Ricoh Company, Ltd.

Kazuhiro Harasaka

Shunichi Sato

Naoto Jikutani

Satoru Sugawara

Akihiro Itoh

Toshihiro Ishii

Kazuhiko Adachi

Yoshihiro Ohba

Hiroyoshi Shouji

Masahiro Hayashi

Katsunari Hanaoka

Kazuma Izumiya

Yasuhiro Higashi

Toshihide Sasaki

Kengo Makita

Ryoichiro Suzuki

Shinji Satoh

A surface emitting laser includes a first reflecting mirror; a second reflecting mirror; an active region between the first reflecting mirror and the second reflecting mirror. The first reflecting mirror and the second reflecting mirror each include a plurality of low refractive-index layers having a first refractive index; and a plurality of high refractive-index layers having a second refractive index higher than the first refractive index. The plurality of low refractive-index layers and the plurality of high refractive-index layers are alternated one after another. The plurality of high refractive-index layers of the first reflecting mirror includes a first layer; and a second layer having a higher thermal diffusion property in an in-plane direction than the first layer.

Surface emitting laser, surface emitting laser device, light source device, and detection apparatus

A disclosed surface-emitting laser module includes a surface-emitting laser formed on a substrate to emit light perpendicular to its surface, a package including a recess portion in which the substrate having the surface-emitting laser is arranged, and a transparent substrate arranged to cover the recess portion of the package and the substrate having the surface-emitting laser such that the transparent substrate and the package are connected on a light emitting side of the surface-emitting laser. In the surface-emitting laser module, a high reflectance region and a low reflectance region are formed within a region enclosed by an electrode on an upper part of a mesa of the surface-emitting laser, and the transparent substrate is slanted to the surface of the substrate having the surface-emitting laser in a polarization direction of the light emitted from the surface-emitting laser determined by the high reflectance region and the low reflectance region.

Surface-emitting laser module, optical scanner device, and image forming apparatus

An alkali metal cell is disclosed, including a substrate in which is formed an opening which penetrates from one face to the other face thereof; a first transparent substrate bonded to the other face of the substrate; and a second transparent substrate bonded to the one face of the substrate, wherein an alkali metal is sealed into a space surrounded by the first transparent substrate and the second transparent substrate in the opening of the substrate, wherein, in the substrate and the second transparent substrate, the space is enclosed by a bonding between a first bonding metal layer formed by a first bonding metal and a second bonding metal layer formed by a second bonding metal, and wherein the second bonding metal layer has a bonding temperature higher than that of the first bonding metal layer.

Alkali metal cell, atomic oscillator, and alkali metal cell fabricating method

A surface-emitting laser device includes a transparent dielectric layer provided in an emitting region and configured to cause a reflectance at a peripheral part to be different from a reflectance at a central part in the emitting region. In the surface-emitting laser device, the thickness of a contact layer is different between a region having a relatively high reflectance and a region having a relatively low reflectance in the emitting region. The contact layer is provided on the high refractive index layer of an upper multilayer film reflecting mirror, and the total optical thickness of the high refractive index layer and the contact layer in the region having the relatively low reflectance is deviated from an odd number multiple of a one quarter oscillation wavelength of laser light emitted from the emitting region.

Surface-emitting laser device, surface-emitting laser array, optical scanner, image forming apparatus, and method for manufacturing surface-emitting laser device

A heater substrate for heating an alkali metal cell including an alkali metal includes a first heater wiring formed in a region surrounding an alkali metal encapsulating part in which the alkali metal is encapsulated; a second heater wiring formed in the region surrounding the alkali metal encapsulating part and inside the first heater wiring; and a third heater wiring formed outside the first heater wiring. A first electric current flowing in the first heater wiring is divided into a second electric current flowing in the second heater wiring and a third electric current flowing in the third heater wiring. A direction of the first electric current is opposite to a direction of the second electric current and a direction of the third electric current.

Heater substrate, alkali metal cell unit and atomic oscillator

A surface emitting laser array includes a light emitting unit having a lower reflection mirror, a resonator structure including an active layer, and an upper reflection mirror laminated on a substrate; an electrode for the light emitting unit; a wiring member that establishes electrical connection between the light emitting unit and the electrode; and the substrate on which more than one of the light emitting units, the electrodes, and the wiring members are arranged. The light emitting unit has anisotropic internal stress, and the distance between the center of a first light emitting unit and the center line of the corresponding wiring member is arranged to be different from the distance between the center of a second light emitting unit and the center line of the corresponding wiring member so that variations in the polarization directions of the light emitting units may be within a predetermined range.

Surface emitting laser array and image forming apparatus

A surface-emitting laser device configured to emit laser light in a direction perpendicular to a substrate includes a p-side electrode surrounding an emitting area on an emitting surface to emit the laser light; and a transparent dielectric film formed on an outside area outside a center part of the emitting area and within the emitting area to lower a reflectance to be less than that of the center part. The outside area within the emitting area has shape anisotropy in two mutually perpendicular directions.

Surface-emitting laser device, surface-emitting laser array, optical scanning apparatus and image forming apparatus

A method of manufacturing a surface-emitting laser element having a light-emitting mesa structure with an emitting area including a high-reflectance portion and a low-reflectance portion includes forming a layered body that includes a lower reflecting mirror, a cavity structure, and an upper reflecting mirror on a substrate; forming a first area on an upper surface of the layered body; forming a second area having the same size as the first area on the upper surface of the layered body; forming a light-emitting mesa structure and a monitoring-mesa structure by etching the first area and the second area, respectively; forming a confinement structure including a current passage area surrounded by an oxide in the light-emitting mesa structure and the monitoring-mesa structure; and measuring the size of the current passage area of the monitoring-mesa structure.

Surface-emitting laser element, surface-emitting laser array, optical scanning apparatus, image forming apparatus, and method of manufacturing surface-emitting laser element

A disclosed surface-emitting laser element includes a resonator structure having an active layer, a first semiconductor multilayer mirror and a second semiconductor multilayer mirror configured to sandwich the resonator structure having the active layer, an electrode provided around an emission region of a light-emitting surface, and a dielectric film provided in a peripheral portion within the emission region and outside a central portion of the emission region to make a reflectance of the peripheral portion lower than a reflectance of the central portion. In the surface-emitting laser element, an outer shape of a portion where the electrode provided around the emission region of the light-emitting surface is in contact with a contact layer includes corners.

Surface-emitting laser element, surface-emitting laser array, optical scanner device, and image forming apparatus

A disclosed method of manufacturing a surface emitting laser includes laminating a transparent dielectric layer on an upper surface of a laminated body; forming a first resist pattern on an upper surface of the dielectric layer, the first resist pattern including a pattern defining an outer perimeter of a mesa structure and a pattern protecting a region corresponding to one of the relatively high reflection rate part and the relatively low reflection rate part included in an emitting region; etching the dielectric layer by using the first resist pattern as an etching mask; and forming a second resist pattern protecting a region corresponding to an entire emitting region. These steps are performed before the mesa structure is formed.

Method of manufacturing surface emitting laser, and surface emitting laser, surface emitting laser array, optical scanning device and image forming apparatus

A surface emitting laser diode comprises a substrate, a lower reflector formed over the substrate, an active layer formed over the lower reflector, an upper reflector formed over the active layer, a current restrict structure including a current confinement region surrounded by insulation region. The current restrict structure is disposed in an upper reflector or between an active layer and the upper reflector, and an upper electrode formed over the upper reflector includes an aperture which corresponds to an emission region from which light is emitted in a first direction perpendicular to a surface of a substrate. The emission region and the current restrict structure including the current confinement region are selectively configured to obtain high single transverse mode, stabilized polarization direction, isotropic beam cross section and small divergence angle, while allowing the device to be manufactured with high yield rate.

Surface emitting laser diode, optical scanning apparatus and image forming apparatus

A disclosed surface-emitting laser element includes an emission region configured to emit a laser beam and a high reflectance region including a first dielectric film having a first refractive index and a second dielectric film having a second refractive index differing from the first refractive index where the first dielectric film and the second dielectric film are stacked within the emission region to provide high reflectance. In the surface-emitting laser element, the high reflectance region is formed in a region including a central portion of the emission region and is configured to include shape anisotropy in two orthogonal directions in a plane in parallel with the emission region.

Growing community of inventors

Miyagi, Japan

Kazuhiro Harasaka