Abstract: A p-type InP buffer layer containing Zn in a low concentration and an undoped InP buffer layer having a carrier concentration of 3×1017 cm?3 or less are stacked on a p-type InP substrate containing Zn. On the undoped InP buffer layer, a Mg-doped p-type InP cladding layer, an InGaAsP optical confinement layer, an InGaAsP MQW active layer, an n-type InGaAsP optical confinement layer, and an n-type InP cladding layer are successively stacked. The diffusion of Zn from the p-type InP substrate into the InGaAsP MQW active layer is suppressed. Moreover, a steep doping profile can be formed in the vicinity of the active layer so that deterioration of device characteristics is suppressed.

Abstract: Reverse bias leakage testing may be used to determine the health of a vertical cavity surface emitting laser (VCSEL). When VCSELs are integrated on a die with other electronic devices such testing may damage the other electronic devices or be prohibited by circuits on the die designed to protect the electronics from being reverse biased. Accordingly, reverse bias testing may be facilitated by providing a second ground pad, separate from the die ground pad, specific to the VCSEL.

Abstract: A frequency modulated (FM) vertical cavity surface emitting laser (VCSEL). The frequency modulated VCSEL includes a mirror region that has an active region. The frequency modulated VCSEL also includes a phase adjustment region for use in altering the characteristics of the VCSEL. For example, by changing the index of refraction in the phase adjustment region, the wavelength of the VCSEL can be changed, resulting in frequency modulation.

Abstract: The present invention provides a semiconductor laser element, a method of fabrication thereof, and a multi-wavelength monolithic semiconductor laser device that achieve self-sustained pulsation up to a high output level and achieve self-sustained pulsation over a wide output range.

Abstract: In a semiconductor laser element: a lower cladding layer of a first conductivity type, a quantum-well active layer, an upper cladding layer of a second conductivity type, a contact layer of the second conductivity type, and a first electrode of the second conductivity type are formed in this order above a surface of a semiconductor substrate of the first conductivity type, and a second electrode of the first conductivity type is formed below the lower cladding layer. An optical guide layer is arranged between the quantum-well active layer and one or each of the lower cladding layer and the upper cladding layer. The whole or a portion of the optical guide layer contains a dopant so as to realize a carrier concentration of 3.0×1017 cm?3 or higher.

Abstract: A detector is disposed on the passive side of a laser to detect photon leakage through the passive side mirror and measure as current created in the detector via a Schottky contact.

Abstract: The object of the present invention is to provide an optical module for the WDM communication system, in which the oscillation wavelength is on the grid of the WDM regulation, moreover the optical output power and the oscillation wavelength can be controlled independently. The present module comprises a semiconductor light-emitting device, a wedge shaped etalon device and two light-receiving devices. The etalon device contains a first portion, on which the anti-reflection films are coated, and a second portion. One of the receiving devices detects light transmitted through the first portion of the etalon device, while the other device detects light through the second portion. Signal from the former device controls the output power of the light-emitting device, while the signal from the latter receiving device controls the oscillation wavelength of the laser.

Abstract: A laser apparatus is disclosed combining polarized light beams from two optical emitters into a combined beam of light with controllable degree of polarization (DoP). The laser apparatus includes a polarization combiner for combining the polarized beams into the combined beam, an optical tap for separating out a portion of the combined beam, and a photodetector electrically coupled to a laser controller for providing a feedback signal. The controller distinctively modulates the polarized radiation of each of the emitters, detects modulation signals in the photodetector output and adjusts an output power ratio of the optical emitters for maintaining the DoP of the combined beam at a pre-determined level. The invention can be used for minimizing the DoP of pump radiation in Raman and EDFA pump laser modules combining multiple pump laser diodes.

Abstract: A plurality of subresonators (12, 14), having different design configurations, share a common resonator section (18) such that the lasing action can be substantially synchronized to provide coherent laser pulses that merge the different respective pulse energy profile and/or pulse width characteristics imparted by the configurations of the subresonators (12, 14). The subresonators (12, 14) may share a laser medium (42) in the common section, or each distinct subresonator section (28, 36) may have its own laser medium (42). Exemplary long and short subresonators (12, 14) generate specially tailored laser pulses having a short rise time and a long pulse width at one wavelength or two different wavelengths that may be beneficial for a variety of laser and micromachining applications including memory link processing.

Abstract: An optoelectronic device having a semiconductor laser diode and a grating structure for stabilizing the optical wavelength of optical radiation generated by the laser diode.

Abstract: A Ho:YAG crystal laser is disclosed which is doped with less than 2% holmium to reduce the lasing threshold and up-conversion, thereby increasing the operating efficiency of the laser. The laser does not need sensitizer ions so energy mismatches introduced by the sensitizer ions ale eliminated to the thereby increase the efficiency of the laser while minimizing detrimental thermal loading in the laser caused by up-conversion loss processes. The Ho:YAG crystal laser is directly pumped by a Thulium fiber laser at 1.9 ?m at the holmium 5I7 to 5I8 transition to produce an output at 2.1 ?m yielding a very low quantum defect. The laser is embodied as a thulium fiber laser pumped oscillator or an amplifier.

Abstract: Adjustment of a tunable external-cavity laser is simplified by incorporating a mount that includes a base, a main body, a reflecting surface, a diffracting surface and a hinge coupling the main body to the base. The laser additionally includes a light source, a converging lens located to receive light from the light source, a tuning mirror and a pivoting arm on which the tuning mirror is mounted. The main body is bounded in part by two plane, external surfaces orthogonal to a common reference plane and angularly separated from one another by an angle. The reflecting surface has a spatial orientation defined by one of the external surfaces and is arranged to receive light from the lens. The diffracting surface has a spatial orientation defined by the other of the external surfaces, and diffracts light received from the reflecting surface towards the tuning mirror. The hinge is located opposite the angle and parallel to the reference plane.

Abstract: An infrared laser has a seed laser with an optical seed output. A pump amplifier receives the optical seed output and has an amplified output. A molecular gas laser receives the amplified output and has an infrared optical output.

Abstract: A fundamental laser beam is wavelength converted through nonlinear optical crystals by traveling in one direction, sequentially through two nonlinear optical crystals arranged in series. A wavelength-converted laser beam is generated and includes wavelength-converted laser beams having polarized directions differing from each other by angles in a range from 45° to 90°. The two nonlinear optical crystals have crystal orientation axes differing by 45° to 90° when viewed along the optical axis of the laser beam.

Abstract: Optically-pumped group IIB atomic vapor lasers emitting at discrete wavelengths shorter than 230 nm are disclosed. This laser device utilizes an active medium comprising a mixture of a group IIB atomic vapor and one or more buffer gases placed within a doubly-resonant optical cavity that enables the realization of a population inversion between the first 1P1 level and the 1S0 ground level of the group IIB atoms. The laser may operate in a pure continuous-wave mode, or in a high-repetition pulsed mode, at DUV wavelengths of ˜185 nm (mercury), ˜229 nm (cadmium) and ˜214 nm (zinc).

Abstract: An all-fiber device platform for producing high-power ROGB or RGB laser output comprises an optical fiber including multiple waveguide gain regions embedded within a common inner cladding and within an outer cladding, an optical cavity defined by dielectric reflectors and/or FBG mirrors, and a pump source for exciting one or more active ionic species by one or multiple pump wavelengths from one or both ends of the optical fiber through upconversion process. An apparatus for producing sequential or simultaneous multiple wavelength laser operation provides for applications of color projection displays and biomedical or other instrumentation.

Abstract: The semiconductor laser unit includes: a metal plate having a center portion wider than the remaining portions; a flexible substrate having a first opening; a substrate mounted on the center portion; a semiconductor laser placed on the substrate; a frame having a second opening and fixing the flexible substrate in the state of being bent along from the top surface to both side faces of the metal plate; and an optical element covering the second opening. The flexible substrate is fixed so that the first opening extends over the top surface and both side faces of the center portion.

Abstract: A near-field light source device including a semiconductor laser comprised of laminated semiconductor layers and having a ring-type optical resonator with a plurality of wave guides connected via mirror portions, a light blocking film formed in one of the mirror portions and having a small opening not greater than a wavelength size, and a diffraction grating formed on the light blocking film. The light oscillated from the semiconductor laser is diffracted by the diffraction grating, the diffracted light is coupled to a rotation mode in the ring-type optical resonator, and near-field light is generated via the small opening.

Abstract: A semiconductor laser beam device, comprising a stem type package having a base part and a heat sink part, wherein the heat sink part is cylindrically formed so as to be concentric to the base part, a groove is formed along the axial direction of the heat sink part, and a semiconductor laser beam element is disposed at the bottom part of the inner wall surfaces of the groove whereby the radiating capability of the semiconductor laser beam device can be increased by increasing the volume of the heat sink part, and the element can be protected by the groove.

Abstract: Disclosed is a laser module case having a snout disposed within a wall of the case, wherein the snout may allow alignment of a laser with an optical fiber after closure of the case. The snout has an inner end, outer end and longitudinal hollow. An optical fiber assembly, also with an inner end, outer end and longitudinal hollow, is disposed within the snout hollow. An inner flange secures the snout to the optical fiber assembly at their inner ends and an outer flange secures the snout to the optical fiber assembly at their outer ends. The optical fiber assembly is of a smaller cross-sectional diameter than the snout hollow so that it may move in an X and Y-direction. The optical fiber assembly may be aligned with a laser positioned within the case after the case is closed. The aligned fiber assembly may then be secured in position by the outer flange.