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:
A method is provided for reading data in a nonvolatile memory device. The method includes performing a first read operation on multiple multi-level memory cells (MLCs), performing a first sensing operation on at least one flag cell corresponding to the MLCs, selectively performing a second read operation on the MLCs based on a result of the first sensing operation, and performing a second sensing operation on the at least one flag cell when the second read operation is performed. Read data is output based on results of the first read operation and the first sensing operation when the second read operation is not performed, and the read data is output based on result of the first read operation, the first sensing operation, the second read operation and the second sensing operation when the second read operation is performed. The read data corresponds to programmed data in the MLCs.
Abstract:
A flash memory device controls a common source line voltage and performs a program verify method. A plurality of memory cells is connected between a bit line and the common source line. A data input/output circuit is connected to the bit line and is configured to store data to be programmed in a selected memory cell of the plurality of memory cells. The data input/output circuit maintains data to be programmed within the data input/output circuit during a program verify operation, and decreases noise in the common source line by selectively precharging the bit line based on the data to be programmed.
Abstract:
A non-volatile memory device includes a feedback circuit and a precharge switching transistor. The feedback circuit generates a feedback signal based on a voltage level of a bitline during a precharge operation. The precharge switching transistor, in response to the feedback signal, controls a precharge current for precharging the bitline. The speed of the precharge operation may be increased and/or mismatch of the bias signals in precharging a plurality of bitlines may be reduced.
Abstract:
Provided is a resonator of a hybrid laser diode. The resonator includes: a substrate including a semiconductor layer where a hybrid waveguide, a multi-mode waveguide, and a single mode waveguide are connected in series; a compound semiconductor waveguide, provided on the hybrid waveguide of the semiconductor layer, having a tapered coupling structure at one end of the compound semiconductor waveguide, the tapered coupling structure overlapping the multi-mode waveguide partially; and a reflection part provided on one end of the single mode waveguide. The multi-mode waveguide has a narrower width than the hybrid waveguide and the single mode waveguide has a narrower width than the multi-mode waveguide.
Abstract:
Provided is a mask pattern for selective area growth of a semiconductor layer and a selective area growth method for a semiconductor layer for independently controlling a growth rate and a strain of the semiconductor layer. The selective area growth method includes: forming a plurality of pairs of first mask patterns, the first mask patterns in each pair including a first open area therebetween, the first open area having a width that is wider than a distance causing overgrowth of the semiconductor layer, the pairs of the first mask patterns repeatedly arranged with a period P therebetween; wherein controlling a growth rate and a strain of the semiconductor layer formed on the first open area by adjusting the period P.
Abstract:
A program verification method is for a nonvolatile memory device which programs a plurality of memory cells. The program verification method includes applying a plurality of verification voltages, and determining whether programming of memory cells, having different target threshold voltage distributions, from among the plurality of memory cells is completed based on one of the plurality of verification voltages.
Abstract:
Provided are an optical coupler, which can improve miniaturization and integration, and an active optical module comprising the same. The optical coupler comprises a hollow optical block having a through hole formed to pass an optical fiber therethrough. The hollow optical block comprises at least one incidence plane, at least one internal reflection plane, and at least one tapering region. The incidence plane is disposed at the bottom of the hollow optical block, which is parallel to the through hole, to incident-transmit light. The internal reflection plane is disposed at the top of the hollow optical block, which is opposite to the incidence plane, to reflect the light, which is received from the incidence plane, into the hollow optical block. The tapering region is configured to concentrate the light on the optical fiber in the through hole. The tapering region is formed such that the outer diameter of the hollow optical block decreases away from the internal reflection plane and the incidence plane.
Abstract:
A system for accessing a node of a private network includes an assigning portion for assigning external port values to respective network nodes based on information collected from the network nodes of the private network, and storing the assigned external port values; an exchanging portion for exchanging the external port values of the respective network nodes of private networks; and an address converting portion for converting the external port values into corresponding private IP addresses and internal port values when a network node of one private network accesses another network node of another private network by using the external port values of another network node of another private network. Accordingly, a network node of a private network without a global IP address becomes accessible.
Abstract:
A semiconductor optical device with a differential grating formed by a holography method and a method for manufacturing the same are provided. The provided semiconductor optical device includes an n-type InP substrate, a stack structure on the InP substrate having a waveguide and active layers, a first grating formed under the stack structure and on the InP substrate, and a second grating formed on the stack structure. The provided method for manufacturing the semiconductor optical device forms a first grating on the n-type InP substrate and under the active layer, and forms a second grating on the active layer. The first and second gratings are formed by the holography method.