Abstract: Disclosed are a Mach-Zehnder interferometric optical modulator and a method for manufacturing the same. The modulator includes first and second lower clad layers, a core layer, an upper clad layer, a waveguide, and electrodes. The waveguide may include an input waveguide, a waveguide divider, branch waveguides, and a waveguide combiner. Each of the branch waveguides includes first and second connection regions connected to the waveguide combiner and the waveguide divider, respectively, and a phase shift region having a cross-section of a reverse mesa structure that has an upper width that is the same as widths of the first and second connection regions and a lower width that is smaller than the widths of the first and second connection regions.

Abstract: Disclosed are a heterogeneously integrated optical modulator and a manufacturing method thereof. The modulator includes a substrate having a trench, an input waveguide disposed at one side of the trench, an output waveguide disposed at the other side of the trench, a first Mach-Zehnder interferometer including first branch waveguides disposed between the input waveguide and the output waveguide and a heater disposed on one of the first branch waveguides, and second Mach-Zehnder interferometers connected to each of the first branch waveguides.

Abstract: Disclosed is an optical transmitter module including a directly modulated laser transmitter based on a directly modulated laser (DML) and an arrayed waveguide grating (AWG) chip that is vertically polished. The directly modulated laser transmitter includes a directly modulated laser chip array including one or more directly modulated laser chips, an impedance matching circuit that allows each of the one or more directly modulated laser chips to operate at a critical speed of 100 Gbps per channel or higher, and a radio frequency-flexible printed circuit board (RF-FPCB) that transmits a radio frequency (RF) modulating signal to the directly modulated laser chip array. The arrayed waveguide grating chip includes an optical waveguides that transfer multi-channel optical signals and a wavelength multiplexer that multiplexes the multi-channel optical signals. The directly modulated laser transmitter and the arrayed waveguide grating chip are spaced apart from each other and are optically coupled in chip-to-chip.

Abstract: Disclosed is an optical transmitter module including a directly modulated laser transmitter based on a directly modulated laser (DML) and an arrayed waveguide grating (AWG) chip that is vertically polished. The directly modulated laser transmitter includes a directly modulated laser chip array including one or more directly modulated laser chips, an impedance matching circuit that allows each of the one or more directly modulated laser chips to operate at a critical speed of 100 Gbps per channel or higher, and a radio frequency-flexible printed circuit board (RF-FPCB) that transmits a radio frequency (RF) modulating signal to the directly modulated laser chip array. The arrayed waveguide grating chip includes an optical waveguides that transfer multi-channel optical signals and a wavelength multiplexer that multiplexes the multi-channel optical signals. The directly modulated laser transmitter and the arrayed waveguide grating chip are spaced apart from each other and are optically coupled in chip-to-chip.

Abstract: Provided are a coherent optical receiver and a fabrication method thereof, the coherent optical receiver including a substrate, signal and local input waveguides extending in a first direction parallel to a top surface of the substrate and configured to receive an optical signal, a first optical circuit element including a first optical waveguide connected to the signal input waveguide and a trench provided in one side of the first optical waveguide in parallel to the first direction, a second optical circuit element including a second optical waveguide connected to the first optical waveguide, a slit crossing the second optical waveguide, and a wavelength plate inserted to the slit, and third optical circuit elements connected to the second optical circuit element, wherein the first to third optical circuit elements are monolithically integrated in the substrate.

Abstract: Provided is an optical module including an optical waveguide device through which multiple channel lightwaves are input and output, an optical transmission/reception unit disposed on one side of the optical waveguide device, an electronic IC disposed on one side of the optical transmission/reception unit and configured to drive the optical transmission/reception unit, a flexible printed circuit board (PCB) disposed on the optical transmission/reception unit and the electronic IC, a first solder ball between the optical transmission/reception unit and the flexible PCB and a second solder ball between the electronic IC and the flexible PCB.

Abstract: Provided are a coherent optical receiver and a fabrication method thereof, the coherent optical receiver including a substrate, signal and local input waveguides extending in a first direction parallel to a top surface of the substrate and configured to receive an optical signal, a first optical circuit element including a first optical waveguide connected to the signal input waveguide and a trench provided in one side of the first optical waveguide in parallel to the first direction, a second optical circuit element including a second optical waveguide connected to the first optical waveguide, a slit crossing the second optical waveguide, and a wavelength plate inserted to the slit, and third optical circuit elements connected to the second optical circuit element, wherein the first to third optical circuit elements are monolithically integrated in the substrate.

Abstract: Provided is an optical circuit element, and more particularly, is an optical circuit element that splits one optical signal into two polarization signals, or couples two polarization signals into one optical signal. The optical circuit element includes a plurality of input couplers to which an optical signal is input, a plurality of output couplers from which an optical signal is output, a first path and a second path configured to connect the input couplers and the second couplers to each other, and at least one wave plate.

Abstract: Provided is an optical module including an optical waveguide device through which multiple channel lightwaves are input and output, an optical transmission/reception unit disposed on one side of the optical waveguide device, an electronic IC disposed on one side of the optical transmission/reception unit and configured to drive the optical transmission/reception unit, a flexible printed circuit board (PCB) disposed on the optical transmission/reception unit and the electronic IC, a first solder ball between the optical transmission/reception unit and the flexible PCB and a second solder ball between the electronic IC and the flexible PCB.

Abstract: Provided is an optical circuit element, and more particularly, is an optical circuit element that splits one optical signal into two polarization signals, or couples two polarization signals into one optical signal. The optical circuit element includes a plurality of input couplers to which an optical signal is input, a plurality of output couplers from which an optical signal is output, a first path and a second path configured to connect the input couplers and the second couplers to each other, and at least one wave plate.

Abstract: Provided herein are a multi-channel receiver optical sub-assembly and a manufacturing method thereof. The multi-channel receiver optical sub-assembly includes a PLC chip having a first side into which an optical signal is received and a second side from which the received signal is outputted, with an inclined surface formed on the second side of the PLC chip at a preset angle, a PD carrier bonded onto the PLC chip and made of a glass material, and an SI-PD bonded onto the PD carrier, a lens being integrated therein. The PLC chip, the PD carrier, and the SI-PD are passively aligned by at least one alignment mark and then are bonded.

Abstract: Provided is an optical transmitter module. The optical transmitter module includes a substrate, a ground layer disposed on the substrate, an electro-absorption modulated laser (EML) chip disposed on the ground layer to generate an modulated optical signal, a ground structure disposed on the EML chip and electrically connected to the ground layer, a matching resistor disposed on the ground structure, and a first bonding wire disposed between the EML chip and the matching resistor to electrically connect the EML chip to the matching resistor.

Abstract: Provided is an optical transmitter module. The optical transmitter module includes a substrate, a ground layer disposed on the substrate, an electro-absorption modulated laser (EML) chip disposed on the ground layer to generate an modulated optical signal, a ground structure disposed on the EML chip and electrically connected to the ground layer, a matching resistor disposed on the ground structure, and a first bonding wire disposed between the EML chip and the matching resistor to electrically connect the EML chip to the matching resistor.

Abstract: Provided herein are a multi-channel receiver optical sub-assembly and a manufacturing method thereof. The multi-channel receiver optical sub-assembly includes a PLC chip having a first side into which an optical signal is received and a second side from which the received signal is outputted, with an inclined surface formed on the second side of the PLC chip at a preset angle, a PD carrier bonded onto the PLC chip and made of a glass material, and an SI-PD bonded onto the PD carrier, a lens being integrated therein. The PLC chip, the PD carrier, and the SI-PD are passively aligned by at least one alignment mark and then are bonded.

Abstract: Provided herein is a radio frequency probe apparatus including a RF waveguide including a ground electrode and a signal electrode, a register connected to the signal electrode, a RF connector including an outer conductor connected to the ground electrode, an inner conductor connected to the signal electrode, and a dielectric body filling a portion between the outer conductor and the inner conductor, and a single tip probe connected to the signal electrode of the RF waveguide, or the register.

Abstract: Provided herein are a multi-channel receiver optical sub-assembly and a manufacturing method thereof. The multi-channel receiver optical sub-assembly includes a PLC chip having a first side into which an optical signal is received and a second side from which the received signal is outputted, with an inclined surface formed on the second side of the PLC chip at a preset angle, a PD carrier bonded onto the PLC chip and made of a glass material, and an SI-PD bonded onto the PD carrier, a lens being integrated therein. The PLC chip, the PD carrier, and the SI-PD are passively aligned by at least one alignment mark and then are bonded.

Abstract: There is provided a receiver optical module including a photodetector having a plurality of channels, a capacitor disposing block formed on an upper portion of the photodetector, a plurality of capacitors formed on the capacitor disposing block, and an electrical wiring configured to connect the plurality of capacitors to electrodes of a plurality of channels of the photodetector, wherein the plurality of capacitors are formed on the capacitor disposing block such that distance between the capacitors and the electrodes of the corresponding channels are the same. Distortion and loss of signal characteristics of high frequency can be reduced and quality of a signal can be enhanced.

Abstract: Provided herein is a semiconductor optical device, including a waveguide including lattices buried therein and having a buried hetero (BH) structure formed in an optical oscillation region in which single mode light is oscillated, a waveguide having a deep ridge structure formed in an optical modulation region, and a passive waveguide formed in a mode transition region interposed between the optical oscillation region and the optical modulation region, formed as a connecting structure of the waveguide having the BH structure extending from the optical oscillation region and the waveguide having the deep ridge structure extending from the optical modulation region, and inducing evanescent optical coupling, wherein a width of the waveguide having the BH structure in the mode transition region is smaller than a width of the waveguide having the deep ridge structure in the optical modulation region.

Abstract: Provided herein is a semiconductor optical device, including a waveguide including lattices buried therein and having a buried hetero (BH) structure formed in an optical oscillation region in which single mode light is oscillated, a waveguide having a deep ridge structure formed in an optical modulation region, and a passive waveguide formed in a mode transition region interposed between the optical oscillation region and the optical modulation region, formed as a connecting structure of the waveguide having the BH structure extending from the optical oscillation region and the waveguide having the deep ridge structure extending from the optical modulation region, and inducing evanescent optical coupling, wherein a width of the waveguide having the BH structure in the mode transition region is smaller than a width of the waveguide having the deep ridge structure in the optical modulation region.

Abstract: Provided herein are a multi-channel receiver optical sub-assembly and a manufacturing method thereof. The multi-channel receiver optical sub-assembly includes a PLC chip having a first side into which an optical signal is received and a second side from which the received signal is outputted, with an inclined surface formed on the second side of the PLC chip at a preset angle, a PD carrier bonded onto the PLC chip and made of a glass material, and an SI-PD bonded onto the PD carrier, a lens being integrated therein. The PLC chip, the PD carrier, and the SI-PD are passively aligned by at least one alignment mark and then are bonded.