Mitsubishi Denki Kabushiki Kaisha

Kenji Ikeda

Yutaka Nagai

Yutaka Mihashi

Kimio Shigihara

Nobuaki Kaneno

Tetsuo Shiba

Kazuhisa Takahashi

Hideyo Higuchi

Yoichiro Ota

A semiconductor laser device having a pair of cavity facets provided confronting to each other and conducting a laser oscillation at wavelength .lambda., includes a reflection film having a reflectivity R.sub.1 against a laser light of wavelength .lambda. provided on one of cavity facets among the pair of cavity facets, and partial reflection films having a reflectivity R.sub.2 higher than the reflectivity R.sub.1 against laser light of wavelength .lambda., provided at a plurality of portions of the laser oscillation regions in parallel with each other on the reflection film. Therefore, a semiconductor laser device in which the active layer emits light uniformly without arising filamentation is obtained.

Semiconductor laser device

A semiconductor laser device having a relative wide active region and a distributed Bragg reflector facet wherein a relative high reflectance region one third of the active region width is centrally disposed on a surface of the laser through which light is emitted.

A semiconductor laser device provided with a broad light waveguide through which a higher order transverse oscillation modes can propagate, includes at least one of laser facet having a high reflectance region having a width of about 1/5 to 1/2 of the width of the light waveguide located at a central portion thereof and a low reflectance region having a lower reflectance than the high reflectance region located at both sides of the high reflectance region whereby higher order modes of oscillation can be suppressed.

A semiconductor laser device for a laser printer in which a reflection film having reflectance in a range of 45 to 65% is provided on a laser output facet for outputting a laser output beam.

Semiconductor laser including a reflection film

A semiconductor laser device includes semiconductor layers including a semiconductor layer having a stripe groove having a reverse trapezoidal cross section and a bent active layer spaced from and in the configuration of the groove wherein the bottom width of the groove is less than 2 microns and the distance from the active layer to the bottom of the groove is more than 0.6 micron.

A semiconductor laser array includes a pair of regions of an active layer for emitting laser lights being provided so as to produce a predetermined angle therebetween; the respective regions of the active layer being provided so as to have TE wave electric field vectors of different directions from each other in a plane vertical to the emitting direction of the output laser light. As such, laser light emitted from each of the active layer regions can be used independently without interference from the other.

Semiconductor laser array with independently usable laser light emission

A semiconductor laser device which includes a semiconductor substrate; a semiconductor active layer; a semiconductor waveguiding layer provided adjacent to the active layer having a larger energy band gap than that of the active layer; a first and a second semiconductor cladding layer provided such that the semiconductor waveguiding layer and the active layer are positioned between by the two cladding layers, which cladding layers have larger energy band gaps than that of the waveguiding layer; and a periodic refractive index distribution being provided in a direction parallel with the active layer inside a waveguide produced by the refractive index differences produced at the above-mentioned four layers.

A semiconductor laser device which includes a first conductivity type semiconductor substrate; a first conductivity type first cladding layer, an active layer, and a second conductivity type second cladding layer successively provided on the substrate, wherein both the cladding layers have energy band gaps larger than that of the active layer; a first conductivity type current blocking layer having an energy band gap larger than that of the second cladding layer being provided on the second cladding layer, having a groove removed therefrom so as to form an exposed stripe portion on the second cladding layer; and a second conductivity type third cladding layer having an energy band gap smaller than that of the current blocking layer and larger than that of the active layer formed on the current blocking layer and on the stripe portion.

A semiconductor light receiving device, including; a photo diode having a polyimide film as a surface protection film, and a hermetically sealed package including the photo diode in an ambient gas including oxygen.

Growing community of inventors

Itami, Japan

Kenji Ikeda