Abstract: A nitride semiconductor laser including a laminate that includes an n-side semiconductor layer, an active layer and a p-side semiconductor layer, the n-side semiconductor layer or p-side semiconductor layer including a current blocking layer 30 that is made of InxAlyGa1-x-yN (0≦x≦0.1, 0.5≦y≦1, 0.5≦x+y≦1) and has a stripe-shaped window 32 formed therein to pass current flow.

Abstract: A ridge waveguide semiconductor laser diode is disclosed that comprises an n-type semiconductor layer, a p-type semiconductor layer having a ridge forming a waveguide and an active layer disposed between the n-type semiconductor layer and the p-type semiconductor layer. The laser diode also includes a first protective insulating layer partially covering the ridge so as to expose at least a portion of a top face of the ridge, a p-side ohmic electrode in ohmic contact with the portion of the ridge, a p-side pad electrode disposed so as to electrically connect to the p-side ohmic electrode; and an intermediate layer is disposed between the p-side ohmic electrode and the p-side pad electrode so as to cover a portion of the p-side ohmic electrode including an area that covers the top face of the ridge. The intermediate layer can be a diffusion prevention layer for preventing diffusion of a low melting point.

Abstract: A laser device having at least a semiconductor laser element, a window allowing light emitted from the emission end face of the semiconductor laser element to pass therethrough, a photodetector detecting a portion of emitted light reflected from the window that is not being transmitted, and a stem whereon the semiconductor laser element and the photodetector are installed. The window is disposed vertically above the semiconductor laser element. The photodetector is placed at an angle with respect to a horizontal plane and is located contiguous with the main surface of the stem. The laser device is capable of maintaining a stable APC drive regardless of the deterioration of the semiconductor laser element that may occur from continuous oscillation for a long time.

Abstract: A semiconductor laser device comprises a laminate consisting of a semiconductor layer of first conductivity type, an active layer and a semiconductor layer of second conductivity type, which is different from the first conductivity type, that are stacked in order, with a waveguide region being formed to guide a light beam in a direction perpendicular to the direction of width by restricting the light from spreading in the direction of width in the active layer and in the proximity thereof, wherein the waveguide region has a first waveguide region and a second waveguide region, the first waveguide region is a region where light is confined within the limited active layer by means of a difference in the refractive index between the active layer and the regions on both sides of the active layer by limiting the width of the active layer, and the second waveguide region is a region where the light is confined therein by providing effective difference in refractive index in the active layer.

Abstract: This invention aims at improving the breeding activity of boars, especially at preventing the reduction of fertilization capacity in the hot season. Particularly, this invention provides a method for improving the breeding activity of boars with the use of a feed for breeding boars which contains saccharides mainly composed of oligosaccharides.