Abstract: A display device includes: a pixel defining layer defining openings arranged in first and second directions, the openings forming emission areas in which light emitting elements are disposed to emit light of different colors; a light blocking layer disposed on the pixel defining layer, and defining holes, each overlapping the opening and having a larger diameter than the opening; and color filters disposed on the light blocking layer to overlap the holes and overlap the emission areas. The opening has an opening interval, which is defined as a difference in diameter between the overlapping hole and the opening, in the openings, among homogeneous openings in which the light emitting elements for emitting light of the same color are disposed, the homogeneous openings adjacent in the first or second direction have different opening intervals, and among the homogeneous openings, openings having different opening intervals are at least three types.

Abstract: A complementary thin film transistor (TFT) includes a substrate and a first TFT and a second TFT disposed on the substrate, wherein a first conductive semiconductor layer of the first TFT and a second gate electrode layer of the second TFT are disposed in the same layer and include the same material.

Abstract: A bit rate-independent optical receiver ensures transparency with respect to changes of the transmission format and its associated bit rate in relation to an optical communications system. The optical receiver includes an opto-electric converter for converting an input optical signal into an electric signal, an amplifier circuit for amplifying the electrical signal, a bit rate-sensing circuit for generating a sensing signal with a voltage level determined on the basis of the bit rate of the electrical signal, a bit rate-recognition circuit for generating a recognition signal further amplified from the sensing signal, and a clock/data recovery circuit for reproducing a clock signal and data from the amplified electrical signal in accordance with a control signal.

Abstract: The provided forward error correction (FEC) apparatus for a transmission system includes a low pass filter (LPF) passing only a low frequency component of an input signal having a predetermined transmission rate; an AC power meter converting an energy value of an signal output from the LPF into a DC voltage value; a logarithm amplifier converting the exponentially varying DC voltage value from the AC power meter into a linear logarithmically varying DC voltage value; a digital signal processor (DSP) determining the transmission rate of the input signal according to a magnitude of the linear DC voltage value and outputting a control signal according to the transmission rate; a clock generator receiving the control signal and generating a clock signal according to the control signal; and a FEC module receiving the clock signal and performing FEC operation on the received signal. A method for FEC is also provided.

Abstract: Disclosed is a temperature controller and method for maintaining an optical-communication device at a constant temperature regardless of ambient temperature variation.

Abstract: A bit rate control apparatus having a delay unit for delaying an input signal received in an optical receiver in an optoelectrically-converted state; a DC level outputting unit for exclusively OR'ing the input signal with the delayed signal outputted from the delay unit; an A/D converting unit for A/D converting a DC level outputted from the DC level outputting unit; a clock/data reproducing unit for reproducing clocks and data based on a bit rate control signal; and a control unit for calculating a variation in the DC level at every interruption timing, which is previously set, based on the A/D converted signal, and for determining whether the DC level variation occurs under the influence of temperature or due to a variation in bit rate based on a difference between the calculated DC level variation from a predetermined variation limit.

Abstract: A temperature compensation device for an optical communication device or the like is constructed so that an error value, which is the difference between the current temperature and a reference temperature, is subjected to digital processing in a temperature comparison unit. A digital error voltage value is calculated and digital PID control is performed instead of analog PID which requires electric components such as a power op-amp, a resistor (R), and a capacitor (C). According to this construction it is possible to reduce the number of electric parts. It is also possible to accept various types of temperature sensors while using only one PCB regardless of the types of temperature sensors utilized.

Abstract: A temperature compensation device for an optical communication device or the like is constructed so that an error value, which is the difference between the current temperature and a reference temperature, is subjected to digital processing in a temperature comparison unit. A digital error voltage value is calculated and digital PID control is performed instead of analog PID which requires electric components such as a power op-amp, a resistor (R), and a capacitor (C). According to this construction it is possible to reduce the number of electric parts. It is also possible to accept various types of temperature sensors while using only one PCB regardless of the types of temperature sensors utilized.

Abstract: Disclosed is a temperature controller and method for maintaining an optical-communication device at a constant temperature regardless of ambient temperature variation.

Abstract: A receiver in an optical network with a bit rate detection circuit for automatically detecting input signal data bit rates to automatically adjust the frequency of a voltage controlled oscillator in the receiver is disclosed. The receiver has a data rate detection and frequency adjustment circuit which automatically detects the data rate of an input signal and automatically adjusts the frequency of the VCO in the receiver in accordance with the data rate of the input signal. The data rate detection and frequency adjustment circuit detects the data rate of the input signal by converting the input signal into a DC voltage value that varies with respect to the data rate of the input signal.

Abstract: An apparatus and method for forward error correction (FEC) on a variable code length are provided.

Abstract: An automatic gain control device of an optical fiber amplifier that outputs a compensation signal to control a gain value of the optical fiber amplifier is disclosed.

Abstract: A bit rate-independent optical receiver ensures transparency with respect to changes of the transmission format and its associated bit rate in relation to an optical communications system. The optical receiver includes an opto-electric converter for converting an input optical signal into an electric signal, an amplifier circuit for amplifying the electrical signal, a bit rate-sensing circuit for generating a sensing signal with a voltage level determined on the basis of the bit rate of the electrical signal, a bit rate-recognition circuit for generating a recognition signal further amplified from the sensing signal, and a clock/data recovery circuit for reproducing a clock signal and data from the amplified electrical signal in accordance with a control signal.

Abstract: An automatic gain control device of an optical fiber amplifier that outputs a compensation signal to control a gain value of the optical fiber amplifier is disclosed.

Abstract: A bit rate control apparatus and method for an optical receiver capable of avoiding an erroneous determination of the bit rate occurring under the influence of temperature.