Abstract: A light source includes a semiconductor laser diode and a narrow spectral and spatial bandwidth reflector in optical communication with respect to the semiconductor diode laser and aligned with the output beam of the diode laser, such that a portion of the light in the output beam is reflected back into the laser.

Abstract: A light source includes a semiconductor laser diode and a narrow spectral and spatial bandwidth reflector in optical communication with respect to the semiconductor diode laser and aligned with the output beam of the diode laser, such that a portion of the light in the output beam is reflected back into the laser.

Abstract: A semiconductor diode laser has a characteristic output with a single mode vertical far-field divergence. The semiconductor diode laser includes a waveguide with a first refractive index and a quantum well embedded in the center of the waveguide. On one side of the waveguide sits a p-type cladding layer with a second refractive index smaller than the first refractive index. On the other side of the waveguide sits an n-type cladding layer with a third refractive index smaller than the first refractive index and larger than the second refractive index.

Abstract: A diode laser comprises a laser cavity defining a linear optical-path axis, and a current-pumped stripe region, said current-pumped stripe region being disposed within said laser cavity. The laser cavity includes an output surface perpendicular to the optical axis; and a reflection surface including a distributed Bragg reflector (DBR) grating and being disposed at a non-perpendicular angle to the optical-path axis.

Abstract: An apparatus includes a single-mode master-oscillator section and a power amplifier section. The single-mode master-oscillator section includes a waveguide defined by a first end and a second end, the first end including a first distributed Bragg reflector mirror, and the second end including a second distributed Bragg reflector mirror. The single-mode-master-oscillator section also has a first longitudinal axis. The power amplifier section is a broad-contact amplifier coupled to the single-mode-master-oscillator section by a coupling grating that is contained in the waveguide of the single-mode-master-oscillator section. The broad contact amplifier section includes a reflection side, an output side and a second longitudinal axis, the second longitudinal axis being at an angle approximately (90°−&bgr;) to said first longitudinal axis, &bgr; being in a range between 0° and approximately 20°.

Abstract: An apparatus comprises an active region, a phosphor layer and a substrate. The active region is configured to emit light having a first band of wavelengths selected from a first group of wavelengths. The phosphor layer has a first refractive index. The phosphor layer includes a plurality of wavelength-converting phosphors. The phosphor layer is configured to convert the first band of wavelengths of light emitted from the active region to a second band of wavelengths. A center wavelength of the second band of wavelengths is greater than a center wavelength of the first band of wavelengths. The substrate is disposed between and in contact with the active region and the phosphor layer. The substrate has a second refractive index. The first refractive index substantially equals the second refractive index.

Abstract: A wavelength division multiplex optical crossconnect system and add/drop multiplexer including a dense wavelength division multiplexed (DWDM) source which preferably includes a multiwavelength mode-locked (MWML) external cavity laser as a fundamental sub-circuit for optically crossconnecting several multi-wavelength data channels onto similar data channels having an interchanged set of optical wavelengths. The optical crossconnect architecture allows the rearrangement of multiple logical channels in a timely manner to support protection switching, traffic grooming, and other telecommunications network functions. The crossconnect architecture further supports multiple physical fibers into and out of the crossconnect, where each fiber carries multiple logical channels on multiple wavelengths of light which are assigned particular wavelength carriers, crossconnected onto any other physical fiber, and assigned another wavelength carrier.

Abstract: An apparatus, comprises an active region, a phosphor layer and a reflective layer. The active region is configured to emit light having a first band of wavelengths from a first group of wavelengths. The phosphor layer is disposed between and in contact with the active region and an exterior medium. The phosphor layer is configured to convert the first band of wavelengths of light emitted from the active region to a second band of wavelengths. A center wavelength of the second band of wavelengths is greater than a center wavelength of the first band of wavelengths. The reflective layer is optically coupled to the active region. The active region is disposed between the reflective layer and the phosphor layer. The reflective layer is configured to reflect at least the first band of wavelengths and the second band of wavelengths.

Abstract: A semiconductor laser device with separated, highly-strained quantum wells employs highly-strained ternary and quasi-ternary compounds as material for each quantum well. A first device structure includes a quantum well composition range extended from strained ternary compounds employed in conventional quantum well laser devices. A second device structure, employing a similar structure to that of the first device, employs new quasi-ternary compounds with compositions outside of the miscibility gap of corresponding quaternary compounds for quantum wells in GaSb— or InAs-based laser devices which extend performance of mid-infrared laser devices operating in the 2.2-4.0 &mgr;m range. The semiconductor diode laser may be formed so as to operate having a multi-mode or single-mode radiation.

Abstract: A semiconductor diode laser with thermal sensor control comprises a heat sink, a diode-laser structure, and a thermal sensor thermally coupled to said diode-laser structure in a place where the temperature gradient across the semiconductor diode laser is close to zero.

Abstract: A thermophotovoltaic cell and diode photodetector having improved open circuit voltage and high internal efficiency includes a semiconductor body having regions of n-type conductivity and p-type conductivity adjacent each other to form a p-n junction therebetween. The p-type region is of a material having a band gap which will absorb black-body radiation and the n-type region is of a material having a wider band gap than that of the p-type region. This forms a heterojunction between the two regions. The region of n-type region has a doping level which is an order of magnitude less than the doping level in the p-type region. This structure forms a cell having a space charge region in the n-type region.

Abstract: A multi-wavelength mode-locked dense wavelength division multiplexed (MWML-DWDM) optical transmission method and system including a MWML-DWDM optical transmitter having a multiwavelength mode-locked (MWML) laser which generates a wavelength-ordered repetitive periodic (WORP) sequence of discrete optical pulses for modulation with data carried by at least one electronic carrier. Signals from multiple telecommunications transmission interfaces are multiplexed together by a high speed electronic time domain multiplexer to form a single multiplexed high speed digital transmission stream that is encoded onto the optical pulse stream output by the MWML-DWDM optical transmitter by an optical modulator so as to provide multiple channels of information carried on a DWDM data stream over an optical fiber to a receiver where the data is received and decoded.

Abstract: A semiconductor laser diode having increased efficiency and therefore increased power output. The laser diode includes a body of a semiconductor material having therein a waveguide region which is not intentionally doped so as to have a doping level of no greater than about 5.times.10.sup.16 /cm.sup.3. Within the waveguide region is means, such as at least one quantum well region, for generating an optical mode of photons. Clad regions of opposite conductivity type are on opposite sides of the waveguide region. The thickness of the waveguide region, a thickness of at least 500 nanometers, and the composition of the waveguide and the clad regions are such so as to provide confinement of the optical mode in the waveguide region to the extent that the optical mode generating does not overlap into the clad regions from the waveguide region more than about 5%.

Abstract: A semiconductor laser diode having increased efficiency and therefore increased power output. The laser diode includes a body of a semiconductor material having therein a waveguide region which is not intentionally doped so as to have a doping level of no greater than about 5×1016/cm3. Within the waveguide region is means, such as at least one quantum well region, for generating an optical mode of photons. Clad regions of opposite conductivity type are on opposite sides of the waveguide region. The thickness of the waveguide region, a thickness of at least 500 nanometers, and the composition of the waveguide and the clad regions are such so as to provide confinement of the optical mode in the waveguide region to the extent that the optical mode generating does not overlap into the clad regions from the waveguide region more than about 5%.