Abstract: The present disclosure relates to a tunable laser module including a light gain area unit for outputting an optical signal; an optical distributor for separating the optical signal output from the light gain area unit; two comb reflection units for reflecting a part of optical signals separated by the optical distributor and allow a part of the optical signals to penetrate; two phase units for changing phases of the optical signals penetrating the two comb reflection units; an optical coupler for combining the optical signals of which the phases are changed by the two phase units; and an optical amplifier for amplifying the optical signal combined by the optical coupler, wherein the light gain area unit oscillates a laser by totally reflecting the optical signals reflected by the two comb reflection units.

Abstract: Provided are a reflective semiconductor optical amplifier (R-SOA) and a superluminescent diode (SLD). The R-SOA includes: a substrate; an optical waveguide including a lower clad layer, an active layer independent of the polarization of light, and an upper clad layer sequentially stacked on the substrate, the optical waveguide comprising linear, curved, and tapered waveguide areas; and a current blocking layer formed around the optical waveguide to block a flow of current out of the active layer, wherein the linear and curved waveguide areas have a single buried hetero (BH) structure, and the tapered waveguide area has a dual BH structure.

Abstract: Provided are a high-speed superluminescent diode, a method of manufacturing the same, and a wavelength-tunable external cavity laser including the same. The superluminescent diode includes a substrate having an active region and an optical mode size conversion region, waveguides including an ridge waveguide in the active region and a deep ridge waveguide in the optical mode size conversion region connected to the active waveguide, an electrode disposed on the ridge waveguide; planarizing layers disposed on sides of the ridge waveguide and the deep ridge waveguide on the substrate, and a pad electrically connected to the electrode, the pad being disposed on the planarizing layers outside the active waveguide.

Abstract: Provided is a wavelength-tunable external cavity laser. The wavelength-tunable external cavity laser includes a housing, a planar lightwave circuit (PLC) device disposed within the housing, a pump light source disposed at a side of the PLC device within the housing, and a modulation part disposed at the other side of the PLC device facing the pump light source within the housing.

Abstract: Provided is an external cavity laser light source. The light source includes a substrate, an optical waveguide, and a current blocking layer. The optical waveguide includes a passive waveguide layer, a lower clad layer, an active layer, and an upper clad layer that are sequentially stacked on the substrate and is divided into regions including a linear active waveguide region, a bent active waveguide region, a tapered waveguide region, and a window region. The current blocking layer was formed an outside of the active layer to reduce leakage current. The linear and bent active waveguide regions have a buried heterostructure (BH), and the tapered waveguide region and the window region have a buried ridge stripe (BRS) structure. The passive waveguide layer a width substantially equal to a maximal width of the tapered waveguide region at least in the bent active waveguide region, the tapered waveguide region, and the window region.

Abstract: Provided are a reflective semiconductor optical amplifier (R-SOA) and a superluminescent diode (SLD). The R-SOA includes: a substrate; an optical waveguide including a lower clad layer, an active layer independent of the polarization of light, and an upper clad layer sequentially stacked on the substrate, the optical waveguide comprising linear, curved, and tapered waveguide areas; and a current blocking layer formed around the optical waveguide to block a flow of current out of the active layer, wherein the linear and curved waveguide areas have a single buried hetero (BH) structure, and the tapered waveguide area has a dual BH structure.

Abstract: Provided are a reflective semiconductor optical amplifier (R-SOA) and a superluminescent diode (SLD). The R-SOA includes: a substrate; an optical waveguide including a lower clad layer, an active layer independent of the polarization of light, and an upper clad layer sequentially stacked on the substrate, the optical waveguide comprising linear, curved, and tapered waveguide areas; and a current blocking layer formed around the optical waveguide to block a flow of current out of the active layer, wherein the linear and curved waveguide areas have a single buried hetero (BH) structure, and the tapered waveguide area has a dual BH structure.

Abstract: A method and apparatus for modulating a particular light source used for laser display are provided. The apparatus includes a digital modulator digitally modulating light output from a semiconductor laser to a frequency higher than a repetition frequency required for laser image display; and a pixel brightness adjustor inserting at least one high-speed pulse into a period of the modulated output light, which is required for a single pixel, and adjusting a brightness of the pixel by adjusting the number of the inserted high-speed pulses.

Abstract: Provided is an external cavity laser light source. The light source includes a substrate, an optical waveguide, and a current blocking layer. The optical waveguide includes a passive waveguide layer, a lower clad layer, an active layer, and an upper clad layer that are sequentially stacked on the substrate and is divided into regions including a linear active waveguide region, a bent active waveguide region, a tapered waveguide region, and a window region. The current blocking layer was formed an outside of the active layer to reduce leakage current. The linear and bent active waveguide regions have a buried heterostructure (BH), and the tapered waveguide region and the window region have a buried ridge stripe (BRS) structure. The passive waveguide layer a width substantially equal to a maximal width of the tapered waveguide region at least in the bent active waveguide region, the tapered waveguide region, and the window region.

Abstract: Provided is a super luminescent diode having low power consumption due to low threshold current and a high output power in low-current operation, which is suitable for an external cavity laser. The super luminescent diode for use in the external cavity laser is divided into a super luminescent diode (SLD) region and a semiconductor optical amplifier (SOA) region to provide a light source having a low threshold current and a nearly double output power of a conventional SLD.

Abstract: Provided is a tunable external cavity laser. The tunable external cavity laser includes that a bragg grating hermetically packaged in a TO can, a superluminescent diode (SLD) using an optical source signal and an optical fiber. A lasing wavelength is decided when the optical source signal emitted from the SLD is reflected by the bragg grating and the lasing wavelength is output to the optical fiber through the SLD.

Abstract: A channel switching function is added to a wavelength division multiplexing passive optical network (WDM-PON) system, which is an access optical network system, and the potential transmission rate is increased by combining wide wavelength tunable lasers and a time division multiplexing (TDM) data structure and properly using the necessary optical components. In addition, when the wavelength of a light source or an arrayed waveguide grating (AWG) changes, the wavelength is traced and the magnitude of a transmitted signal is maximized without an additional detour line using a loop-back network structure. Furthermore, fewer thermo-electric controllers (TECs) are required for stabilizing the temperature of an optical line terminal (OLT) using wavelength tunable lasers, each laser electrically changing its wavelength.

Abstract: Provided is a buried ridge waveguide laser diode that has improved temperature characteristics and can reduce optical loss by a leakage current. The buried ridge waveguide laser diode includes: a ridge region that extends vertically with a constant width and is composed of a selective etching layer and a first compound layer formed of a first conductive type material on a portion of the clad layer; and a p-n-p current blocking layer that has a thickness identical to the depth of the ridge region on the clad layer outside the ridge region and includes a second compound layer formed of a second conductive type material opposite to the first conductive type material. At this time, the current blocking layer includes the first compound layer extending on the second compound layer.

Abstract: Provided is a super luminescent diode having low power consumption due to low threshold current and a high output power in low-current operation, which is suitable for an external cavity laser. The super luminescent diode for use in the external cavity laser is divided into a super luminescent diode (SLD) region and a semiconductor optical amplifier (SOA) region to provide a light source having a low threshold current and a nearly double output power of a conventional SLD.

Abstract: Provided are a reflective semiconductor optical amplifier (R-SOA) and a superluminescent diode (SLD). The R-SOA includes: a substrate; an optical waveguide including a lower clad layer, an active layer independent of the polarization of light, and an upper clad layer sequentially stacked on the substrate, the optical waveguide comprising linear, curved, and tapered waveguide areas; and a current blocking layer formed around the optical waveguide to block a flow of current out of the active layer, wherein the linear and curved waveguide areas have a single buried hetero (BH) structure, and the tapered waveguide area has a dual BH structure.

Abstract: Provided is a method of fabricating a semiconductor optical device for use in a subscriber or a wavelength division multiplexing (WDM) optical communication system, in which a laser diode (LD) and a semiconductor optical amplifier (SOA) are integrated in a single active layer. The laser diode (LD) and the semiconductor optical amplifier (SOA) are optically connected to each other, and electrically insulated from each other by ion injection, whereby light generated from the LD is amplified by the SOA to provide low oscillation start current and high intensity of output light when current is individually injected through each electrode.

Abstract: A method and apparatus for modulating a particular light source used for laser display are provided. The apparatus includes a digital modulator digitally modulating light output from a semiconductor laser to a frequency higher than a repetition frequency required for laser image display; and a pixel brightness adjustor inserting at least one high-speed pulse into a period of the modulated output light, which is required for a single pixel, and adjusting a brightness of the pixel by adjusting the number of the inserted high-speed pulses.

Abstract: Provided is a buried ridge waveguide laser diode that has improved temperature characteristics and can reduce optical loss by a leakage current. The buried ridge waveguide laser diode includes: a ridge region that extends vertically with a constant width and is composed of a selective etching layer and a first compound layer formed of a first conductive type material on a portion of the clad layer; and a p-n-p current blocking layer that has a thickness identical to the depth of the ridge region on the clad layer outside the ridge region and includes a second compound layer formed of a second conductive type material opposite to the first conductive type material. At this time, the current blocking layer includes the first compound layer extending on the second compound layer.

Abstract: A tunable semiconductor laser including a Fabry-Perot filter and an electrode array is disclosed. The propagation direction of the light beam in the cavity can be consecutively shifted applying electric field or current to the electrode and tuning can consecutively performed over the wide wavelength band by the consecutive shift of the angle of the intra cavity laser beam.

Abstract: The present invention relates to a semiconductor laser, having a construction capable of tuning a wavelength, in which a sampled grating distributed feedback SG-DFB structure portion and a sampled grating distributed Bragg reflector SG-DBR structure portion are integrated. In the present invention, the refraction index are varied in accordance with a current applied to the phase control area in the SG-DFB structure portion and the SG-DBR structure portion, whereby it is possible to continuously or discontinuously tune the wavelength. Therefore, in such a wavelength tunable semiconductor laser, its construction is relatively simple, and it is relatively useful to the manufacturing and mass-producing the semiconductor laser. In addition, such a wavelength tunable semiconductor laser has an excellent output optical efficiency while making it possible to tune the wavelength of the wide band.