• JSTS:Journal of Semiconductor Technology and Science
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• v.11 no.3
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• pp.221-228
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• 2011

This paper describes 250-Mb/s fiber optic transmitter and receiver ICs for plastic optical fiber applications using a$ 0.18-{\mu}m$ CMOS technology. Simple signal and light detection schemes are introduced for power reduction in sleep mode. The transmitter converts non-return-to-zero digital data into 650-nm visible-red light signal and the receiver recovers the digital data from the incident light signal through up to 50-m plastic optical fiber. The transmitter and receiver ICs occupy only 0.62 $mm^2$ of area including electrostatic discharge protection diodes and bonding pads. The transmitter IC consumes 23 mA with 20 mA of LED driving currents, and the receiver IC consumes 16 mA with 4 mA of output driving currents at 250 Mb/s of data rate from a 3.3-V supply in active mode. In sleep mode, the transmitter and receiver ICs consume only 25 ${\mu}A$ and 40 ${\mu}A$, respectively.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.5
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• pp.10-17
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• 1994

Two protocols inclouding the receiver collision avoidance function are proposed for high-speed optical fiber LANs with finite users. The basic idea to avoid receiver collision is the grouping of destination nodes by the number of channels and it is accomplished in the architecture with or without one separate control channel. While the protocol with a control channel requires a tunable optical transmitter, a fixed optical transmitter and two fixed optical receiver, the other protocol requires a tunable optical transmitter and one fixed optical receiver. The performance of two receiver collision avoidance protocols is computed and analyzed under various system parameters. The numerical results show that the receiver collision avoidance protocol has better performance for a small load than the protocol without receiver collision avoidance.

• Korean Journal of Optics and Photonics
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• v.28 no.2
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• pp.75-82
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• 2017

We present a new type of receiver-transmitter optical system that can be adapted to the sensor head of a displacement-measuring interferometer. The interferometer is utilized to control positioning error and repetition accuracy of a wafer, down to the order of 1 nm, in a semiconductor manufacturing process. Currently, according to the tendency of scale-up of wafers, an interferometer is demanded to measure a wider range of displacement. To solve this technical problem, we suggest a new type of receiver-transmitter optical system consisting of a GRIN lens-Collimating lens-Afocal lens system, compared to conventional receiver-transmitter using a single collimating lens. By adapting this new technological optical structure, we can improve coupling efficiency up to about 100 times that of a single conventional collimating lens.

• Journal of Korea Society of Industrial Information Systems
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• v.11 no.3
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• pp.82-89
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• 2006

Optical transmission system related to network infra of ubiquitous is a essential bridge technique between metro network and access point. So, it is need to develop this technique. In this paper, we develop 1Gbps SNMP optical transmitter/receiver system based on 1 core ring-type WDM PON. The developed system can reduce number of optic fiber and doesn't need extra transmitter/receiver. Also, this system can extend nodes owing to many node per wavelength, acts rapidly against security cutting, and acts independent of protocols.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1112-1115
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• 1990

Described is a new control signal transmission system which utilizes an optical fiber to transmit 2-bit control signals from the transmitter to receiver. In the transmitter the DC series control voltages are converted into the multiple frequency signals by voltage controlled oscillator (VCO). The multiple frequency signals can easily be transmitted by optical fiber. In the receiver the multiple frequency signals can be detected by analog or digital circuits and then be converted into 2-state control signals which can be used for a variety of applications.

• Proceedings of the Optical Society of Korea Conference
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• 2004.07a
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• pp.28-29
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• 2004

Optical wireless mobile communications have the potential to provide wide bandwidth and security . We have proposed and designed the 2-dimensional tracking optical receiver systems for optical wireless mobile communication. The receiver system consist of 4${\times}$4 photodiode array can receive optical signal from the transmitter. The room size is 5${\times}$5m$^2$ and the room height is 3m.

• Korean Journal of Optics and Photonics
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• v.13 no.4
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• pp.295-300
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• 2002

We developed an optical transmitter and receiver for an electrical time division multiplexed (ETDM) 20 Gb/s optical transmission system, and experimentally investigated their characteristics. Especially, the clock extraction circuit, which is a key component in realizing broadband optical transmission receivers, was realized by using an NRZ-to-PRZ converter implemented with a half-period delay line and an EX-OR, a high-Q bandpass filter using a cylindrical dielectric resonator, and a microstrip coupled-line bandpass filter. Finally, the bit-error-rate of demultiplexed 10 Gb/s electrical signal after back to-back transmission was measured, and a high receiver sensitivity [-26.2 dBm for NRZ ($2^{7}-1$) pseudorandom binary sequence (PRBS)] was obtained

• Korean Journal of Optics and Photonics
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• v.15 no.2
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• pp.158-170
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• 2004

Wireless optical communication is expected for high-speed optical communication in the areas of saturated optical fiber communication and low population density. In this paper, we present an optical transmitter system for wireless optical communication with new design concepts different from the usual optical imaging system. The specifications are the following: the source is a laser diode(LD) of wavelength 830 nm in which the divergent angle from the tangential plane differs from that from the sagittal plane. Here, the requested transmission distances are very long range such as 500 m to 1500 m and beam diameter is 3 m at the receiver with symmetrical energy distribution. For the evaluation characteristics of this kind of non-imaging system, two optical quantities, the relative illumination distribution and energy transfer efficiency, are numerically calculated through lots of ray tracing.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.3 no.1
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• pp.19-23
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• 2010

This study is to develop power line communication and short-range wireless communication system using LED. I will create optical receiver and transmitter using LED and optical sensor and connectors for display device and communication in receiver and transmitter were created. Experiment method is to signal and waveform through oscilloscope date from optical sensor after chosen a highly efficient LED. In addition, reception and transmitter of smoothly data using visible light communication program were checked. I will compliment problems through this experiment and constantly study, improve on power loss.

• Journal of Sensor Science and Technology
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• v.29 no.3
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• pp.180-186
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• 2020

In this study, we applied edge-pulse modulation to prevent the flicker of light-emitting diode (LED) light in a visible light identification system. In the visible light transmitter, positive pulses were transmitted at the edges of the low-to-high transition points, and negative pulses were transmitted at the edges of the high-to-low transition points of the non-return-to-zero (NRZ) data waveforms. In the visible light receiver, the NRZ waveforms were regenerated by making low-to-high and high-to-low transitions at the point of the positive and negative pulses, respectively. This method has two advantages. First, it ensures that the LED light is flicker-free because the average optical power of the LED was kept constant during data transmission in the transmitter. Second, the 120 Hz optical noise from the adjacent lighting lamps was easily cut off using a simple RC-high pass filter in the receiver.