• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.9
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• pp.11-17
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• 2006

We have theoretically investigated the effects of the interplay between the driving voltage of Mach-Zehnder(MZ) modulators and the bandwidth of low-pass filters(LPF) in 10[Gb/s] duobinary modulation systems. For the change of driving voltage ratios(driving voltage/switching voltage), the transmission performance has been evaluated over 200[km] of single-mode fiber(SMF) systems. For driving voltage ratios with smaller than 100[%], the transmission performance has been maintained and greatly affected by the bandwidth of LPFs than the driving voltage. For driving voltage ratios with larger than 100[%], the transmission performance has been degraded and is not sensitive to the bandwidth of LPFs. To see the limitation of driving voltage, we have reduced the driving voltage ratio to 50[%]. Our results suggest that 10[Gb/s] duobinary signals with driving voltage ratio with smaller than 100[%] have been transmitted over 200[km] SMF within 2[dB] power penalty without dispersion compensation. For the driving voltage ratio with 50[%], we have verified that the transmission performance was maintained.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.3
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• pp.1-7
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• 2008

We have theoretically investigated the asymmetry effects on 10[Gb/s] optical duobinary transmitters from the viewpoint of the driving voltage ratios by computer simulations. For driving voltage ratios(=driving voltage/switching voltage) with smaller than 100[%], the transmission performance has been greatly affected by the asymmetry of the bandwidth of LPFs than that of the Mach-Zehnder Modulator driving voltage. On the other hand, for driving voltage ratios with 100[%], the transmission performance has been degraded by the asymmetry of the driving voltage and is not sensitive to that of the bandwidth of LPFs. For the transmission performance within 1[dB] power penalty under the asymmetry condition, the driving voltage ratio with 100[%] has performed better than the low driving voltage ratios.

• KIEE International Transactions on Electrophysics and Applications
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• v.2C no.5
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• pp.253-257
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• 2002

A new Current-Controlled Driving Method that can drive AC PDPs with low voltage and high luminous efficiency for the sustaining period is presented. In this driving method, the voltage source is connected to a storage capacitor and the stored voltage is delivered to the panel through LC resonance. Thus, this driving method can drive the panel with a voltage source as low as about half of the voltage necessary in the conventional driving methods. The discharge current flowing into the AC PDP is limited in this method. Thus, the power consumption for the discharge is reduced and the discharge input power to output luminance efficiency is improved. Experimental results using this driving method showed that we could drive an AC PDP with a voltage source as low as 146V and that high luminous efficiency of 1.33 1m／W can be achieved.

• KIEE International Transactions on Electrophysics and Applications
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• v.2C no.6
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• pp.292-296
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• 2002

A new sustain driving method for the AC PDP is presented. In this driving method, the voltage source is connected to a storage capacitor, this storage capacitor charges an intermediate capacitor through LC resonance, and the panel is charged from the intermediate capacitor indirectly. In this way, the current flowing into the AC PDP when the sustain discharge occurs is reduced because the current is indirectly supplied from a capacitor, a limited source of charge. Thus, the input power to the output luminance efficiency is improved. Since the voltage supplied to the storage capacitor is doubled through LC resonance, this method call drive an AC PDP with a voltage source of about half of the voltage necessary in the conventional driving methods. The experiments showed that this charge-controlled driving method could drive ail AC PDP with a voltage source of as low as 107V. Using a panel of the conventional structure, luminous efficiency of 1.28 lm/W was achieved.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.11
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• pp.9-14
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• 2008

This paper presents the performance analysis of 10[Gb/s] optical duobinary transmitters with the non-ideal Mach-Zehnder modulator which does not have exactly 50/50 splitting/combining ratios by computer simulations. For driving voltage ratios(=driving voltage/switching voltage) with smaller than 100[%], the transmission performance has been greatly affected by extension of LPF bandwidths. Nevertheless, the performance has been degraded when the driving voltage ratio is 100[%]. The smaller driving voltage ratios has, the more sensitivity improves by extension of LPF bandwidths under the asymmetry condition. But the driving voltage ratio with 80[%] has better bit error rate(BER) than those with 50[%] and 25[%].

• Korean Journal of Materials Research
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• v.32 no.7
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• pp.320-325
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• 2022

Single OLED and tandem OLED was manufactured to analyze the electroluminescence characteristics of DC driving, AC driving, and full-wave rectification driving. The threshold voltage of OLED was the highest in DC driving, and the lowest in full-wave rectification driving due to an improvement of current injection characteristics. The luminance at a driving voltage lower than 10.5 V (8,534 cd/m²) of single OLED and 20 V (7,377 cd/m²) of a tandem OLED showed that the full-wave rectification drive is higher than that of DC drive. The luminous efficiency of OLED is higher in full-wave rectification driving than in DC driving at low voltage, but decrease at high voltage. The full-wave rectification power source may obtain higher current density, higher luminance, and higher current efficiency than the AC power source. In addition, it was confirmed that the characteristics of AC driving and full-wave rectification driving can be predicted from DC driving characteristics by comparing the measured values and calculated values of AC driving and full-wave rectification driving emission characteristics. From the above results, it can be seen that OLED lighting with improved electroluminescence characteristics compared to DC driving is possible using full-wave rectification driving and tandem OLED.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.1
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• pp.93-97
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• 2009

We analyzed voltage characteristics of toner particle type display according to particle layers and cell gap between two electrodes and ascertained the aging effects by measuring the response time of particles with and without aging process. The threshold/driving/breakdown voltage is proportional to layers of toner particles and cell gap and the response time at driving voltage is faster than that of threshold and breakdown voltage because of different q/m of color and black particles. The analysis of response time is a method of estimation of optical characteristics, driving voltage and particle lumping and these results are promoted by aging process. We use the laser and photodiode to measure response time and optical properties. It has not been studied and reported to analyze the relationship of response time, threshold/driving/breakdown voltage, lumping phenomena, cell gap, and aging process for toner particle type display.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.99-102
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• 1999

In recent years, attempts have been made to greatly improve the display quality of active-matrix liquid crystal display devices, and many techniques have been proposed to solve such problems as gate signal delay, feed-through voltage and image sticking. To improve these problems which are caused by the fried-through voltage, we have evaluated new driving methods to reduce the fled-through voltage. Two level gate-pulse was used for the gate driving of the cst-on-common structure pixels. And two-gate line driving methods with the optimized gate signals were applied for the cst-on-gate structure pixels. These gate driving methods were better feed-through characteristics than conventional simple gate pulse. The evaluation of the suggested driving methods were performed by using a TFT-LCD array simulator PDAST which can simulate the gate, data and pixel voltages of a certain pixel at any time and at any location on a TFT array. The effect of the new driving method was effectively analyzed.

• Progress in Superconductivity and Cryogenics
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• v.14 no.3
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• pp.43-47
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• 2012

A linear compressor generates pulsating pressure and oscillating flow in a cryocooler such as Stirling cryocooler and pulse tube refrigerator. It is driven by AC power source and designed to operate at resonance of piston motion. The driving voltage level is determined by electric parameters of resistance, inductance and thrust constant of linear motor. From voltage equation on linear motor, the power factor of driving power is inherently less than 1. The phase difference between voltage and current of supplied power can be zero using capacitor and this can minimize a supply voltage level. Especially, the linear compressor of kW class requires high voltage and thus can cause a difficulty in selecting power supply unit due to limitation of voltage level. The capacitor in driving electric circuit is useful to settle this problem. In this study, the electric circuit of linear compressor is analytically investigated with assumption of mechanical resonance. The electric parameters of commercial linear motor are used in the analysis. The effects of capacitor on driving voltage level and power factor are investigated. From analytic results, it is shown that the voltage level can be mimized with using capacitor in driving electric circuit.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.3
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• pp.65-70
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• 2008

Capacitive position sensing with modulation technique is widely used in electrostatic actuator applications. To maximize the electrostatic force and the position-sensing gain, capacitors for driving and capacitors for sensing are shared, i.e, after applying the driving voltage with high-frequency modulating signals using op amps, the position is demodulated from the modulated signal. In high-voltage applications, however, low bandwidth of a high-voltage op amp hinders adding the high-frequency modulating signal to the driving voltage. In this paper, new and very simple driving and sensing method is proposed, in which the pulse-width modulated driving voltage eliminates the need of the high-frequency modulating signal for position sensing. This new algorithm is proved by the simulation results using Matlab/SIMULINK.