Abstract: A semiconductor light emitting device includes a light emitting unit, a first and second conductive pillar, a sealing unit, a translucent layer, and a wavelength conversion layer. The light emitting unit includes a first and second semiconductor layer and a light emitting layer. The first semiconductor layer has a first and second major surface. The first major surface has a first and second portion. The second major surface is opposed the first major surface and has a third and fourth portion. The light emitting layer is provided on the first portion. The second semiconductor layer is provided on the light emitting layer. The first conductive pillar is provided on the second portion. The second conductive pillar is provided on the second semiconductor layer. The translucent layer is provided on the fourth portion. The wavelength conversion layer is provided on the third portion and on the translucent layer.

Abstract: A semiconductor light emitting device includes a light emitting unit, a first and second conductive pillar, a sealing unit, a translucent layer, and a wavelength conversion layer. The light emitting unit includes a first and second semiconductor layer and a light emitting layer. The first semiconductor layer has a first and second major surface. The first major surface has a first and second portion. The second major surface is opposed the first major surface and has a third and fourth portion. The light emitting layer is provided on the first portion. The second semiconductor layer is provided on the light emitting layer. The first conductive pillar is provided on the second portion. The second conductive pillar is provided on the second semiconductor layer. The translucent layer is provided on the fourth portion. The wavelength conversion layer is provided on the third portion and on the translucent layer.

Abstract: The present invention provides a semiconductor laser element, a method of fabrication thereof, and a multi-wavelength monolithic semiconductor laser device that achieve self-sustained pulsation up to a high output level and achieve self-sustained pulsation over a wide output range.

Abstract: A semiconductor laser device comprises: a cladding layer of a first conductivity type; an active layer provided on the cladding layer; and a cladding layer of a second conductivity type provided on the active layer. At least a part of the cladding layer of the second conductivity type has a ridge stripe. The ridge stripe includes: an upper part having substantially vertical sidewalls; and a lower portion having sidewalls inclined so that the stripe becomes wider toward the active layer.

Abstract: A semiconductor laser device comprises: a cladding layer of a first conductivity type; an active layer provided on the cladding layer; and a cladding layer of a second conductivity type provided on the active layer. At least a part of the cladding layer of the second conductivity type has a ridge stripe. The ridge stripe includes: an upper part having substantially vertical sidewalls; and a lower portion having sidewalls inclined so that the stripe becomes wider toward the active layer.

Abstract: The present invention provides a semiconductor laser element, a method of fabrication thereof, and a multi-wavelength monolithic semiconductor laser device that achieve self-sustained pulsation up to a high output level and achieve self-sustained pulsation over a wide output range.

Abstract: A semiconductor laser array including a plurality of index-guided semiconductor lasers different in oscillation wavelength is made by collectively controlling their double transverse modes and collectively processing them to form their current-blocking structures and buried layers. Thus, a semiconductor laser having a flat element surface and excellent in heat radiation can be made in a reduced number of manufacturing steps. When the laser array of this multi-wavelength type and a detector PD are mounted with a predetermined positional relationship, return light from an optical disk can be converted into a single point to enable detection thereof at PD on one chip. Therefore, an optical disk driving apparatus remarkably reduced in size and weight and having a high reliability can be realized.

Abstract: A semiconductor laser array including a plurality of index-guided semiconductor lasers different in oscillation wavelength is made by collectively controlling their double transverse modes and collectively processing them to form their current-blocking structures and buried layers. Thus, a semiconductor laser having a flat element surface and excellent in heat radiation can be made in a reduced number of manufacturing steps. When the laser array of this multi-wavelength type and a detector PD are mounted with a predetermined positional relationship, return light from an optical disk can be converted into a single point to enable detection thereof at PD on one chip. Therefore, an optical disk driving apparatus remarkably reduced in size and weight and having a high reliability can be realized.

Abstract: This is a double wavelength semiconductor laser unit having a first laser emitting a light of a first wavelength and a second laser emitting a light of a second wavelength different from the first wavelength. The first and second lasers are merged on a substrate. The first laser has a bulk active layer whose film thickness is 0.01 &mgr;m or more and 0.1 &mgr;m or less. And the second laser has an MQW active layer constituted by stacked structure composed of a quantum well layer and a barrier layer. By employing the bulk active layer for the first laser, it is possible to reduce the band gap discontinuity induced at a boundary between a cladding layer and the bulk active layer, and then decreases an operational voltage, and further improve the reliability of the first laser.

Abstract: Inhibiting an reflective coating of a semiconductor laser from peeling. In addition to a p-InGaAlP ridge-stripe optical waveguide layer 6, a p-InGaAlP ridge-stripe 6a is formed on a p-InGaP etching stopper layer 5. Thereby, non-optical-waveguide swellings 13a are formed on both sides of an optical waveguide swelling 13.

Abstract: The present invention provides an air filter that is excellent in anti-molding and anti-bacterial functions. The anti-mold and anti-bacteria air filter is formed from fabric knitted and woven with a warp and/or a weft made of filiform thermoplastic resin including the organic anti-molding agent and filiform thermoplastic resin including the inorganic anti-bacterial agent. It is also possible to form multi-woven fabric knitted and woven with a warp made of filiform thermoplastic resin including the organic anti-molding agent and the filiform thermoplastic resin including the inorganic anti-bacterial agent.

Abstract: An InGaAlP NAM structure laser is formed with a double-heterostructure section disposed on an n-type GaAs substrate. The double-heterostructure section includes a first cladding layer of n-type InGaAlP, a non-doped InGaP active layer, and a second cladding layer of p-type InGaAlP. An n-type GaAs current-blocking layer having a stripe opening and a p-type GaAs contact layer are sequentially formed on the second cladding layer by MOCVD crystal growth. A low-energy band gap region is defined in a central region of the active layer located immediately below the stripe opening. A high-energy band gap region is defined in a peripheral region of the active layer corresponding to a light output end portion of the laser and located immediately below the current-blocking layer. Therefore, self absorption of an oscillated laser beam at the output end portion can be reduced or prevented.

Abstract: A mobile receiver of the present invention which comprises memory means for storing therein receive frequency data and broadcasting station name data associated therewith with respect to respecitve areas, receivable/non-receivable decision means for determining broadcasting frequencies receivable at the current position, and means for comparing ones of the receive frequency data corresponding to one of the areas designated at operating means or ones of the receive frequency data corresponding to an automatically determined area with the receive frequency data stored in the memory means and for presenting one of the broadcasting station name data of the receive frequency at which the receiver is now receiving, whereby the user of the mobile receiver can advantageously know easily the name of one of broadcasting stations of the same broadcasting frequency located in different areas, to which the user is listening.

Abstract: In a semiconductor laser device, for emitting a laser beam having a wavelength .lambda., an n-type In.sub.0.5 (Ga.sub.1-x Al.sub.x)P first cladding layer is formed on an n-type GaAs substrate. An undoped InGaP active layer is formed on the first cladding layer and a p-type In.sub.0.5 (Ga.sub.1-x Al.sub.x).sub.0.5 P cladding layer is formed on the active layer. A p-type InGaP cap layer is formed on the second cladding layer and an n-type GaAs current restricting layer is formed on the second cladding layer. The aluminum composition ratio x of the cladding layer is 0.7. The active layer has a thickness of 0.06 .mu.m and the cladding layers have the same thickness H of 0.85 .mu.m. The active layer and the cladding layers have refractive indices n.sub.a and n.sub.c which satisfies the following inequalities:0.015.DELTA..sup.1/2 <d/.lambda.<0.028.DELTA..sup.-1/2and.DELTA.=(n.sub.a.sup.2 -n.sub.c.sup.2)/2n.sub.a.sup.2.

Abstract: A semiconductor laser device using double heterostructure comprised of In.sub.x Ga.sub.y Al.sub.1-x-y P (0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1), capable of preventing the leakage of the carriers and thereby reducing the threshold current, being operative with small threshold current density and at high temperature, and having a long lifetime. The device may include a double heterostructure formed on the GaAs substrate, comprised of In.sub.x Ga.sub.y Al.sub.1-x-y P (0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1) including an active layer, the active layer having an impurity concentration not greater than 5.times.10.sup.16 cm.sup.-3. The device may include a double heterostructure formed on the GaAs substrate, comprised of InGaP active layer and p-type In.sub.q (Ga.sub.1-z Al.sub.z).sub.q P (0.ltoreq.q.ltoreq.1, 0.ltoreq.z.ltoreq.1) cladding layer with a value of z between 0.65 and 0.75. The device may include a double heterostructure formed on the GaAs substrate, comprised of In.sub.x Ga.sub.y Al.sub.1-x-y P (0.

Abstract: An InGaAlP NAM structure laser is formed with a double-heterostructure section disposed on an n-type GaAs substrate. The double-heterostructure section includes a first cladding layer of n-type InGaAlP, a non-doped InGaP active layer, and a second cladding layer of p-type InGaAlP. An n-type GaAs current-blocking layer having a stripe opening and a p-type GaAs contact layer are sequentially formed on the second cladding layer by MOCVD crystal growth. A low-energy band gap region is defined in a central region of the active layer located immediately below the stripe opening. A high-energy band gap region is defined in a peripheral region of the active layer corresponding to a light output end portion of the laser and located immediately below the current-blocking layer. Therefore, self absorption of an oscillated laser beam at the output end portion can be reduced or prevented.

Abstract: In a semiconductor laser device, for emitting a laser beam having a wavelength .lambda., an n-type In.sub.0.5 (Ga.sub.1-x Al.sub.x)P first cladding layer is formed on an n-type GaAs substrate. An undoped InGaP active layer is formed on the first cladding layer and a p-type In.sub.0.5 (Ga.sub.1-x Al.sub.x).sub.0.5 P cladding layer is formed on the active layer. A p-type InGaP cap layer is formed on the second cladding layer and an n-type GaAs current restricting layer is formed on the second cladding layer. The aluminum composition ratio x of the cladding layer is 0.7. The active layer has a thickness of 0.06 .mu.m and the cladding layers have the same thickness H of 0.85 .mu.m. The active layer and the cladding layers have refractive indices n.sub.a and n.sub.c which satisfies the following inequalities:0.015.DELTA..sup.1/2 <d/.lambda.<0.028.DELTA..sup.-1/2and.DELTA.=(n.sub.a.sup.2 -n.sub.c.sup.2)/2n.sub.a.sup.