Abstract: A laser diode includes a substrate, a lower cladding layer or a lower optical waveguide layer substantially free from Al and provided on the substrate, an active layer of a mixed crystal containing Ga and In as a group III element and N, As and/or P as a group V element, provided on the lower cladding layer; and an upper cladding layer or an upper optical waveguide layer substantially free from Al and provided on the active layer.

Abstract: A semiconductor laser emits light through a front end and a rear end, the front end being coupled to an application system. The front end has a higher reflectivity than the rear end, to reduce problems caused by returning light. More light is therefore emitted through the rear end than through the front end. In a light source, the light emitted through the rear end is monitored by an optical detector coupled to a control circuit, which controls the voltage applied to the semiconductor laser.

Abstract: Coherent light sources combining a semiconductor optical source with a light diverging region, such as a flared resonator type laser diode or flared amplifier type MOPA, with a single lens adapted to correct the astigmatism of the light beam emitted from the source is disclosed. The lens has an acircular cylindrical or toroidal first surface and an aspheric or binary diffractive second surface. The first surface has a curvature chosen to substantially equalize the lateral and transverse divergences of the astigmatic beam. Sources with an array of light diverging regions producing an array of astigmatic beams and a single astigmatism-correcting lens array aligned with the beams are also disclosed. The single beam source can be used in systems with frequency converting nonlinear optics. The array source can be stacked with other arrays to produce very high output powers with high brightness.

Abstract: A surface-type optical device, such as a surface emitting laser device, includes a first substrate, a plurality of active regions formed and disposed on the first substrate, and a control unit for injecting a current into or applying an inverse voltage to each active region. A portion of the first substrate is removed over an area including at least two active regions. The active region is constructed such that light is output from or input into each active region perpendicularly to the first substrate. A second substrate may be bonded to a side of the epitaxially-grown layers of the first substrate.

Abstract: An integrated semiconductor laser produced by forming waveguide layers each having a particular band gap and a particular layer thickness collectively and then forming an InP current blocking layer. After an InGaAsP layer has been formed on an InP substrate, a waveguide including a multiple quantum well active layer is formed by selective MOVPE. Then, the waveguide is buried in an InP current blocking layer. In this configuration, the current blocking layer exhibits its expected function without regard to the width of SiO2 stripes used for selective metalorganic vapor phase epitaxial growth (MOVPE). The laser is feasible for high output operation and can be produced at a high yield.

Abstract: External cavity micro laser apparatus comprises at least one multimode micro laser having an emission aperture with a relatively long dimension lying in a slow axis plane and a relatively short dimension lying in a fast axis plane. The laser produces multiple transverse lasing modes, the multiple modes having multiple lasing lobe components. External cavity means embracing the laser has an output section including spatial filter means, which may be the input aperture of an optical waveguide, for effectively selecting at least one of the transverse lasing lobe components. The cavity output section includes imaging means for imaging at the spatial filter means a far field spatial frequency distribution in the slow axis plane of the emission aperture, at which distribution the lasing lobe components are spatially distinguishable.

Abstract: In a semiconductor laser device 100, an n-type InGaAsP light confinement layer 2, a multiple quantum well active layer 3, a p-type InGaAsP light confinement layer 4, and a p-type InP cladding layer 5 are formed on an n-type InP substrate 1 to be in a mesa structure extending in stripes along the cavity length direction. Moreover, regions on both sides of this striped mesa are buried with a p-type InP current blocking layer 6 and an n-type InP current blocking layer 7. Furthermore, a p-type InP burying layer 8 and a p-type InGaAsP contact layer 9 are formed thereon. The oscillation wavelength of the semiconductor laser device 100 is around 1.3 .mu.m. The stripe width of the active layer 3 is such that the width W1 at the front end face and the width W2 at the rear end face have a relationship of W1<W2, and the stripe width is continuously reduced from W2 to W1 along the cavity length direction.

Abstract: A semiconductor laser light source includes: a semiconductor laser array which emits laser beams whose polarization planes are parallel to each other and whose divergent angles .theta.z and .theta.x in two orthogonal directions satisfy an inequality .theta.z>.theta.x; a cylindrical lens which converges the laser beams emitted from the semiconductor laser array in a direction that decreases the divergent angle .theta.z; a wave plate which controls the direction of polarization so that the polarization planes of the laser beams having passed through the cylindrical lens are at 90 degrees to each other; a birefringent optical element which merges by the birefringent effect the optical paths of the laser beams having passed through the wave plate; and a light emitting surface which converges the laser beams merged by the birefringent optical element in a direction that decreases the divergent angle .theta.x.

Abstract: An integrated laser/modulator ("ILM") operating with reduced chirping is formed on a single semiconductor substrate. A reduction in chirping and any resultant wavelength dispersion is realized by precisely controlling the length of a window region incorporated in the ILM in order to isolate the ILM's active regions from any residual reflections.

Abstract: A semiconductor light emission device includes at least an n-type semiconductor clad layer, a semiconductor active layer and a p-type semiconductor clad layer formed on a substrate in this order. A stripe portion which determines a light emission region is formed on a part of the p-type clad layer and a p-type capping layer is formed on the stripe portion. A p-side electrode is formed on the p-type capping layer. The p-type capping layer includes a lower capping layer in the form of a stripe overlaid on the stripe portion and an upper capping layer which is formed on the lower capping layer and has an area larger than that of the lower capping layer. The contact area between the p-side electrode and the upper capping layer of the p-type capping layer is larger than that between the upper capping layer and the lower capping layer of the p-type capping layer.

Abstract: A light generating apparatus includes: a submount; a semiconductor laser chip mounted on the submount; a substrate which is mounted on the submount and includes an optical waveguide; and a substance having a predetermined thickness which is disposed between the semiconductor laser chip and the substrate. In an oscillation wavelength stabilizing apparatus for a light source, the light source is a semiconductor laser which includes: an active region for providing gain; and a distributed Bragg reflection (DBR) region for controlling an oscillation wavelength. The apparatus includes a control section which monotonously varies, in a first direction, a DBR current to be input to the DBR region while detecting the oscillation wavelength of an output light of the semiconductor laser so as to detect a DBR current value I.sub.0 corresponding to a predetermined wavelength value, and then monotonously varies the DBR current in a second direction which is opposite the first direction beyond the detected value I.sub.

Abstract: A II-VI semiconductor device is fabricated using a selective etchant in the form of aqueous solution of HX where X is Cl or Br. The II-VI semiconductor device is composed of a number of layers. Selective etching can be enabled by introducing Mg into one of the semiconductor layers. The resultant device may include a semiconductor layer containing Mg.

Abstract: A semiconductor laser array has an array of a plurality of laser active sections mounted on a submount, with a common p-side electrode sandwiched therebetween. The laser active sections formed on a semiconductor substrate and separated from each other by separation channels are bonded onto the common p-side electrode in a junction-down fashion wherein the top layer of the laser active sections are bonded to the common p-side electrode. The semiconductor substrate are polished at the back surface for separation of the laser active sections from each other, followed by forming an n-side electrode for each of the laser active sections. The semiconductor laser array can be formed in a uniform thickness and can be driven by N-P-N transistor at a high speed.

Abstract: The present invention provides a method, article of manufacture, and optical package (24) for eliminating tilt angle (40) between an optical emitter (26) mounted on a carrier (28). The method, article of manufacture, and optical package (24) include a carrier (28) having a top surface (42) with a cavity (46) formed therein, an adhesive material (38) inserted into the cavity (46), and an optical emitter (26) placed on the top surface (42) of the carrier (28) and at least partially covering the cavity (46), thereby providing at least one egress point for overflowing said adhesive material therefrom.

Abstract: There is provided a mode-locked semiconductor laser including a saturable absorber section, a gain section having the same composition as that of the saturable absorber section, a non-absorptive waveguide section having an absorption edge wavelength shorter than an oscillation wavelength of the gain section, an electroabsorption modulator section having an absorption edge wavelength intermediate between an oscillation wavelength of the gain section and an absorption edge wavelength of the non-absorptive waveguide section, and a distributed Bragg reflector section having the same composition as that of the non-absorptive waveguide section and including a diffraction grating. These five sections are optically coupled to one another in a single waveguide.

Abstract: A mode-locked semiconductor laser includes a gain region formed from a semiconductor gain material of two or three dimensional carrier confinement structure having a size on the order of a thermal de-Broglie wavelength, the size of the semiconductor of the carrier confinement structure being controlled such that the gain spectrum has discrete peaks at a frequency period which is an integer power of the reciprocal of the round-trip time of light in the optical resonator.

Abstract: A composite optical device having a high efficiency of coupling a laser diode and an optical device and a method of producing the composite optical device. The composite optical device connects a laser diode with a first mesa including an active layer on a (001) plane of a compound semiconductor substrate via a first cladding layer and an optical device provided with a second mesa including an optical waveguide layer formed on the (001) plane via a second cladding layer, wherein one end of the active layer and one end of the optical waveguide layer oppose each other at a distance smaller than the thicknesses of the first and second cladding layers. At least the second cladding layer is grown in an ambient supplemented with HCl to produce a planar surface.

Abstract: The invention provides a complex coupled distributed feedback (DFB) semiconductor laser device with energy band gap modulation. The device comprises an active region formed on a substrate, and a barrier region adjacent the active region, the energy band gap of the barrier region modulated along a cavity length direction to form a complex coupled grating. The modal gain is higher in the barrier region areas, having narrower energy band gap, due to higher material gain and higher optical confinement factor in these areas. Periodic modulation of the energy band gap of the barrier region produces gain (or loss) modulation and index modulation in the material of the active region, thus, gain coupling and index coupling mechanisms being provided. Methods of producing gain modulation in the DFB laser, and fabrication thereof are also provided.

Abstract: A laser diode array unit for use in laser beam scanning optical apparatus and the like. The laser diode array has plural light emitting sources to be drivingly controlled independently of each other. The laser diode array is so disposed as to permit laser beams emitted from the light emitting sources to be incident to a collimator lens. On an optical axis between the laser diode array and the collimator lens is disposed a beam splitter for splitting the laser beams emitted from the light emitting sources into image light and monitor light. A magnifier lens and a photoreceptor element are arranged on the optical axis so as to allow incidence of monitor light oriented to advance in a direction perpendicular to the direction of advance of image light.

Abstract: An optical connector system comprises mating first and second fiber ferrules (1, 11). Each ferrule (1, 11) has an endface (4, 14) polished at an angle to minimize backreflections. A holographic optical element (6) disposed on the first ferrule endface (4) receives a transmitted beam and expands the beam to an expanded beam (21) of collimated light. The expanded beam (21) is launched into an air gap (22) for receipt by a holographic optical element (16) disposed on the second ferrule (11). The holographic optical element (16) on the second ferrule (11) receives the expanded beam (21) and focuses it to be received by the fiber held in the second ferrule (11).