Abstract: Disclosed is a method for programming a nonvolatile memory device including one time programmable unit cells. The method for programming a nonvolatile memory device including one time programmable (OTP) unit cells, the method comprising applying a pulse type program voltage having a plurality of cycles. The present invention relates to a method for programming a nonvolatile memory device, which can prevent malfunctions by enhancing a data sensing margin in a read operation through the normal dielectric breakdown of an antifuse during a program operation, and thus improve the reliability in the read operation of an OTP unit cell.

Abstract: Disclosed is a method for programming a nonvolatile memory device including one time programmable unit cells. The method for programming a nonvolatile memory device including one time programmable (OTP) unit cells, the method comprising applying a pulse type program voltage having a plurality of cycles. The present invention relates to a method for programming a nonvolatile memory device, which can prevent malfunctions by enhancing a data sensing margin in a read operation through the normal dielectric breakdown of an antifuse during a program operation, and thus improve the reliability in the read operation of an OTP unit cell.

Abstract: Provided is a dermal scar treatment equipment. The treatment equipment includes a pad, a plurality of pins, and an insulating layer. The pad electrically connects with a high frequency generator. The pins are protrusively coupled to a front of the pad, are inserted into collagen fibers in the dermis through the epidermis, and propagate a high frequency to the collagen fibers. The insulating layer is coated on an end of each of the pins and isolates the pins from the epidermis for no contact.

Abstract: The present invention is directed toward a laser wavelength locking scheme suitable for incorporation into WDM systems having channel spacings of 25 GHz or less. In a preferred embodiment, light output from the laser is supplied to a filtering element, such as an in-fiber Bragg grating or an etalon, and photodetectors are used to sense light transmitted through and either reflected by the filtering element or input to the filtering element. A measured ratio corresponding to a quotient of the photocurrents generated by the photodetectors is calculated and compared to a desired ratio corresponding to a measured temperature of the filtering element when the filtering element transmits the desired wavelength to be locked. Based on the comparison of the desired and measured ratios, a temperature error value is calculated which is used to adjust the laser temperature, as well as the laser wavelength.

Abstract: A system and method is provided for operating a node in an optical Ethernet network system, comprising: generating optical signals of at least one wavelength corresponding to the node; transmitting the optical signals on each of the first and second optical fiber paths; receiving optical signals of the at least one wavelength, either directly or indirectly, from the first and second optical fiber paths; and selectively choosing signals from, either directly or indirectly, either the first or second optical fiber paths depending on the optical signals received from the first or second optical fiber path.

Abstract: The dynamic range of an optical amplifier is extended by the addition of a power control circuit. A switch is interposed between a current source and an optical pump supplying pumping light to the gain medium of the optical amplifier. A modulated signal such as a pulse-width modulated signal is used to actuate the switch and control a relative duration of the “on” and “off” periods of the electrical current supplied to the optical pump. Gain latency in the optical amplifier permits a substantially continuous signal to be output from the optical amplifier in response to the switched electrical current supply to the optical pump. A controller may used a feedback signal from the optical pump or from a power monitoring device to control the modulator and, thereby, the switch. A target pump power level, target gain or target amplified signal power level may also be applied in a feedback control loop that controls the modulator and switch.

Abstract: The invention is a semiconductor optical device and method of fabrication where the device includes an active region with an active layer having a first index of refraction, and a blocking region having a second, lower index of refraction. A semiconductor layer having an index of refraction higher than the blocking region formed over both the active and blocking regions so that the layer is in closer proximity to the active layer in areas not covered by the blocking region so as to decrease the difference between the effective index of refraction in the active region and the effective refractive index of the blocking region. Such devices are particularly useful for pumping optical amplifiers since greater power can be achieved while maintaining single mode emission.

Abstract: The invention is a semiconductor optical device and method of fabrication where the device includes an active region with an active layer having a first index of refraction, and a blocking region having a second, lower index of refraction. A semiconductor layer having an index of refraction higher than the blocking region is formed over both the active and blocking regions so that the semiconductor layer is in closer proximity to the active layer in areas not covered by the blocking region so as to decrease the difference between the effective index of refraction in the active region and the effective refractive index of the blocking region. Such devices are particularly useful for pumping optical amplifiers since greater power can be achieved while maintaining single mode emission.

Abstract: The invention is an optical apparatus and method of fabrication wherein an optical device such as a semiconductor laser includes a grating and a waveguide optically coupled to the grating. At least a portion of the waveguide coupled to the grating has a width which varies along the length of the waveguide in such a manner as to broaden the spectral line width of light output from the device. The width can be varied according to linear, sinusoidal or saw-tooth functions. A broadened line width permits pumping of a Raman amplifier at a high power without inducing any significant Brillouin Scattering.

Abstract: A semiconductor laser having a single transverse mode operation. Optical power higher than that generated by conventional pump lasers is achieved by widening the gain medium without inducing the second transverse mode. This is accomplished by providing a small refractive index difference between active and blocking regions of the laser. The refractive index difference between the laser active region material and the laser blocking region material at the fundamental frequency is less than about 0.029.

Abstract: An exemplary embodiment of the invention is a Raman amplifier for use in an optical communications network. The Raman amplifier includes a plurality of pump lasers and a plurality of wavelength control modules, each associated with one of the pump lasers. Each wavelength control module includes a fiber Bragg grating optically coupled to a respective one of the plurality of pump lasers. The fiber Bragg grating receives a pump laser output from one of the pump lasers and generates a wavelength control module output. A temperature sensor is in thermal contact with the fiber Bragg grating and generates a temperature signal indicative of a temperature of the fiber Bragg grating. A controller is operatively connected to the temperature sensor and generates a control signal in response to the temperature signal. A thermal regulator is in thermal contact with the fiber Bragg grating and adjusts the temperature of the fiber Bragg grating in response to the control signal.

Abstract: A semiconductor laser having a single transverse mode operation. Optical power higher than that generated by conventional pump lasers is achieved by widening the gain medium without inducing the second transverse mode. This is accomplished by providing a small refractive index difference between active and blocking regions of the laser. The refractive index difference between the laser active region material and the laser blocking region material at the fundamental frequency is less than about 0.029.

Abstract: The present invention provides a method for monolithic integration of multiple devices on an optoelectronic substrate. The method, in a preferred embodiment, includes forming an active layer having a given wavelength over a substrate. The method further includes forming an N-type doped layer over a portion of the active layer to form first and second active regions within the active layer, the first active region having the given wavelength and the second active region having an altered wavelength different from the given wavelength. In one exemplary embodiment, the conditions used to form the N-type doped layer, for example, dopant concentration, growth rate and temperature, cause the difference in wavelength between the given wavelength and the altered wavelength.

Abstract: The present invention provides a method for monolithic integration of multiple devices on an optoelectronic substrate. The method, in a preferred embodiment, includes forming an active layer having a given wavelength over a substrate. The method further includes forming an N-type doped layer over a portion of the active layer to form first and second active regions within the active layer, the first active region having the given wavelength and the second active region having an altered wavelength different from the given wavelength. In one exemplary embodiment, the conditions used to form the N-type doped layer, for example, dopant concentration, growth rate and temperature, cause the difference in wavelength between the given wavelength and the altered wavelength.

Abstract: A semiconductor laser having a single transverse mode operation. Optical power higher than that generated by conventional pump lasers is achieved by widening the gain medium without inducing the second transverse mode. This is accomplished by providing a small refractive index difference between active and blocking regions of the laser. The refractive index difference between the laser active region material and the laser blocking region material at the fundamental frequency is less than about 0.029.