Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) capable of providing high output of fundamental transverse mode while preventing oscillation of high-order transverse mode is provided. The VCSEL includes a semiconductor layer including an active layer and a current confinement layer, and a transverse mode adjustment section formed on the semiconductor layer. The current confinement layer has a current injection region and a current confinement region. The transverse mode adjustment section has a high reflectance area and a low reflectance area. The high reflectance area is formed in a region including a first opposed region opposing to a center point of the current injection region. A center point of the high reflectance area is arranged in a region different from the first opposed region. The low reflectance area is formed in a region where the high reflectance area is not formed, in an opposed region opposing to the current injection region.

Abstract: A tilted wave semiconductor diode laser containing additional structural elements that improve beam quality is provided. The tilted wave laser includes a narrow active waveguide coupled to a broad passive waveguide, and light generated in the active waveguide leaks to the broad waveguide and propagates in it in the form of a tilted optical wave. The device emits laser light coming out from the broad waveguide in the form of one or two narrow beams. The additional structural elements may include grooves intersecting the narrow waveguide and a stripe that suppress undesired emission from the narrow waveguide; grooves that extend parallel to the stripe that suppress parasitic lateral optical modes; unpumped sections of the stripe that suppress light emission from the narrow waveguide; and facet coatings having distinct reflectance for the light in the narrow and in the broad waveguides thus suppressing emission of light from the narrow waveguide.

Abstract: A method to control an LD (laser diode) is disclosed. The method compares the operating temperature of the LD with a transition temperature. When the former temperature exceeds the latter, the modulation current is set based on the bias current, which is independently determined by the APC loop. On the other hand, the operating temperature is less than the transition temperature; the modulation current is determined by the operating temperature.

Abstract: To reduce the laser threshold by efficiently exciting a light-emitting body in a solid-state dye laser with light having high density, thereby facilitating emission of laser beams, and to miniaturize a solid-state dye laser including an excitation light source. A solid-state dye laser capable of emitting laser beams by efficiently introducing light from an excitation light source to a light-emitting body incorporated in an optical resonator structure and exciting the light-emitting body with light with high density, is realized.

Abstract: A fiber laser device includes a pumping light source configured to output pumping light having a wavelength ?, and a rare earth-doped fiber, wherein when the intensity change rate of the pumping light with respect to the temperature is denoted by ?P dB/° C., the wavelength change rate of the pumping light with respect to the temperature is denoted by ??p nm/° C., the pumping light absorption change rate of the rare earth-doped fiber per unit wavelength change at the wavelength of ? nm when the wavelength of the pumping light changes is denoted by A?(?) dB/nm, and the pumping light absorption change amount of the rare earth-doped fiber per unit temperature change at the wavelength of ? nm when the temperature of the rare earth-doped fiber changes is denoted by ?A(?) dB/° C., the wavelength ? of the pumping light is such a wavelength ? that ?P, ??p×A?(?) and ?A(?) compensate with each other.

Abstract: A laser and electroabsorption modulator (EAM) are monolithically integrated through an etched facet process. Epitaxial layers on a wafer include a first layer for a laser structure and a second layer for an EAM structure. Strong optical coupling between the laser and the EAM is realized by using two 45-degree turning mirrors to route light vertically from the laser waveguide to the EAM waveguide. A directional angled etch process is used to form the two angled facets.

Abstract: A control system and apparatus for use with an ultra-fast laser is provided. In another aspect of the present invention, the apparatus includes a laser, pulse shaper, detection device and control system. A multiphoton intrapulse interference method is used to characterize the spectral phase of laser pulses and to compensate any distortions in an additional aspect of the present invention. In another aspect of the present invention, a system employs multiphoton intrapulse interference phase scan. Furthermore, another aspect of the present invention locates a pulse shaper and/or MIIPS unit between a laser oscillator and an output of a laser amplifier.

Abstract: Laser light wavelength control is provided by periodically predicting a next position of a light controlling prism using a model of the prism's motion characteristics. The prediction is then updated if a measurement of laser output wavelength is obtained. However, because the predictions are made without waiting for a measurement, they can be made more frequently than the laser firing repetition rate and the prism can be repositioned at discrete points in time which can occur more frequently than the laser firing events. This also reduces performance degradation which may be caused by being one pulse behind a laser measurement and the resultant laser control signal being applied.