Hitachi, Ltd.

Ricoh Company, Ltd.

Other

Hitachi Koki Co., Ltd.

Hitachi Computer Peripherals Co., Ltd.

Ricoh Printing Systems Co., Ltd.

Shinichi Nakatsuka

Takashi Kajimura

Susumu Saito

Yuichi Ono

Akira Arimoto

Naoki Chinone

Kazuhisa Uomi

Junshin Sakamoto

Motoyasu Terao

Takeshi Shimano

Shinya Kobayashi

Keizo Suzuki

Tetsuo Ono

Hiroshi Masuda

Tadashi Fukuzawa

Tsukuru Ohtoshi

Toshimasa Kamisada

Kenji Uchida

Seiji Maruo

Toshihiro Kawano

Kunio Sato

Misuzu Sagawa

Katsuhiko Mitani

Mitsuhiro Mori

Junji Shigeta

Yasutoshi Kashiwada

Masahide Tokuda

Satoru Kikuchi

Hidekazu Okuhira

Susumu Hiraoka

Takuma Tanimoto

Kazuo Sakaki

Kazuhiro Soga

Hitoshi Ishii

Yoshiaki Ogino

Jyunshin Sakamoto

Hiroshi Inenaga

Tsukuru Ootoshi

According to an aspect of the present invention, there is provided a method for assembling a semiconductor laser device, including: preparing a laser chip including: a substrate; stripe waveguides that are formed on the substrate and that each includes a gain producing area and a window area; electrodes formed on the stripe waveguides; an insulating layer formed on the electrodes; a metal layer formed on the insulating layer; projections arranged at an interval in the window areas; and joining structures connected to the electrodes and formed in the window areas; preparing a submount including: a first solder; second solders arranged at the interval; and submount electrodes connected to the second solders; contacting the laser chip to the submount by fitting the projections with respect to the second solders; and heating the submount and the laser chip.

Method for assembling array-type semiconductor laser device

According to an aspect of the present invention, there is provided a semiconductor laser apparatus including: a laser device including: a semiconductor substrate, first and second resonators formed on the semiconductor substrate, and first and second electrodes that are respectively connected with the first and the second resonators and extend away from each other; and a submount including: third and fourth electrodes respectively adhered with the first and the second electrodes; wherein each of the first and the second electrodes includes: an energizing portion covering the corresponding resonator, an adhering portion being disposed separately from the energizing portion and having a height larger than that of the energizing portion, and a stress-absorbing portion formed in the adhering portion.

Semiconductor laser apparatus and method for mounting semiconductor laser apparatus

In a semiconductor laser diode array, first electrodes of a laser chip are coated with an insulating substance, and contact holes are formed in the insulating substance. The laser chip is assembled by being secured on a submount while facing downward, wherein electrodes and a solder pattern are provided in the submount in a direction crossing resonators.

Semiconductor laser diode array

To achieve stable, high capacity, high speed recording. Of two light beams emitted from a light irradiation means, one or two beams are made pass through an optical path changeable member whereof at least one of the thickness and refractive index changes continuously or in two or more steps immediately after emission from the light irradiation means, so that a difference is introduced into the optical path length of the two beams, and the focusing point of one beam is made to vary to coincide with a position in the recording layer used for playback or recording. Another light beam is used for servo. Converging of light during recording or read of a multilayer recording medium is performed with higher precision than in the prior art, so higher density, higher capacity recording/playback can be performed.

Information recording apparatus, information recording medium and information recording medium

When a semiconductor laser is energized, a virtual junction temperature rises to reduce a threshold current, which fluctuates a light output by the unit of a several microseconds, thereby causing printing irregularity. An object of the invention is to prevent the fluctuation in light output occurring due to the temperature change caused by the energization of the semiconductor laser with a simple circuit structure and under the driving condition of a small bias current. A constant voltage driving is performed with a circuit or device having negative resistance characteristics being arranged in series with the semiconductor laser. Thus, the reduction in light output of the semiconductor laser due to the temperature rise is compensated for by an increase in driving current thanks to a reduction in rising voltage of current/voltage characteristics.

Driving system for a semiconductor laser device

The subject of the disclosed art is to prevent a short circuit between plural electrodes caused by soldering in the assembling process for a semiconductor laser element. The constitution for improving the subject is as follows. A semiconductor laser device comprises a semiconductor laser chip having a first electrode and a laser sustaining material, in which the laser sustaining material has electrodes and solder layers connected electrically therewith on the surface where the semiconductor laser chip is mounted, the first electrode of the semiconductor laser chip is connected with the solder layer of the laser sustaining material and at least the solder layer of the laser sustaining material extends from at least one end face in the longitudinal direction of an optical resonator of the semiconductor laser chip to the outside of the optical resonator.

Semiconductor laser array

An electric photograph system for improving non-linearities of an exposing light intensity and an operating current at a low exposing level when performing analog printing operation. A range (saturable absorber) having a saturable absorbing characteristic is provided in a part of an optical path including a semiconductor laser as light source to improve the non-linearity of the operating current when the light intensity is weak. The saturable absorber may be made in the form of a non current injected area provided in a part of the semiconductor laser as the light source or a thin film layer provided partly in films coated on a facet of the semiconductor laser. Due to the provision of the saturable absorber, the light output power characteristic can exhibit its linearity in its low optical power range, the size of a printing dot can be arithmetically changed, and thus fine laser printing can be realized.

Electric photograph system

A laser printer is provided printing with a high precision simply and at a high speed, and the laser printer uses a semiconductor laser which can vary the diameter of the emitted light while the light density is held constant. In the laser printer, laser rays emitted from a semiconductor laser are irradiated onto a photoconductor to vary its surface potential to produce a charge pattern particles adhere, and printing is performed by transferring the changed particles to a printing object. The semiconductor laser has a plurality of waveguide type resonators, the emitted beams of the resonators having a spatial superposition, and light emission is possible so that the emitted beams of the resonators having a spatial superposition with respect to each other among the resonators of the semiconductor laser are not substantially superimposed in time.

Laser printer and light source suitable for the same

A light beam scanning apparatus in which laser power and spot shape of an emitted laser beam are controlled, has a laser control signal generating part for changing a picture signal to a laser power control signal and a spot shape control signal, a laser power control current generating part which is driven by the laser power control signal, a spot shape control current generating part which is driven by the shape control signal, and a laser beam emission part for emitting a laser beam having a laser power and a spot shape which are controlled by the control signals via a commonly used light wave guiding part, wherein the control signal generating part generates or corrects the control signals based on at least one of the difference between the laser power of a beam to be emitted and a detected laser power, the difference between the spot shape of a beam to be emitted and a detected laser power, a detected temperature at the laser beam emission part, and an effective light emission pixel number.

Light beam scanning apparatus which controls power and spot shape of

A semiconductor laser device is provided which is designed to prevent end surface optical damage, thereby permitting an increase in the output of the semiconductor laser. To achieve this, an active layer at the light emitting end surface portion of the semiconductor laser device is recessed inwardly by a distance between 50 nm and 300 nm (depending on the amount of etching) from the end surfaces of the crystal layers lying on both sides of the active layer. The recess serves to improve the heat dissipation of the active layer portion. This results in improving the amount of light output of the semiconductor laser which is possible without causing optical damage. A method for making the device is also provided. This method permits achieving the above-noted advantages simply by adding an etching step to the conventional semiconductor laser fabrication process, without requiring special equipment or technique.

Semiconductor laser device and a method for the manufacture thereof

A method may be used to dry etch a sample including a plurality of regions different from each other in the photo-absorption of a light having a specified wavelength using an etching gas plasma. The method is capable of selectively etching the desired material from a plurality of materials having different types of band gap energies or from a plurality of materials having different band gap energies. The method includes a step of irradiating a light having the specified wavelength on the sample for reducing an etching rate of a region having a large photo-absorption coefficient to the light, thereby selectively etching a region having a small photo-absorption coefficient to the light.

Dry etching method

A semiconductor laser having a stripe-like lasing region, wherein the structure of the lasing region such as the mechanism of optical guiding of the lateral mode control structure is made different between the central portion in the lasing region and portions close to facets, in order to reduce optical feedback induced noise and astigmatism, and to facilitate the manufacture thereof.

Semiconductor laser

In a semiconductor laser device having an active layer and clad layers, lens-like portions which magnify radiation are formed in the active layer and/or a clad layer where the radiation leaks, thereby making it possible to enlarge a stripe width and to produce a fundamental mode oscillation of high output. Futher, a lens-like portion which condenses the radiation is formed at an end face of an emission port for a laser beam, thereby making it possible to narrow a radiant angle of the laser beam.

Semiconductor laser device having a lens-like refractive index

A stripe groove is formed on a semiconductor substrate and buried by lamination of multiple semiconductor layers, and a channel being lower than the substrate surface is formed outside the groove near at least one mirror edge, such that a laser diode with decreased astigmatism can be produced.

Laser diode

A p-GaAlAs cladding layer is exposed to the air if a groove of the form of a stripe is formed by chemical etching in an n-GaAs layer that serves as a current confinement layer on the p-GaAlAs cladding layer, the groove being so formed as to reach the cladding layer. The GaAlAs is oxidized so easily that an unstable degradation layer is formed on the surface thereof. To solve this problem according to the prior art, an undoped GaAs layer that serves as a cover layer is formed on the p-GaAlAs cladding layer, the n-GaAs layer is formed, and the etching is effected so that the undoped GaAs layer is simply exposed. The undoped GaAs layer is then heated in the MBE apparatus while being irradiated with the As molecular beam and is thermally etched. Therefore, the cladding layer is exposed in vacuum and the p-GaAlAs layer is formed thereon. However, this method is not suited for mass-production since the thermal etching is unstable and it needs the MBE apparatus of a very high degree of vacuum. Quality of the crystal decreases, too, due to the heating. This invention therefore provides a fabrication process of semiconductor lasers in which the cover layer disappears due to interdiffusion of constituent elements that stem from the diffusion of impurities such as zinc ions in the undoped GaAs layer.

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Hino, Japan

Shinichi Nakatsuka