Abstract: A laser diode includes an n-type semiconductor region, a p-type semiconductor region, a semiconductor mesa provided between the n-type semiconductor region and the p-type semiconductor region, the semiconductor mesa including an active layer, and a semiconductor burying region located between the n-type semiconductor region and the p-type semiconductor region, the semiconductor burying region being provided on a side face of the semiconductor mesa. The semiconductor burying region includes an n-type semiconductor burying layer and a p-type semiconductor burying layer. The n-type semiconductor burying layer is provided between the p-type semiconductor region and the p-type semiconductor burying layer. The p-type semiconductor burying layer is doped with an element that forms an electron trapping level in the band gap of the p-type semiconductor burying layer.

Abstract: The invention relates to a radiation-emitting semiconductor chip, comprising an active zone for generating radiation having a wavelength lambda and a structured region having irregularly arranged structure elements which contain a first material having a first refractive index n1 and which are surrounded by a medium comprising a second material having a second refractive index n2. A method for producing a semiconductor chip of this type is furthermore specified.

Abstract: The invention relates to an edge-emitting semiconductor laser comprising a semiconductor body (10), which comprises a waveguide region (4), wherein the waveguide region (4) comprises a first waveguide layer (2A), a second waveguide layer (2B) and an active layer (3) arranged between the first waveguide layer (2A) and the second waveguide layer (2B) and serving for generating laser radiation (5), and the waveguide region (4) is arranged between a first cladding layer (1A) and a second cladding layer (1B) disposed downstream of the waveguide region (4) in the growth direction of the semiconductor body (10).

Abstract: A surface emitting semiconductor laser includes a first semiconductor layer sequence, which comprises a pump laser. A second semiconductor layer sequence is arranged on the first semiconductor layer sequence and comprises a vertical emitter. The vertical emitter has a radiation-emitting active layer, a radiation exit side and a connecting side lying opposite the radiation exit side. The pump laser is arranged at the radiation exit side of the vertical emitter and a carrier body is arranged at the connecting side of the vertical emitter. Furthermore, a method for producing a surface emitting semiconductor laser is specified.

Abstract: In an optical disk apparatus, by obtaining the temperature in the vicinity of a laser in the apparatus, the power source voltage of the laser driver is controlled such that power consumed by the headroom of the laser driver is reduced to the maximum extent without deteriorating the current drive characteristic of the headroom when the temperature becomes higher. The laser driving current of the laser driver is monitored to control the power source of the laser driver such that the power consumed by the headroom is possibly reduced while maintaining the current drive characteristic of the headroom for the monitored current.

Abstract: Preferred embodiments of a purge gas port, laser beam attenuating input window, and laser shutter constitute subsystems of a UV laser optical system in which a laser beam is completely enclosed to reduce contamination of the optical system components. Purge gas is injected through multiple locations in a beam tube assembly to ensure that the optical component surfaces sensitive to contamination are in the flow path of the purge gas. The input window functions as a fixed level attenuator to limit photopolymerization of airborne molecules and particles. Periodically rotating optical elements asymmetrically in their holders reduces burn damage to the optics.

Abstract: Schemes are provided for starting up optical transmission links where, after a link interruption, endpoints switch into a startup mode original detection state, and a query-transmit pulse goes out at both end points at given time intervals. In a “TRANSMITTED” handshake mode, in a loop to be passed through n times, and at least once, after the transmission of a transmit pulse, it is detected whether a received pulse is received within a given time span. If no received pulse is received, then the mode is ended and the system is returned to the original detection state. If a received pulse is received, it is answered with another transmit pulse. After the last transmit pulse, if another received pulse occurs within a given time span, the link is activated. If not, the “TRANSMITTED” handshake mode ends and the system enters the original detection state.

Abstract: A laser irradiation system includes a laser configured to irradiate light, a laser transfer unit configured to transfer the laser along a target irradiation area, the target irradiation area being divided into a plurality of sections, a laser transfer controller configured to control a speed of the laser in each of the plurality of sections of the target irradiation area, a laser output controller configured to control an output level of the laser in each of the plurality of sections of the target irradiation area, and a main controller configured to control the laser output controller and the laser transfer controller.

Abstract: A high power (HP) fiber circulator is configured with a case enclosing a plurality of optical components which are arranged so as to define multiple ports. The fiber circulator further includes a plurality of launching and receiving fiber components each of which has spliced delivery and pigtailed passive fibers selectively coupling a HP input signal into and receiving a HP output signal from respective input and output ports. The passive fibers of each fiber component have respective protective coatings spaced from one another and each covering the cladding of the fibers. A light stripper, extending between the protective coatings, is operative to substantially remove cladding-supported light from one of the passive fibers before it reaches the protective coating of the other passive fiber.

Abstract: The invention relates to a modulation scheme for optical communication, in particular for fiber optics communication. According to invention, an optical signal is generated, both phase and polarization of which modulated in dependency of the data to be transmitted. Preferably, the generated optical signal comprises a sequence of symbols (22a-22k) and each symbol (22a-22k) has one of two different phase states and one of two different orthogonal polarization states. Bits of the data stream to be transmitted are encoded both in the phase state of a symbol (or in the phase state difference between subsequent symbols) and in the polarization state of the symbol (or in the polarization state difference between the subsequent symbols).

Abstract: A header assembly for extended temperature optical transmitters is disclosed. The header assembly may include a hermetic enclosure and a header base with an interior surface. A plurality of conductive leads penetrate from the outer portion of the header assembly to the interior surface. A thermoelectric cooler (“TEC”) having a planar configuration and a thickness not exceeding 500 microns is positioned adjacent to the interior surface of the header assembly, the TEC being in thermal communication with the header base and a mounting surface. A submount, on which a laser diode is positioned, is in thermal communication with the mounting surface of the TEC. In this manner, the TEC may be configured affect a selective transfer of heat to the laser diode and transfer of heat away from the laser diode. In some embodiments, the header assembly is configured to operate at optical data transmission rates of 10 Gbps or higher in such extended ambient temperatures.

Abstract: An optical apparatus comprising a gain medium exhibiting polarisation dependent absorption along two axes, the gain medium having a weakly absorbing axis and a strongly absorbing axis, an optical pump source arranged to direct pump light towards a first face of the gain medium such that the pump light entering the gain medium has a component of its polarisation parallel to the weakly absorbing axis, a polarisation modifying apparatus and one or more reflectors which are together arranged to modify the polarisation of pump light which exits the gain medium through a second face of the gain medium, and to direct the pump light with modified polarisation back towards said second face of the gain medium.

Abstract: A laser device with frequency conversion, the device comprising a complex optical cavity comprising two cavity parts with two different levels of circulating intracavity power wherein there is placed at least one non-linear crystal (30) is placed within the cavity part of higher circulating power and an active medium (21) in the cavity part of lower circulating power, the power enhancement achieved in two steps and the total enhancement being the product of the enhancement factors in each step, providing additional freedom in design allowing both the condition for high enhancement of the interacting laser power inside the intracavity non-linear crystal and the condition for maximum power output from the laser to be satisfied simultaneously and wherein said complex optical cavity the first cavity part provides the initial step of power enhancement and comprises at least a laser cavity back mirror (20), highly reflective about a laser radiation fundamental frequency .omega., and an active (gain) medium.

Abstract: A multiwavelength laser system for opthalmological applications. The system including a first semiconductor diode laser including a first working beam of a first wavelength; and at least one second semiconductor diode laser having a second working beam of a second wavelength. The second wavelength being different from the first wavelength.

Abstract: A light emitting device includes: a single crystal substrate having a plane tilted from a low-index plane and first and second cladding layers sandwiching an active layer, wherein the active layer includes first and second parallel side surfaces, part of the active layer constitutes first and second gain regions, a first side surface reflectance is higher than a second side surface reflectance, each of the first and second gain regions is disposed from a first side surface end surface to a second side surface end surface, the first gain region end surface partially overlaps the second gain region end surface so the end surfaces do not overlap each other in the first and second gain regions, a perpendicular of the first side surface is parallel to an off-direction of the substrate, and the first and second gain regions have equal lengths.

Abstract: External cavity laser (ECL) systems and methods for measuring the wavelength of the ECL by using a portion of the positional light received by the position sensitive detector (PSD) to determine the position of a wavelength tuning element (such as a diffraction grating or an etalon), for determining the longitudinal laser mode or power output of the laser from a portion of the laser light received by a beam-shearing mode sensor, and by using a non-output beam(s) from a transmissive diffraction grating in the ECL to monitor the external cavity laser.

Abstract: A wavelength tunable laser includes a DFB portion including a first optical waveguide provided with a first grating; a DBR portion including a second optical waveguide that is optically coupled to the first optical waveguide and is provided with a plurality of second gratings continuously arranged in a waveguide direction; and a phase shift portion including a third optical waveguide that is optically coupled to the first and second optical waveguides. Each of the second gratings has a grating formation area in which a grating is formed, and a grating phase shift area which shifts the phase of the grating adjacent thereto in the second grating.

Abstract: A laser apparatus comprises an amplifier including at least one of a MOPA and a MOPO each of which amplifies a single-longitudinal or multiple-longitudinal mode laser light, an amplifiable agent of the amplifier being a molecular gas, a master oscillator constructed from a semiconductor laser being able to oscillate a single-longitudinal or multiple-longitudinal mode laser light of which wavelength is within one or more amplification lines of the amplifier; and a controller executing a wave shape control adjusting a pulse shape and/or a pulse output timing of a single-longitudinal or multiple-longitudinal mode laser light outputted from the master oscillator.

Abstract: Various example embodiments are disclosed. According to one example embodiment, a phase error is estimated in a series of digital symbols of a phase-modulated signal, where the signal is subject to a non-linear phase shift error due to transmission of the signal through an optical fiber. A phase correction of an instant digital symbol that succeeds the series of digital symbols is estimated, where the estimated phase correction is based on the estimated phase errors in the series of digital symbols. The estimated phase correction of the instant digital symbol is limited to a maximum absolute value, and the estimated phase correction is applied to the instant digital symbol of the signal.

Abstract: A laser source assembly (10) for providing an assembly output beam (12) includes a first MIR laser source (352A), a second MIR laser source (352B), and a beam combiner (244). The first MIR laser source (352A) emits a first MIR beam (356A) that is in the MIR range and the second MIR laser source (352B) emits a second MIR beam (356B) that is in the MIR range. Further, the beam combiner (244) spatially combines the first MIR beam (356A) and the second MIR beam (356B) to provide the assembly output beam (12). With this design, a plurality MIR laser sources (352A) (352B) can be packaged in a portable, common module, each of the MIR laser sources (352A) (352B) generates a narrow linewidth, accurately settable MIR beam (356A) (356B), and the MIR beams (356A) (356B) are combined to create a multiple watt assembly output beam (12) having the desired power. The beam combiner (244) can includes a combiner lens (364) and an output optical fiber (366).