되고 있다. 본 논문에서는 PDP를 처음으로 방사선 검출기로 적용하기 위한 연구를 수행하였다. 제작된 7 인치 AC-PDP는 다양한 가스종류 및 압력을 가진 300um의 pixel pitch룰 가진 3 전극 구조로서, coplanar readout과 대항형 readout을 통해 신호량을 분석하였다. 결과 50-100Kvp의 진단 영역의 X-ray energy에서 줄은 민감도와 훌륭한 선형성을 보였으며, 가스 종류 및 압력, 신호 검출방식에 따라 각각 다른 특성을 보였다. 이는 PDP 내 X선과의 Interaction, R/O method. Material에 강하게 의존한다.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.11
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• pp.36-43
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• 2015

A pixel-level readout circuit is studied for 2-dimensional microbolometer focal plane arrays (FPAs). A current mirroring injection (CMI) input circuit with 2-step current-mode bias suppression is proposed for a pixel-level architecture with high responsivity and long integration time. The proposed circuit has been designed using a $0.35-{\mu}m$ 2-poly 4-metal CMOS process for a $320{\times}240$ microbolometer array with a pixel size of $50{\mu}m{\times}50{\mu}m$. The proposed 2-step bias-current suppression has sufficiently low calibration error with wide calibration range, and the calibration range and error can be easily optimized by controlling some design parameters. Due to high responsivity and a long integration time of more than 1 ms, the noise equivalent temperature difference (NETD) of the proposed circuit can be improved to 26 mK, which is much better than that of the conventional circuits, 67 mK.

• Progress in Medical Physics
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• v.33 no.4
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• pp.72-79
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• 2022

Purpose: The proficiency test was conducted to assess the performance of the dosimetry audit service provider in the readout practice of the dose delivered to patients in medical institutions. Methods: A certain amount of the absorbed dose to water for the high-energy X-ray from the medical linear accelerator (LINAC) installed in the Korea Research Institute of Standards and Science (KRISS) was delivered to the postal dose audit package given by the dosimetry audit service provider, in which the radio-photoluminescence (RPL) glass dosimeters were mounted. The dosimetry audit service provider read the RPL glass dosimeters and sent the readout dose value with its uncertainty to KRISS. The performance of the dosimetry audit service provider was evaluated based on the E_n number given in ISO/IEC 17043:2010. Results: The evaluated E_n number was -0.954. Based on the ISO/IEC 17043, the performance of the dosimetry service provider is "satisfactory." Conclusions: As part of the conformity assessment, the KRISS performed the proficiency test over the postal dose audit practice run by the dosimetry audit service provider. The proficiency test is in line with confirming the traceability of the medical institutions to the primary standard of absorbed dose to the water of the KRISS and ensuring the confidence of the dosimetry audit service provider.

• Journal of Navigation and Port Research
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• v.35 no.9
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• pp.707-715
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• 2011

To propose an ergonomic layout on the bridge, this study conducted a usability evaluation on the on-bridge navigational equipment of a college training ship that is in use at present. Through the usability evaluation on the training ship navigators, the possibility of operational errors with navigational equipment, the possibility of readout errors with display devices and even the effect of navigational equipment on navigation were evaluated beyond the scope of existing layouts, which adopt only the importance and usage frequency of navigational equipment. By taking ergonomic variables into consideration, this study suggested an optimized layout for on-bridge navigational equipment using a mathematical programming model.

• Progress in Superconductivity
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• v.14 no.2
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• pp.87-91
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• 2012

Metallic magnetic calorimeters (MMCs) are one of the most competitive low temperature detector (LTD) readout sensors. They have the advantages of high time resolution, no heat dissipation, and a wide range of operating temperature. We apply MMCs to our neutrinoless double beta decay ($0v{\beta}{\beta}$) search experiment. A $CaMoO_4$ crystal was employed as both a source of $0v{\beta}{\beta}$ and an energy absorber. The crystal was thermally connected to a MMC sensor. We set a simple thermal model for this detector and measured pulse shapes are compared with a numerical solution of the thermal model.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.780-783
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• 2004

The two-dimensional modeling of the non-stationary thermal state and voltage responsivity of the sensitive elements usually used in solid-state pyroelectric focal plane arrays are presented. Temperature distributions under periodical thermal excitation and the response of the thermal imaging device, which is composed of the pyroelectric sensitive elements mounted on a single silicon substrate, are numerically calculated. The sensitive element consists of a covering metal layer, infrared polymer absorber, front metal contact, sensitive pyroelectric element, the interconnecting column and the bulk silicon readout. The results of the numerical modeling show that the thermal crosstalk between sensitive elements to be critical especially at low frequency (f < 10Hz) of periodically modulated light. It is also shown that the use of our models gives the possibility to improve the design, operating regimes and sensitivity of the device.

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.244-247
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• 2000

This paper deals with methods for partial response maximum-likelihood (PRML) detection and crosstalk cancellation. In accrodance with the demand for increased recording density, 20 gigabyte (Gbyte) digital versatile disk (DVD) ROM channel is considered. Channel is modelled to be close to real optical channel using DIFFRACT$\^$TM/. After comparing the spectral characteristics of various PR polynomials, P(D)=1＋D＋D$^2$＋D$^3$is proposed as a target PR. The performance of the system is illustrated under the condition that the readout signal is degraded by crosstalk, radial tilt and nonlinear distortions in optics. The experimental results show that crosstalk and nonlinear distortions degrade performance by about 2dB, respectively. We also show that when radial tilt is added to the crosstalk, the performance degradation assumes quite significant proprotions.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.647-650
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• 2005

In this paper, a low voltage SRAM using double boosting scheme is described. A low supply voltage deteriorates the static noise margin (SNM) and the cell read-out current. For read/write operation, a selected word line and cell VDD bias are boosted in a different level using double boosting scheme. This increases not only the static noise margin but also the cell readout current at a low supply voltage. A low voltage SRAM with 32K ${\times}$ 8bit implemented in a 0.18um CMOS technology shows an access time of 26.1ns at 0.8V supply voltage.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.7-8
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• 2009

In the presence of infrared light, a CMOS Readout IC (ROIC) for a microbolometer typed infrared sensor detects the voltage or current that is caused by the changing in resistance in the bolometer sensor. A serious problem in designing the ROIC is how the value of the bolometer and reference resistors vary because of variations in manufacturing process. Since different pixel have different, resistance values, sensor operations must contend with fixed pattern noise (FPN) problems. In this paper, we propose a novel technique to compensate for the fluctuation in reference resistance by tiling into account the process variation. By using constant current source basing and correlated double sampling, we solved FPN.