Abstract: Conventionally, in the wavelength locking optical system, the wavelength as detected is deviated from a targeted range owing to the change of the peripheral temperature resulting from the temperature characteristics of the wavelength error detection device. To solve this prior issue, it is arranged such that a portion of the wavelength error detection device, through which portion light-beams passes, contacts a material of high heat conductivity.

Abstract: The present invention is to reduce the package cost and secure the high reliability in an optical module having an optical device and an optical fiber.

Abstract: A conventional problem is to provide an optical module capable of being reflow mounted together with electronic components collectively, and, at the same time, securing a mechanical strength that can bear a large stress at the time of an attachment/detachment of the optical fiber. A solution to the above-mentioned problem can be attained by using an optical connector removable type optical module for reflow mounting having a fixing structure for fixing itself to a mount board, including a receptacle part installed to an optical module 19 to which an optical connector 1 is detachably connected; electric terminals 4 for reflow mounting that are arranged corresponding to lands 8 on a mount board 6; and stud parts 5 that are able to fit in fixing holes 7 on the mount board 6.

Abstract: An optical module for an optical device and an optical fiber is constituted by a pre-molded plastic package. In forming the plastic package, the main flowing direction of the molding resin is substantially parallel with the optical axis of the optical fiber. The optical module is formed by molding the resin by an injection method using pressure and then solidifying the resin. When the plastic package is formed by comprehensive molding, the flowing direction of the resin is parallel with the optical axis direction of the optical fiber to be installed in the optical module. As a result, for comprehensive molding, the molding pressure applied to the optical fiber is reduced. By using the resin case that is formed, the resulting package exhibits high rigidity and low thermal expansion properties in connection with the flowing direction of the resin, thus reducing the external stress and thermal stress applied to the optical fiber.

Abstract: To resolve a problem in which in an optical output and wavelength monitor integrated type semiconductor laser module monolithically integrated in parallel with a plurality of semiconductor lasers, since light emitting positions of the respective semiconductor lasers differ, an allowable range of an optical incident position of the monitor is exceeded, the optical incident position of the monitor is confined in the allowable range by integrating backward optical waveguides for guiding backward beam of the respective semiconductor lasers to a narrow range at a backward end of a semiconductor chip along with the semiconductor lasers, whereby there can be easily realized a semiconductor laser module with a built-in optical monitor even in the case of the chip integrated with the plurality of semiconductor lasers and can be realized an inexpensive optical module having high function.

Abstract: An object of disclosed technology is to control lasing wavelengths so that a wavelength shift does not occurs. Another object is to permit wavelengths of a light source for wavelength division multiplexing optical-fiber communication system to be variable in response to an ITU-TS grid. A means for achieving the objects is as follows: locating an etalon in a light path of diode laser light, which is a parallel plane wave changed by a collimator lens; generating a wavelength error signal from a difference between both of divided pieces of light from transmitted light or reflected light; and locking a wavelength of a diode laser device according to the wavelength error signal.

Abstract: In a module for optical communication comprising an optical fiber including an axial-end surface, and an optical element including an optical surface facing to the axial-end surface in such a manner that a light is transmitted between the optical surface and the axial-end surface,

Abstract: An optical transmission module or an optical module has a receptacle attached adjacent to an optical component module or package, and a plug configured to connect vertically with the receptacle from above the module. The outer peripheral shape of the housing is designed to fit within an area of the receptacle that faces upwardly to receive the plug in an insertion direction extending vertically downwardly. In the housing of the plug, a ferrule is attached to an end of an optical fiber and a sleeve covers the optical fiber and the ferrule. A knob is used for moving the optical fiber, the sleeve and the ferrule in the lightwave propagation direction, which is transverse to the plug insertion direction.

Abstract: A module for optical communication includes an optical fiber having an axial-end surface and an optical element having an optical surface facing the axial-end surface in such a manner that light is transmitted between the optical surface and the axial-end surface. The optical surface defines a first plane that is not perpendicular to the longitudinal axis of the optical fiber. A synthetic resin is provided between the optical surface of the optical element and the axial-end surface of the optical fiber so that light is transmitted through the synthetic resin.

Abstract: An optical transmission module or an optical module has a receptacle attached adjacent to an optical component module or package, and a plug configured to connect vertically with the receptacle from above the module. The outer peripheral shape of the housing is designed to fit within an area of the receptacle that faces upwardly to receive the plug in an insertion direction extending vertically downwardly. In the housing of the plug, a ferrule is attached to an end of an optical fiber and a sleeve covers the optical fiber and the ferrule. A knob is used for moving the optical fiber, the sleeve and the ferrule in the lightwave propagation direction, which is transverse to the plug insertion direction. Before connecting the plug, the knob is retracted to pull the ferrule and the sleeve within the plug housing.

Abstract: An optical transmission module or an optical module has a receptacle attached adjacent to an optical component module or package, and a plug configured to connect vertically with the receptacle from above the module. The outer peripheral shape of the housing is designed to fit within an area of the receptacle that faces upwardly to receive the plug in an insertion direction extending vertically downwardly. In the housing of the plug, a ferrule is attached to an end of an optical fiber and a sleeve covers the optical fiber and the ferrule. A knob is used for moving the optical fiber, the sleeve and the ferrule in the lightwave propagation direction, which is transverse to the plug insertion direction. Before connecting the plug, the knob is retracted to pull the ferrule and the sleeve within the plug housing.

Abstract: An optical module for an optical device and an optical fiber is constituted by a pre-molded plastic package. In forming the plastic package, the main flowing direction of the molding resin is substantially parallel with the optical axis of the optical fiber. The optical module is formed by molding the resin by an injection method using pressure and then solidifying the resin. When the plastic package is formed by comprehensive molding, the flowing direction of the resin is parallel with the optical axis direction of the optical fiber to be installed in the optical module. As a result, for comprehensive molding, the molding pressure applied to the optical fiber is reduced. By using the resin case that is formed, the resulting package exhibits high rigidity and low thermal expansion properties in connection with the flowing direction of the resin, thus reducing the external stress and thermal stress applied to the optical fiber.

Abstract: The present invention is to reduce the package cost and secure the high reliability in an optical module having an optical device and an optical fiber.

Abstract: An optical module for an optical device and an optical fiber is constituted by a pre-molded plastic package. In forming the plastic package, the main flowing direction of the molding resin is substantially parallel with the optical axis of the optical fiber. The optical module is formed by molding the resin by an injection method using pressure and then solidifying the resin. When the plastic package is formed by comprehensive molding, the flowing direction of the resin is parallel with the optical axis direction of the optical fiber to be installed in the optical module. As a result, for comprehensive molding, the molding pressure applied to the optical fiber is reduced. By using the resin case that is formed, the resulting package exhibits high rigidity and low thermal expansion properties in connection with the flowing direction of the resin, thus reducing the external stress and thermal stress applied to the optical fiber.

Abstract: There is disclosed a harmonic modulation device of waveguide type including a semiconductor laser, a waveguide for generating a nonlinear optical harmonic of the semiconductor laser by keeping phase matching, means for leading an optical beam of the semiconductor laser to the waveguide, electrodes disposed on the waveguide, and means for modulating a refractive index of the waveguide electro-optically to modulate a phase matching condition and thereby modulate an intensity of the harmonic.

Abstract: An optical information reproducing method, for optically reproducing information recorded on a recording medium, irradiates the recording medium with a laser beam and detects the light returning from the recording medium. When the diffracted light returning from the recording medium is detected, the optical intensity distribution of the diffracted light is detected by a plurality of detectors to produce a plurality of signals, and the signals are calculated to produce a reproduced signal for detecting the information.

Abstract: An optical fiber is held in a ferrule, and then the ferrule is located in a positioning groove formed in a substrate, thereby aligning the optical fiber with an optical device bonded to a surface of the substrate. Then, a lid is placed on the substrate in such a manner that the ferrule is located in a positioning groove formed in the lid and that the optical device is received in a cavity formed in the lid. The ferrule is thus held between the two grooves, and in this condition a resin is filled in the two grooves, thereby retaining the ferrule. Then, the lid is sealingly secured to the substrate. After these parts are thus assembled together, this assembly is put in dies, and then a package is molded.

Abstract: An optical head apparatus for recording and reproducing data to and from optical disks, the apparatus boosting recording density by use of an objective lens with a higher numerical aperture (NA) than ever. A phase plate is added to the pupil position of the objective lens or to a position close thereto. The phase plate arrangement provides a deeper focal length, reduces the adverse effects of aberration and eliminates the need for a tilt servo mechanism despite the use of the objective lens having a greater numerical aperture than before.

Abstract: An information recording medium includes an information recording layer on which at least information is to be recorded by irradiating light, and a light transmission restricting layer which has a plurality of nonlinear transmission characteristics or nonlinear reflection characteristics for the intensity of the light irradiated and which has an optical material for restricting the transmission or reflection of the light according to the respective characteristics when the light is irradiated onto the information recording layer. An information recording and reproducing unit uses the information recording medium and includes an information recording position setting unit for deciding a position at which information is to be recorded on the information recording medium by detecting a direction of an easy magnetization axis.

Abstract: A short-wavelength laser having a stable output and an optical information processing system capable of high-density recording are disclosed. A solid-state laser is used as a light source, and a nonlinear optical crystal is arranged in a resonator in order to produce a short wavelength by means of a solid-state laser. The retardation of the nonlinear optical crystal is controlled by determining the length of the nonlinear optical crystal. A solid-state laser device having a stable output with the noise removed from a pumping power light source is also provided. Further, the solid-state laser device is used as a light source for the optical information processing system, and the light of irrelevant wavelengths contained in the light from the solid-state laser device are removed by a device having the ability to select wavelengths. Thus, not only a stable light source with a short wavelength but also an optical information processing system capable of high-density recording are realized.