Abstract:
The present invention relates to a solar cell that can recycle a substrate, and a manufacturing method thereof. The solar cell includes: i) a plurality of nano-structures distanced from each other and extended in one direction; ii) a first conductive layer covering a first end of at least one of the plurality of nano-structures; iii) a second conductive layer distanced from the first conductive layer and covering a second end of the nano-structure; and iv) a dielectric layer disposed between the first conductive layer and the second conductive layer.
Abstract:
The inventive concept provides optic couplers, optical fiber laser devices, and active optical modules using the same. The optic coupler may include a first optical fiber having a first core and a first cladding surrounding the first core, a second optical fiber having a second core transmitting a signal light to the first optical fiber and a third cladding surrounding the second core, third optical fibers transmitting pump-light to the first optical fiber in a direction parallel to the second optical fiber; and a connector connected between the first optical fiber and the second optical fiber, the connector extending the third optical fibers disposed around the second optical fiber toward the first optical fiber, the connector comprising a third core connected between the first core and the second core and a fifth cladding surrounding the third core.
Abstract:
There are provided an optical fiber coupler configured to improve or optimize optical efficiency and coupling efficiency, a method of manufacturing the optical fiber coupler, and an active optical module. The optical fiber coupler includes a first optical fiber and second optical fibers. The first optical fiber includes a first core and a first cladding surrounding the first core, and the second optical fibers are coupled to the first cladding. The first cladding includes a first coupling facet to which ends of the second optical fibers are coupled.
Abstract:
In a soft decision method for demodulation of a received square QAM (Quadrature Amplitude Modulation) signal, the processing speed is improved, and the manufacturing expense is reduced, by using condition probability vector values, which are soft decision values. A condition judgment operation is employed.
Abstract:
Provided is a gain-clamped (GC) optical amplifier using a fiber Raman amplifier (FRA) having a Raman cavity. The FRA having a Raman cavity comprises a Raman fiber module (RFM) amplifying and outputting an input optical signal and a resonant cavity generating a Raman laser and a gain clamping laser (GC laser), wherein the resonant cavity is formed as a feedback loop between an input terminal and an output terminal of the RFM. Accordingly, a gain of an optical signal propagating along a core of RFM keeps a constant value regardless of input signal intensity by generating the GC laser for gain clamping between a wavelength band of the Raman laser and a gain band of input signals.
Abstract:
Provided is a gain-clamped optical amplifier amplifying light without bandwidth loss of an incident optical signal, and the gain-clamped optical amplifier using a double-clad fiber comprises: an optical fiber including a core doped with a gain material for amplifying an optical signal, a primary clad adjacent to the outside of the core and having a lower refractive index than the core, and a secondary clad adjacent to the outside of the primary clad and having a lower refractive index than the primary clad; a light emitting element emitting a pump light for population inversion of the gain material; and a cavity unit producing laser oscillation by resonating spontaneous emission light emitted from the gain material population-inverted by the pump light.
Abstract:
Provided is an apparatus for manufacturing an optical fiber Bragg grating. The optical fiber Bragg grating manufacturing apparatus includes: an optical fiber; a laser for irradiating a laser beam to the optical fiber to change a refractive index of a core of the optical fiber; an optical system for periodically changing the intensity of the laser beam irradiated to the optical fiber core; a broadband light source for providing broadband light as an incident signal to the optical fiber in order to observe a reflection characteristic of a Bragg grating formed in the optical fiber by the laser beam converted by the optical system; and an optical spectrum analyzer (OSA) for measuring a reflected signal or a transmitted signal of the broadband light incident to the Bragg grating, wherein the optical system realizes a Bragg wavelength (λB) in order to periodically change the refractive index of the optical fiber core, and the broadband light source and the optical spectrum analyzer use λB/N, where λB denotes the Bragg wavelength and N is a natural number which is equal to or more than 2.
Abstract:
The invention relates to a hard decision demodulation of a square type of a quadrature amplitude modulation signal, in particular, to a hard decision demodulation method and apparatus capable of performing fast and accurate demodulation, by demodulating a received signal in bit unit when demodulating it. In a hard decision demodulation method of a square type of quadrature amplitude modulation signal, by determining in bit unit, not in symbol unit a corresponding output value from a quadrature phase component value and an in-phase component value, it is possible to develop a more useful demodulation technique and to give a secondary function by independently processing each bit, according to the demodulation of bit unit. Further, the invention can be constituted of merely a comparison circuit without having arithmetic in demodulation process, and therefore, can enhance flexibility of actual configuration and processing speed.
Abstract:
The present invention relates to a demodulation method using soft decision for QAM (Quadrature Amplitude Modulation). In a soft decision method for demodulation of a received signal of square QAM comprised of the same phase signal component and a orthogonal phase signal component, the demodulation method using soft decision has a characteristic wherein the processing speed is improved, and the manufacturing expense is reduced by gaining a condition probability vector value, which is each soft decision value, corresponding to a beat position of hard decision using a function which includes a condition judgement operation from a orthogonal phase component value of a received signal and the same phase component value.
Abstract:
The present invention relates to a hermetic rotary compressor. More particularly, since the conventional rotary compressor has problems that the effect of a surge recess for reducing noises due to pressure pulsation is insufficient, and it is impossible to obtain the maximum compression efficiency, the present invention is constructed such that noises due to pressure pulsation can be reduced to the maximum and at the same time the compressive driving force required for compressing gaseous refrigerant is decreased to thereby improve the compression efficiency. In a hermetic rotary compressor which comprises a crankshaft which has an eccentric portion formed therein and is rotated by receiving driving force of a motor unit, a rolling piston which is inserted into an eccentric portion of the crankshaft, a cylinder in which a space portion into which the rolling piston is inserted is formed to thereby form a space portion between the inner surface of the cylinder and the outer surface of the rolling piston, upper and lower bearings, each of which is connected to the cylinder to thereby enclosing the space portion and at the same time support the crankshaft, and a vane which is installed to penetrates the inner wall of the cylinder, linearly reciprocate in a radius direction of the cylinder, and linearly contact with the outer surface of the rolling piston, whereby the space portion of the cylinder is partitioned into a suction area and a compression area according to the rotation of the crankshaft, there is a provided a hermetic rotary compressor, wherein a surge recess is formed at 80˜90 degrees in a rotational direction of the crankshaft from the vane, have a volume corresponding to 0.5˜2% of the overall volume of the space portion, and is partially communicated with the cylinder space portion.