A semiconductor optical element includes: a first conductivity type semiconductor substrate; and a laminated body disposed on the first conductivity type semiconductor substrate. The laminated body includes, in the following order from a side of the first conductivity type semiconductor substrate: a first conductivity type semiconductor layer; an active layer; a second conductivity type semiconductor layer; and a second conductivity type contact layer. The second conductivity type semiconductor layer includes: a carbon-doped semiconductor layer in which carbon is doped as a dopant in a compound semiconductor; and a group 2 element-doped semiconductor layer in which a group 2 element is doped as a dopant in a compound semiconductor. The carbon-doped semiconductor layer is disposed at a position closer to the active layer than the group 2 element-doped semiconductor layer.

A laser radar includes: a light source including a laser diode; an optical system configured to shape laser light emitted from the laser diode, into a line beam that is long in one direction, and project the line beam to a target area; and a scanner configured to perform scanning with the line beam in a short side direction of the line beam. The laser diode is disposed such that a fast axis of the laser diode extends along a direction corresponding to the short side direction of the line beam.

Edge-emitting laser diodes having mirror facets include passivation coatings that are conditioned using an ex-situ process to condition the insulating material used to form the passivation layer. An external energy source (laser, flash lamp, e-beam) is utilized to irradiate the material at a given dosage and for a period of time sufficient to condition the complete thickness of passivation layer. This ex-situ laser treatment is applied to the layers covering both facets of the laser diode (which may comprise both the passivation layers and the coating layers) to stabilize the entire facet overlay. Importantly, the ex-situ process can be performed while the devices are still in bar form.

A high-order Bragg grating single-mode laser array. The laser array is capable of performing a variety of fixed channel spacings ranging from 25 GHz to 800 GHz. The laser array from bottom to top includes an active layer interposed between a first semiconductor confinement layer with the first conductivity type doping corresponding to the substrate, and a second semiconductor confinement layer with the second conductivity type doping corresponding to an Ohmic contact layer, an insulating film on the main surface side of the semiconductor substrate except for the upper surface of the ridge, and a second electrode which is disposed on the insulating film and contacts the Ohmic contact layer located upper the semiconductor confinement layer with the second conductivity type. The semiconductor laser array includes N semiconductor laser diodes, where N is an integer greater than one.

An integrated semiconductor optical amplifier-laser diode (SOA-LD) device includes a laser diode (LD) section fabricated on a substrate, a semiconductor optical amplifier (SOA) section fabricated on the substrate adjacent to the LD section; and a trench formed at least partially between the LD section and SOA section to electrically isolate the LD section and the SOA section while maintaining optical coupling between the LD section and the SOA section.

A semiconductor optical device includes an element structure layer that includes a mesa stripe extending in a first direction; an electrode film that covers at least an upper surface of the mesa stripe; an electrode pad portion that covers a part of a first region positioned in a second direction, intersecting the first direction, relative to the mesa stripe on an upper surface of the element structure layer and is electrically connected to the electrode film; a first dummy electrode that covers another part of the first region and is electrically insulated from the electrode film; and a second dummy electrode that covers at least a part of a second region positioned in a third direction, opposite to the second direction, relative to the mesa stripe on the upper surface of the element structure layer and is electrically insulated from the electrode film, wherein the first dummy electrode includes a first portion disposed in the first direction relative to the electrode pad portion and a second portion disposed in a fourth direction, opposite to the first direction, relative to the electrode pad portion.

A method for manufacturing a surface emitting laser made of a group-III nitride semiconductor by an MOVPE method includes: (a) of growing a first cladding layer of a first conductive type on a substrate; (b) of growing a first optical guide layer of the first conductive type on the first cladding layer; (c) of forming holes having a two-dimensional periodicity in a plane parallel to the first optical guide layer, in the first optical guide layer by etching; (d) supplying a gas containing a group-III material and a nitrogen source and performing growth to form recessed portions having a facet of a predetermined plane direction above openings of the holes, thereby closing the openings of the holes; and (e) of planarizing the recessed portions by mass transport, after the openings of the holes have been closed, wherein after said the planarizing, at least one side surface of the holes is a {10-10} facet.

In a semiconductor laser device, a semiconductor layer includes a first groove formed on both sides of a ridge, a pair of second recesses facing each other and between which the ridge is interposed on a side of a light emitting surface, and a pair of third grooves in parallel to the first groove from the light emitting surface and interposing the ridge therebetween.

A semiconductor laser element includes: a substrate; a first-conductivity-type semiconductor layer formed on the substrate; a light-emitting layer formed on the first-conductivity-type semiconductor layer; a second-conductivity-type semiconductor layer that is formed on the light-emitting layer and includes a protrusion in a strip form; a transparent conductive layer formed on the protrusion of the second-conductivity-type semiconductor layer; a protective layer that is formed on the transparent conductive layer and has conductivity; a dielectric film that covers side surfaces of the protrusion of the second-conductivity-type semiconductor layer, side surfaces of the transparent conductive layer, and side surfaces of the protective layer; and an upper electrode formed on the protective layer. The whole of an upper surface of the transparent conductive layer is covered by the protective layer, and part of an upper surface of the protective layer is covered by the dielectric film.

Edge-emitting laser diodes having mirror facets include passivation coatings that are conditioned using an ex-situ process to condition the insulating material used to form the passivation layer. An external energy source (laser, flash lamp, e-beam) is utilized to irradiate the material at a given dosage and for a period of time sufficient to condition the complete thickness of passivation layer. This ex-situ laser treatment is applied to the layers covering both facets of the laser diode (which may comprise both the passivation layers and the coating layers) to stabilize the entire facet overlay. Importantly, the ex-situ process can be performed while the devices are still in bar form.