摘要:
Semiconductor lasers are driven such that high output laser beams are stably obtained without a long start up time. A method for driving semiconductor lasers by automatic current control or automatic power control with a constant current source involves the steps of: generating a pattern of drive current values for the semiconductor lasers, which is defined according to the amount of time which has elapsed since initiating driving thereof, that enables obtainment of substantially the same light output as a target light output by the automatic current control or the automatic power control; and varying the drive current of the semiconductor lasers in stepwise increments according to the pattern for a predetermined period of time from initiation of drive thereof. A single pattern is used in common to drive the plurality of semiconductor lasers.
摘要:
A surface-emitting semiconductor array device includes a substrate, a plurality of light-emitting portions, an electrode pad portion formed on the substrate and disposed through the plurality of light-emitting portions and a dividing groove, and having a plurality of electrode pads formed on an insulating film, and a plurality of metal wirings for connecting each of the plurality of light-emitting portions to a corresponding electrode pad through the dividing groove, the dividing groove has a wave-shaped side wall formed on the substrate.
摘要:
An optically stacked, laser diode array module (10) includes a mounting block (100) having a series of stepped, parallel diode mounting surfaces (101) on one face of the block, each diode mounting surface cooperating with a respective pair of reference surfaces (102, 103) of the block to form a respective outside block corner, a series of laser diodes (300) affixed to the block, with facets of the diode aligned with the reference surfaces forming the outside block corner with the mounting surface on which the diode is disposed, such that a corner of each diode is aligned with a respective corner of the block, and a beam reflector (200) secured to the block and having a series of stepped, parallel surfaces, each positioned to intercept and reflect a respective one of the beams (500) from the laser diodes, such that the reflected beams are parallel and stacked. The beams (500) emitted from the laser diodes (300) can be collimated by microlenses (400).
摘要:
A highly compact laser scanner with no moving parts includes a vertical cavity surface emitting laser (VCSEL). A microlens is mounted directly to the light emitting surface of the VCSEL via flip chip bonding. The VCSEL array may be one or two dimensional. The laser array may be used in a variety of applications including free space optical communications.
摘要:
A semiconductor laser apparatus for broad-angle far-field addressing is disclosed. The apparatus comprises a laser block with lasing cavities. The lasing cavity mirrors are made by dry-etching of the semiconductor block. The width of a lasing cavity is defined by a p contact pad on the laser block; further lateral confinement of current to the cavity is achieved by proton implantation followed by etching of the proton layer. The apparatus achieves quasi-continuous beam steering with a total steering angle of 80.degree. and with 11 resolvable spots.
摘要:
A monolithic integrated master oscillator power amplifier (MOPA) device including a single mode diode laser with distributed Bragg reflectors, an amplifier in tandem with the laser, lateral phase controllers and a detuned second order grating surface output coupler, all on a common substrate. The amplifier is a flared waveguide in one embodiment, and a branching network of single mode waveguides followed by an array of single mode gain waveguides in another embodiment. The diode laser is tunable by means of a separate tuning current applied to the rear Bragg reflector. Tuning the laser wavelength provides, in conjunction with the output coupler, a longitudinal steering of the output beam. The lateral phase controllers are an array of separately addressable electrodes that adjust the optical path length to compensate for phase variation in the amplifiers and also to provide lateral steering of the output beam. An additional embodiment includes a chain of amplifiers and grating output couplers for providing multiple output beams.
摘要:
The present invention relates to phased-array semiconductor lasers having a radiation angle turnable by oscillating independently and stably between the fundamental supermode and the higher order supermode and switching the radiation angles by utilizing the property that their radiation angles are different.Optical switching and optical scanning, that have been difficult in the prior art, can be made more easily by use of a semiconductor laser having a turnable radiation angle.The objection of the present invention can be accomplished by disposing separate electrodes at the emission stripes and at the gap between the stripes in the phased-array semiconductor laser.Further, the present invention may be accomplished by dividing at least one stripe electrode in order to form electrode regions. When the current is applied to all the electrodes, oscillation occurs in the highest order mode and the beam is emitted in another direction. When the current is applied to only the electrode exclusive of the electrode regions, oscillation occurs in the fundamental mode and the beam is emitted in a direction vertical to a facet.Moreover, the present invention may be accomplished by disposing electrodes outside the stripe regions of the phased-array semiconductor laser so that oscillation occurs in the fundamental supermode when the electric field is applied to the electrodes and in the higher order mode when the electric field is not applied.
摘要:
An optical scanner with a thin waveguide medium on a substrate includes means to couple a wide collimated beam of radiation into one end of the medium. A periodic array of substantially parallel, spaced electrodes are associated with one major surface of the medium. At least a portion of their electrode lengths extend in a direction substantially parallel with the direction of radiation propagating through the medium. Supply means is provided to apply voltages in a pattern to the electrodes which varies from one electrode to the next adjacent electrode to a predetermined value over several of the electrodes and the same pattern of voltages or a similar pattern of different voltages is applied over several of the next adjacent electrodes up to the predetermined value. In this manner, the pattern is completed across the electrode array to produce a corresponding approximation of a desired phase retardation along a phase front of the propagating radiation in the medium. Further means is employed to change the magnitude of the applied voltages across the electrode array to vary the approximation of the phase retardation to cause the radiation beam to scan in a direction of radiation propagation in the medium.
摘要:
Apparatus, systems and methods to spectrally beam combine a group of diode lasers in an external cavity arrangement. A dichroic beam combiner or volume Bragg grating beam combiner is placed in an external cavity to force each of the diode lasers or groups of diode lasers to oscillate at a wavelength determined by the passband of the beam combiner. In embodiments the combination of a large number of laser diodes in a sufficiently narrow bandwidth to produce a high brightness laser source that has many applications including as to pump a Raman laser or Raman amplifier.
摘要:
Provided are systems and methods for high-dimensional phase-locked microlaser arrays. In embodiments, systems and methods can comprise a main array of light sources resonating in a plurality of energy levels, including a fundamental mode, at least one superpartner array of resonators positioned adjacent to the main array, and at least one auxiliary resonator. The superpartner arrays and the auxiliary resonators at least partially dissipate a subset of the plurality of energy levels emitted by the main array, except for the fundamental mode. In embodiments, the light sources can be microring lasers and/or electrically injected lasers.