Abstract: An optical module according to the present invention includes: a light-emitting device that outputs laser light; a temperature adjustment unit that adjusts a wavelength of the laser light outputted from the light-emitting device so as to be locked at a predetermined wavelength; a wavelength monitor unit that receives laser light outputted from the light-emitting device by allowing the laser light to pass through an optical filter provided above the temperature adjustment unit and monitors the wavelength thereof; a package for sealing the light-emitting device, the temperature adjustment unit, and the wavelength monitor unit into the inside thereof; and a package temperature detection unit for detecting a temperature of the package, in which the temperature adjustment unit adjusts an oscillation wavelength of the laser light outputted from the light-emitting device to the predetermined lock wavelength based on a signal outputted from the wavelength monitor unit, and a signal from the package temperature detect

Abstract: On a second thermo-module there are disposed a prism, an optical filter, and a sub-mount, via a base respectively. On the front side of the sub-mount, there are disposed a first photodetector and a second photodetector. The optical filter is structured with a crystal member that satisfies a condition that ?+(1/n0)×(?n/?T) becomes not more than 3.5, where ? is a coefficient of linear expansion, n0 is a refractive index at a normal temperature, and ?n is a change of a refractive index corresponding to a temperature variation ?T.

Abstract: An optical module of the present invention can stabilize e.g. the temperature of a wavelength monitor portion so that the oscillating wavelength of a laser diode is stabilized. The laser diode and the wavelength monitor portion for monitoring the wavelength of the laser diode are included in a package, and are mounted onto a thermo module. The wavelength monitor portion comprise at least an optical filter positioned to receive and filter at least a component of the laser beam and a light receiving device to receive the filtered light through the optical filter and monitor a wavelength of the laser beam. A heat shield member for reducing heat transmission from the package to the wavelength monitor portion is arranged in at least one portion of a peripheral area of the wavelength monitor portion.

Abstract: A transmitting device includes a light-emitting device for outputting a laser beam, a temperature regulator for regulating the temperature in the light-emitting device, a wavelength monitor device for receiving the laser beam from the light-emitting device after it has passed through a optical filter thermally coupled with the light-emitting device, a control unit for controlling the temperature in the temperature regulator based on the signal outputted from the wavelength monitor device such that the lasing wavelength in the laser beam outputted from the light-emitting device will be locked at a predetermined locked wavelength, a temperature-sensing unit for sensing the temperature in the optical filter, and a correcting unit for outputting a correction signal toward the control unit based on the temperature sensed by the temperature-sensing unit, the correction signal being operative to command the correction of any deviation in the locked wavelength associated with the temperature characteristic in the opt

Abstract: An optical module includes a light-emitting device that outputs laser light, a temperature detection unit that is arranged in proximity to the light-emitting device and detects the temperature of the light-emitting device, a wavelength monitor unit that receives laser light outputted from the light-emitting device and having passed through an optical filter and monitors the wavelength of the laser light, and a temperature adjustment unit that adjusts the wavelength of laser light outputted from the light-emitting device based on a signal outputted from the wavelength monitor unit. The temperature adjustment unit adjusts the wavelength of the laser light so as to fall within a wavelength range, in which the wavelength is adjustable by the wavelength monitor unit, based on a signal from the temperature detection unit, and then adjusts the wavelength of the laser light so as to be locked at a predetermined wavelength based on the signal from the wavelength monitor unit.

Abstract: In an external cavity laser, which comprises an FBG section having the Bragg wavelength of light reflected by a grating adjusted to a given wavelength and a laser light emitting device designed to generate light, optically coupled to the FBG section to ensure input and output of the light, and including a high-reflection surface for reflecting the generated light, the light is resonated by a cavity formed between the high-reflection surface and the grating, whereby a laser beam having a given oscillation wavelength is oscillated through a connector. The FBG section is located on an optical path between the laser light emitting device and the connector, and an isolator is located on an optical path between the FBG section and the connector. The isolator serves to absorb and intercept reflected waves or reflected return light from the connector.

Abstract: An optical filter is provided on a first thermo-module whose temperature is controlled to be constant, via a base. Accordingly, a wavelength discrimination characteristic of the optical filter and an optical isolator can be stabilized, thereby realizing more accurate wavelength locking. Further, a second thermo-module is provided on the first thermo-module whose temperature is controlled to be constant. Accordingly, the temperature control range of the second thermo-module can be expanded, and hence the wavelength variable range of a semiconductor laser device provided on the second thermo-module via a base and a submount can be expanded.

Abstract: The present invention provides a system for controlling a wavelength of laser light comprising: a light-emitting device for outputting laser light; means for regulating a temperature of said light-emitting device; a wavelength monitor for receiving the laser light transmitted from said light-emitting device through an optical filter, said optical filter having a periodic wavelength-transmissivity intensity curve; a controlling unit for providing a control signal to control an current supplied to said temperature regulating means responsive to a output signal from said wavelength monitor; said control signal having a polarity; and means for switching the polarity of said control signal.

Abstract: A wavelength monitor capable of obtaining an optical detection signal of high quality is proposed. In the wavelength monitor, a light incident surface of an optical filter is disposed with an inclination relative to the light incident direction. With this arrangement, it is possible to make the route of a reflection light that has been reflected from the light incident surface of the optical filter deviate large from the route of an incident light that has been incident to the optical filter. Consequently, the reflected light is prevented from being incident to a semiconductor laser device or optical detectors.

Abstract: An optical module has a hermetically sealed package, a semiconductor laser element located within the package for outputting a laser beam, an optical fiber for receiving and externally delivering the laser beam outputted from the front end face of the semiconductor laser element, a prism for receiving a monitoring laser beam outputted from the back end face of the semiconductor laser element and for dividing the received laser beam into two laser beam components which are inclined relative to the optical axis with predetermined angles less than 90 degrees, a first photodiode for receiving one of the laser beam components divided by the prism, a second photodiode for receiving the other laser beam component from the prism, an optical filter disposed between the first photodiode and the prism and adapted to permit only a laser beam having a predetermined wavelength range to pass therethrough, and a PD carrier in which the first and second photodiodes are mounted on the same mount surface.

Abstract: A semiconductor laser apparatus comprises a light-emitting portion including a light-emitting device for outputting a laser beam, a light-receiving element for receiving the laser beam outputted from said light-emitting device, a wavelength monitoring portion including an optical system disposed between said light-emitting device and said light-receiving element, a control portion for controlling the wavelength of the laser beam outputted from said light-emitting device by controlling the temperature of said light-emitting device based on the wavelength of the laser beam detected by said wavelength monitoring portion, an optical isolator disposed on the optical path between said light-emitting device and said wavelength monitoring portion for preventing the light from returning from said wavelength monitoring portion back to said light-emitting device, and a temperature regulating portion for independently controlling the temperatures of said light-emitting portion and wavelength monitoring portion.

Abstract: An optical module according to the present invention includes: a light-emitting device that outputs laser light; a temperature adjustment unit that adjusts a wavelength of the laser light outputted from the light-emitting device so as to be locked at a predetermined wavelength; a wavelength monitor unit that receives laser light outputted from the light-emitting device by allowing the laser light to pass through an optical filter provided above the temperature adjustment unit and monitors the wavelength thereof; a package for sealing the light-emitting device, the temperature adjustment unit, and the wavelength monitor unit into the inside thereof; and a package temperature detection unit for detecting a temperature of the package, in which the temperature adjustment unit adjusts an oscillation wavelength of the laser light outputted from the light-emitting device to the predetermined lock wavelength based on a signal outputted from the wavelength monitor unit, and a signal from the package temperature detect

Abstract: An optical module of the present invention can stabilize e.g. the temperature of a wavelength monitor portion so that the oscillating wavelength of a laser diode is stabilized. The laser diode and the wavelength monitor portion for monitoring the wavelength of the laser diode are included in a package, and are mounted onto a thermo module. The wavelength monitor portion comprise at least an optical filter positioned to receive and filter at least a component of the laser beam and a light receiving device to receive the filtered light through the optical filter and monitor a wavelength of the laser beam. A heat shield member for reducing heat transmission from the package to the wavelength monitor portion is arranged in at least one portion of a peripheral area of the wavelength monitor portion.

Abstract: On a second thermo-module there are disposed a prism, an optical filter, and a sub-mount, via a base respectively. On the front side of the sub-mount, there are disposed a first photodetector and a second photodetector. The optical filter is structured with a crystal member that satisfies a condition that &agr;+(1/n0)×(&Dgr;n/&Dgr;T) becomes not more than 3.5, where &agr; is a coefficient of linear expansion, n0 is a refractive index at a normal temperature, and &Dgr;n is a change of a refractive index corresponding to a temperature variation &Dgr;T.

Abstract: A transmitting device includes a light-emitting device for outputting a laser beam, a temperature regulator for regulating the temperature in the light-emitting device, a wavelength monitor device for receiving the laser beam from the light-emitting device after it has passed through a optical filter thermally coupled with the light-emitting device, a control unit for controlling the temperature in the temperature regulator based on the signal outputted from the wavelength monitor device such that the lasing wavelength in the laser beam outputted from the light-emitting device will be locked at a predetermined locked wavelength, a temperature-sensing unit for sensing the temperature in the optical filter, and a correcting unit for outputting a correction signal toward the control unit based on the temperature sensed by the temperature-sensing unit, the correction signal being operative to command the correction of any deviation in the locked wavelength associated with the temperature characteristic in the opt

Abstract: An optical filter is provided on a first thermo-module whose temperature is controlled to be constant, via a base. Accordingly, a wavelength discrimination characteristic of the optical filter and an optical isolator can be stabilized, thereby realizing more accurate wavelength locking. Further, a second thermo-module is provided on the first thermo-module whose temperature is controlled to be constant. Accordingly, the temperature control range of the second thermo-module can be expanded, and hence the wavelength variable range of a semiconductor laser device provided on the second thermo-module via a base and a submount can be expanded.

Abstract: The present invention provides an optical module having a light-emitting device for outputting a laser beam, a first temperature sensor disposed in proximity to the light-emitting device for sensing the temperature in the light-emitting device, a first temperature adjustment unit for adjusting the temperature in the light-emitting device, a wavelength monitor for receiving and monitoring the laser beam from the light-emitting device after passed through an optical filter, a second temperature sensor disposed in the wavelength monitor for sensing the temperature in the wavelength monitor, a second temperature adjustment unit for adjusting the temperature in the wavelength monitor, and a third temperature sensor disposed directly in or in proximity to the optical filter for sensing the temperature in the optical filter.

Abstract: First and second temperature control modules are disposed on a bottom surface inside a package. The first module has a prism, a wavelength filter, and a mount that holds a photodiode disposed thereon, thereby to form a wavelength monitoring section. The second module has an isolator, a lens holder that holds a lens, a laser mount on which a laser device is fixed, and a lens holder that holds a lens disposed thereon, thereby to form a laser emitter. An insulating plate is disposed between the first and second modules so as to prevent the occurrence of interference between the first and second modules.

Abstract: An optical module includes a light-emitting device that outputs laser light, a temperature detection unit that is arranged in proximity to the light-emitting device and detects the temperature of the light-emitting device, a wavelength monitor unit that receives laser light outputted from the light-emitting device and having passed through an optical filter and monitors the wavelength of the laser light, and a temperature adjustment unit that adjusts the wavelength of laser light outputted from the light-emitting device based on a signal outputted from the wavelength monitor unit. The temperature adjustment unit adjusts the wavelength of the laser light so as to fall within a wavelength range, in which the wavelength is adjustable by the wavelength monitor unit, based on a signal from the temperature detection unit, and then adjusts the wavelength of the laser light so as to be locked at a predetermined wavelength based on the signal from the wavelength monitor unit.

Abstract: A wavelength monitor capable of obtaining an optical detection signal of high quality is proposed. In the wavelength monitor, a light incident surface of an optical filter is disposed with an inclination relative to the light incident direction. With this arrangement, it is possible to make the route of a reflection light that has been reflected from the light incident surface of the optical filter deviate large from the route of an incident light that has been incident to the optical filter. Consequently, the reflected light is prevented from being incident to a semiconductor laser device or optical detectors.