JP6849524B2 - Semiconductor laser light source - Google Patents

Description

The present invention relates to a semiconductor laser light source operating in a single mode used in medium and long distance optical fiber communication.

In medium- and long-distance optical communication systems, it is common to use wavelength division multiplexing (WDM) technology in order to increase the transmission capacity per optical fiber. At that time, since the light source is required to have a tunable characteristic that can output any wavelength channel, a tunable laser is used. In order to increase the transmission capacity, it is effective to pack the wavelength band occupied by the signal as closely as possible to improve the optical frequency utilization efficiency.

However, in order to improve the optical frequency utilization efficiency, it is necessary to improve the accuracy of the optical frequency (wavelength) of the light source. For example, in the case of a system for optical transmission of an NRZ (Non Return to Zero) signal having an optical frequency interval of 50 GHz and a signal speed of 10 Gbit / s, there is a margin in the occupied optical frequency band with respect to the optical frequency interval. Therefore, it is sufficient that the optical frequency accuracy of a commercially available light source is ± 2.5 GHz. However, in order to double the optical frequency utilization efficiency, if the optical frequency interval is halved to 25 GHz at a signal speed of 10 Gbit / s, the optical frequency accuracy of the light source needs to be increased to about ± 1 GHz.

Currently, tunable laser modules mainly used have a built-in wavelength rocker in order to stabilize the oscillation light frequency (wavelength). A wavelength rocker is an optical component composed of an etalon filter that serves as a wavelength reference, a photodiode (PD) for a monitor, and the like. By utilizing the optical frequency dependence of the transmittance of the etalon filter and controlling the oscillation optical frequency (wavelength) of the semiconductor laser to match the optical frequency of the etalon filter as a reference, the oscillation optical frequency (wavelength) of the semiconductor laser ( Wavelength) is stabilized.

Non-Patent Document 1 discloses an example of a type using a distributed feedback type laser array as a tunable laser. In this example, the laser module is composed of a light source block and a wavelength rocker block on which a tunable laser is mounted, and the temperature of each block is stabilized by a Peltier element. Specifically, the temperature of the laser chip is monitored by using a thermistor, and the temperature is controlled to be kept constant by using a Peltier element.

However, it is difficult to completely eliminate the temperature fluctuation of the laser chip because the monitor temperature by the thermistor and the temperature of the laser chip do not completely match and a slight measurement error occurs. In a general laser module, when the outside air temperature changes from 0 ° C. to 100 ° C. by about 100 ° C., the laser chip temperature changes by about ± 0.1 ° C. As a result, the refractive index of the semiconductor of the laser material changes, and the oscillation frequency changes by about ± 10 GHz. Therefore, it is not possible to obtain an accuracy of ± 1 GHz only by controlling the temperature of the laser.

Therefore, a wavelength rocker is used in a laser light source for wavelength division multiplexing (WDM) communication. As described above, the wavelength rocker is equipped with an etalon filter as a wavelength reference, and the optical frequency of the laser light source is stabilized by utilizing the optical frequency dependence of the transmittance of the etalon filter. As the material of the etalon filter, a material having a smaller temperature dependence of the refractive index than the semiconductor is used. For example, when quartz glass is used, the temperature dependence of the refractive index is 1/10 or less of that of the semiconductor material. Therefore, even if the temperature changes by about ± 0.1 degrees as described above, the refractive index fluctuation becomes 1/10, and the change in the reference light frequency (wavelength) can also be ± 1 GHz or less.

However, the conventional tunable laser disclosed in Non-Patent Document 1 has a problem that a time in which the accuracy of the optical frequency is not sufficient occurs immediately after the optical output is generated. This issue will be described in detail below. In order to operate the wavelength rocker, it is necessary that the laser beam is input. The optical frequency immediately after the transition from the state where there is no laser light output to the state where the laser light is output is not highly accurate, and then gradually by performing feedback control of the laser light frequency using the signal from the wavelength rocker. In addition, the accuracy of the optical frequency becomes high.

Since the accuracy of the optical frequency becomes high after a sufficient time has passed from the start of the output of the laser beam, the conventional tunable laser can be sufficiently used in a system in which the optical wavelength is not switched at all. However, in a system that can change the network configuration by switching the optical wavelength, if the accuracy of the optical frequency is not sufficient immediately after the optical output, it will affect other wavelength channels, which is large. It becomes an issue.

Ishii et al., "High-performance tunable light source technology", NTT Technology Journal, pp. 66-69, November 2007 issue

The present invention has been made in view of such a problem, and an object of the present invention is to realize a compact semiconductor laser light source having high optical frequency accuracy immediately after the generation of light output.

The semiconductor laser light source of the present invention includes a light source block including a semiconductor laser that oscillates in a single mode, a wavelength rocker block including an etalon filter into which the output light of the light source block is input, and an output of the wavelength rocker block. It includes an amplifier block that amplifies light and couples it to an optical fiber, and the amplifier block operates as an optical attenuator from the start of optical output of the semiconductor laser until a predetermined condition is satisfied, and the predetermined condition is satisfied. There saw including a semiconductor amplifier which operates as an amplifier when satisfied, the wavelength locker block includes a first photodetector for detecting said etalon filter, the intensity of the input to the wavelength locker block light, It includes a second receiver that is input to the wavelength rocker block and detects the intensity of light that has passed through the etalon filter, and further includes a first thermoelectric element provided in the light source block and the first. A first temperature control unit that controls the temperature of the light source block through the first thermoelectric element so that the optical frequency of the semiconductor laser becomes a desired value based on an electric signal obtained from the second receiver. It is determined that the predetermined condition is satisfied when the semiconductor amplifier is operated as an optical attenuator at the start of the optical output of the semiconductor laser and the electric signal indicating that the optical frequency of the semiconductor laser is stable is obtained. The semiconductor amplifier control unit that operates the semiconductor amplifier as an amplifier, the second thermoelectric element provided in the wavelength rocker block, the third thermoelectric element provided in the amplifier block, and the wavelength rocker. The temperature measured by the first temperature sensor provided on the block, the second temperature sensor provided on the amplifier block, and the first temperature sensor matches the desired wavelength rocker temperature set value. So that the temperature measured by the second temperature control unit that controls the temperature of the wavelength rocker block through the second thermoelectric element and the second temperature sensor matches the desired amplifier temperature set value. It is characterized by including a third temperature control unit that controls the temperature of the amplifier block through the third thermoelectric element.

Further, the semiconductor laser light source of the present invention includes a light source block including a semiconductor laser oscillating in a single mode, a wavelength rocker block including an etalon filter into which the output light of the light source block is input, and the wavelength rocker block. The amplifier block comprises an amplifier block that amplifies the output light of the semiconductor laser and couples the output light to the optical fiber, and the amplifier block operates as an optical attenuator from the start of optical output of the semiconductor laser until a predetermined condition is satisfied. The wavelength rocker block includes the semiconductor amplifier that operates as an amplifier when the conditions of the above conditions are satisfied, and the wavelength rocker block includes the etalon filter and a first receiver that detects the intensity of light input to the wavelength rocker block. A second thermoelectric element provided in the light source block and a first thermoelectric element provided in the light source block, including a second receiver which is input to the wavelength rocker block and detects the intensity of light transmitted through the etalon filter. With the first temperature control unit that controls the temperature of the light source block through the first thermoelectric element so that the optical frequency of the semiconductor laser becomes a desired value based on the electric signal obtained from the second receiver. The semiconductor amplifier is operated as an optical attenuator from the start of optical output of the semiconductor laser until a specified time elapses, and when the specified time elapses, it is determined that the predetermined condition is satisfied, and the semiconductor amplifier is determined. A semiconductor amplifier control unit that operates as an amplifier, a second thermoelectric element provided in the wavelength rocker block, a third thermoelectric element provided in the amplifier block, and a wavelength rocker block. The second temperature sensor, the second temperature sensor provided in the amplifier block, and the second temperature sensor so that the temperature measured by the first temperature sensor matches the desired wavelength rocker temperature setting value. The third thermoelectric unit so that the temperature measured by the second temperature control unit that controls the temperature of the wavelength rocker block through the thermoelectric element and the second temperature sensor matches the desired amplifier temperature set value. It is characterized by including a third temperature control unit that controls the temperature of the amplifier block through an element.

Further , in one configuration example of the semiconductor laser light source of the present invention, the semiconductor laser is a distributed feedback type laser or a distributed reflection type laser having a wavelength selection function by a diffraction grating.

Further, in one configuration example of the semiconductor laser light source of the present invention, the light source block includes a distributed feedback type laser array, an N to 1 optical combiner that combines the N light outputs of the distributed feedback type laser array, and an N to 1 optical combiner. A semiconductor laser that oscillates in a single mode is provided by the distributed feedback type laser array, the N: 1 optical combiner, and the semiconductor amplifier, including a semiconductor amplifier that amplifies the laser light output from the N: 1 optical combiner. It is characterized by being configured.
Further, in one configuration example of the semiconductor laser light source of the present invention, the light source block includes a distributed reflection type laser array, an N to 1 optical combiner that combines the N light outputs of the distributed reflection type laser array, and an N to 1 optical combiner. A semiconductor laser that oscillates in a single mode is provided by the distributed reflection type laser array, the N: 1 optical combiner, and the semiconductor amplifier, which includes a semiconductor amplifier that amplifies the laser light output from the N: 1 optical combiner. It is characterized by being configured.

According to the present invention, an amplifier block that amplifies the output light of the wavelength rocker block and couples it to an optical fiber is provided, and the amplifier block is light-attenuated from the start of light output of the semiconductor laser until a predetermined condition is satisfied. By providing a semiconductor amplifier that operates as a device and operates as an amplifier when a predetermined condition is satisfied, the semiconductor amplifier in the amplifier block acts as an optical attenuator even when light output is generated from the light source block. Thereby, the optical output to the optical fiber can be turned off. In this state, since the light of the light source block is input to the wavelength rocker block, the light frequency can be stabilized. If the semiconductor amplifier of the amplifier block is operated as the original amplifier after the optical frequency becomes sufficiently stable, light with high optical frequency accuracy can be output. As a result, in the present invention, it is possible to realize a compact semiconductor laser light source having high optical frequency accuracy immediately after the generation of optical output.

FIG. 1 is a block diagram showing a schematic configuration of a semiconductor laser light source according to an embodiment of the present invention. FIG. 2 is a block diagram showing a schematic configuration of a conventional semiconductor laser light source. FIG. 3 is a diagram showing the optical frequency dependence of the monitor output current ratio in the embodiment of the present invention. FIG. 4 is a diagram showing the time variation of the light output and the light frequency of the conventional semiconductor laser light source. FIG. 5 is a diagram showing the time variation of the light output and the light frequency of the semiconductor laser light source in the embodiment of the present invention.

Hereinafter, examples of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a semiconductor laser light source according to an embodiment of the present invention. In FIG. 1, the locus of the laser beam is shown by a dotted line. In the semiconductor laser light source according to this embodiment, three functional blocks of a light source block 200, a wavelength rocker block 300, and an amplifier block 400 are arranged in a package 101. Each functional block is mounted on the Peltier elements 201, 301, 401, and the temperature can be adjusted independently.

In the light source block 200, a semiconductor laser chip 203 having a tunable function, a lens 204 for converting light emitted from the semiconductor laser chip 203 into a parallel beam, and a semiconductor laser chip 203 on a metal carrier made of CuW or the like. A thermistor 202 for monitoring the temperature of the

The wavelength rocker block 300 is provided with an optical isolator 308 for blocking the return light to the semiconductor laser chip 203, a partial reflection mirror 303 for reflecting a part of the laser light on the carrier, and light. A partial reflection mirror 304, an etalon filter 307, a photodiode 305 for intensity monitoring, a photodiode 306 for wavelength monitoring, and a thermista 302 for temperature monitoring are mounted. Has been done.

The light transmitted through the wavelength rocker block 300 is coupled to the semiconductor amplifier 403 by the lens 404 on the amplifier block 400. The output light of the semiconductor amplifier 403 is converted into a parallel beam by the lens 405.
The light that has passed through the amplifier block 400 passes through the transparent window 102, is collected by the lens 103, and is optically coupled to the optical fiber 105. The end of the optical fiber 105 is fixed by a fiber ferrule 104. The package 101 is airtightly sealed in order to improve the reliability of the semiconductor laser.

Parts such as the semiconductor laser chip 203, photodiodes (receivers) 305, 306, Peltier elements (thermoelectric elements) 201, 301, 401, and thermistors (temperature sensors) 202, 302, 402 are all terminals provided in the package 101. The semiconductor laser light source can be operated by the external temperature control units 500 to 502, the laser driver 503, and the semiconductor amplifier control unit 504.

In this embodiment, a distributed feedback type (DFB: Distributed FeedBack) laser array is used as the semiconductor laser. In the semiconductor laser chip 203, a distributed feedback laser array 205 including N distributed feedback lasers having different oscillation wavelengths and an N to 1 light output of the distributed feedback laser array 205 are combined. The optical combiner 206 and the semiconductor amplifier 207 that amplifies the laser beam output from the N: 1 optical combiner 206 are integrated.

The light source block 200 selectively oscillates one of the distributed feedback laser arrays 205 in the semiconductor laser chip 203 by the external laser driver 503, and further, the external temperature control unit 500 causes the Peltier block 200 to oscillate the distributed feedback laser. By controlling the element 201 to change the temperature of the distributed feedback type laser array 205, the oscillation wavelength can be changed in a wide range.

In this embodiment, the distributed feedback type laser array 205 is used, but the distributed reflection type (DBR: Distributed Bragg Reflector) in which the diffraction grating for selecting the wavelength is provided in a portion different from the semiconductor gain region is used. ) A laser array may be used.
Further, instead of the distributed feedback type laser array 205, a single distributed feedback type laser having a wavelength selection function by a diffraction grating or a single distributed reflection type laser may be used.

For comparison, FIG. 2 shows the configuration of a conventional semiconductor laser light source. It can be seen that the conventional semiconductor laser light source is composed of only the light source block 200 and the wavelength rocker block 300.

Hereinafter, an actual operation example of this embodiment will be described with reference to FIG. The light output from the semiconductor laser chip 203 is converted into a parallel beam by the lens 204 and proceeds to the wavelength rocker block 300. A part of the laser beam introduced into the wavelength rocker block 300 is guided to the intensity monitoring photodiode 305 and the wavelength monitoring photodiode 306 by the partial reflection mirrors 303 and 304. Each of the intensity monitoring photodiode 305 and the wavelength monitoring photodiode 306 converts the intensity of the incident light into a current value.

An etalon filter 307 is inserted in the optical path from the partial reflection mirror 304 to the wavelength monitor photodiode 306. Since the transmittance of the etalon filter 307 changes according to the change in the wavelength (optical frequency) of the light incident on the etalon filter 307, the transmittance is incident on the photodiode 306 for wavelength monitoring according to the change in the wavelength of the light. The intensity of light also changes. Therefore, the value of the current output from the wavelength monitor photodiode 306 also changes according to the wavelength (optical frequency) of the light incident on the etalon filter 307.

FIG. 3 shows the characteristics of PD1 / PD2, which is the value obtained by dividing the output current PD1 of the wavelength monitoring photodiode 306 by the output current PD2 of the intensity monitoring photodiode 305 when the optical frequency is actually changed. Since this characteristic is standardized by the output current PD2 of the intensity monitoring photodiode 305, it is equivalent to the characteristic of the etalon filter 307. In this embodiment, when the frequency of the light incident on the etalon filter 307 is 193100 GHz by controlling the Peltier element 301 by the external temperature control unit 501 to adjust the temperature of the wavelength rocker block 300 to an appropriate value. The slope of the transmission characteristic of the etalon filter 307 is set to a negative maximum value. The value of the monitor current ratio PD1 / PD2 at this time is 1.26.

Therefore, the external temperature control unit 500 controls the Peltier element 201 so as to keep the monitor current ratio PD1 / PD2 at 1.26 to adjust the temperature of the distributed feedback type laser array 205, thereby causing the distributed feedback type. The oscillation light frequency of the laser array 205 is controlled. In this way, the frequency of the light output from the wavelength rocker block 300 can be accurately maintained at 193100 GHz.

The transmission characteristics of the etalon filter 307 change periodically, and the period depends on the optical distance between the two mirrors of the etalon filter 307. In this embodiment, as is clear from FIG. 3, the etalon filter 307 designed and manufactured so that the period of the transmission characteristic is 50 GHz was used. Therefore, the laser wavelength can be stabilized to the optical frequencies arranged at intervals of 50 GHz. Further, since the transmitted light frequency of the etalon filter 307 can be changed depending on the temperature, it is possible to stabilize the transmitted light frequency to an arbitrary light wavelength by controlling the temperature of the wavelength rocker block 300 using the Peltier element 301. Is.
The above-mentioned operation of the wavelength rocker is a well-known operation performed from a conventional semiconductor laser light source.

Next, the characteristic configuration of this embodiment will be described. In this embodiment, an amplifier block 400 is provided after the wavelength rocker block 300, and a semiconductor amplifier 403 (SOA: Semiconductor Optical Amplifier) mounted on the amplifier block 400 enables control of light amplification and absorption. The point is that it is different from the conventional one. The effect of this amplifier block 400 will be described below.

FIG. 4 is a diagram showing a time transition of an optical output and an oscillating optical frequency in a conventional semiconductor laser light source. In this example, at time 0, the control to the semiconductor laser light source is started so as to have an arbitrary optical frequency. Specifically, control parameters such as a chip temperature and a laser current for setting an arbitrary optical frequency are recorded in advance in a semiconductor storage device. At time 0, the temperature control unit controls the temperature of the light source block 200 by using the Perche element 201 so that the temperature measured by the thermistor 202 matches the initial setting value of the chip temperature recorded in the semiconductor storage device. , The temperature of the wavelength rocker block 300 is controlled by using the Perche element 301 so that the temperature measured by the thermistor 302 matches the wavelength rocker temperature set value recorded in the semiconductor storage device.

When the temperature of the laser measured by the thermistor 202 approaches a desired temperature, the laser driver supplies the laser current of the value recorded in the semiconductor storage device to the distributed feedback laser array 205 to generate an optical output. Let me.

In the example of FIG. 4, the light output is generated when 4 seconds have passed from the time 0. At this time, since the laser temperature is slightly different from the desired temperature (the above-mentioned initial setting value), the frequency of the light output from the semiconductor laser light source deviates from the desired optical frequency by about several GHz. After the light output from the distributed feedback laser array 205 is generated, the temperature control unit sets the light source block so that the light frequency becomes a desired value based on the electric signals (PD1, PD2) from the wavelength rocker block 300. Control the temperature of 200. In the example of FIG. 4, it can be seen that the frequency of the light output from the semiconductor laser light source falls within ± 1 GHz with respect to the desired value ft when the time 0 to 6 seconds has elapsed.

FIG. 5 is a diagram showing the time transition of the light output and the oscillation light frequency in the semiconductor laser light source of this embodiment. Similar to the case of FIG. 4, at time 0, the control to the semiconductor laser light source is started so as to have an arbitrary optical frequency. Specifically, the initial setting value of the chip temperature (light source block temperature) for setting an arbitrary optical frequency, the wavelength rocker temperature setting value, the amplifier temperature setting value, the laser current setting value, the monitor current setting value, and the amplifier operation. Control parameters such as current set values are pre-recorded in a semiconductor storage device (not shown).

At time 0, the temperature control unit 500 controls the temperature of the light source block 200 by using the Peltier element 201 so that the temperature measured by the thermistor 202 matches the initial setting value of the chip temperature recorded in the semiconductor storage device. .. Further, at time 0, the temperature control unit 501 uses the Perche element 301 to match the temperature measured by the thermistor 302 with the wavelength rocker temperature set value recorded in the semiconductor storage device, and the temperature of the wavelength rocker block 300. The temperature control unit 502 controls the temperature of the amplifier block 400 by using the Perche element 401 so that the temperature measured by the thermistor 402 matches the amplifier temperature set value recorded in the semiconductor storage device. ..

Further, in this embodiment, at the same time as such temperature control, the light source block 200 is operated to generate a laser beam output. Specifically, at time 0, the laser driver 503 supplies the laser current of the set value recorded in the semiconductor storage device to the distributed feedback type laser corresponding to the desired optical frequency, and emits light from the light source block 200. Produce output. Therefore, it is possible to immediately control the optical frequency stabilization using the wavelength rocker. That is, the temperature control unit 500 makes the ratio PD1 / PD2 of the monitor current obtained from the wavelength rocker block 300 match the monitor current set value (1.26 in the above example) recorded in the semiconductor storage device. The temperature of the light source block 200 is controlled by using the Peltier element 201.

The semiconductor amplifier control unit 504 can control the gain of the semiconductor amplifier 403 by adjusting the current supplied to the semiconductor amplifier 403. Specifically, when a current is passed through the semiconductor amplifier 403 in the amplifier block 400, the light is amplified and output, but when the p-side electrode and the n-side electrode of the semiconductor amplifier 403 are short-circuited, the semiconductor amplifier 403 emits light. Is absorbed, so it acts as a light attenuator and no light is output.

Therefore, the semiconductor amplifier control unit 504 short-circuits the p-side electrode and the n-side electrode of the semiconductor amplifier 403 from time 0 (at the time when the optical output of the semiconductor laser starts) until a predetermined condition is satisfied. Operate the 403 as an optical attenuator. Therefore, the optical output from the amplifier block 400 to the optical fiber 105 is almost zero.

Subsequently, the semiconductor amplifier control unit 504 determines the distribution feedback type laser array 205 when the monitor current ratio PD1 / PD2 falls within a desired range (within a certain range centered on 1.26 in the above example). It is determined that the optical frequency of the semiconductor amplifier is stable, the predetermined condition is satisfied, and the current of the amplifier operating current set value recorded in the semiconductor storage device is supplied to the semiconductor amplifier 403 to amplify the semiconductor amplifier 403. Operate as. As a result, light is output from the amplifier block 400 to the optical fiber 105. In this way, by switching the operation of the amplifier block 400 from the attenuation operation to the amplification operation, it is possible to increase the accuracy of the optical frequency (optical wavelength) immediately after the optical output of the amplifier block 400 is generated.

In the example of FIG. 5, light output is generated from the semiconductor laser light source when 4 seconds have passed from time 0, and immediately after this generation, the light frequency is already within ± 1 GHz with respect to the desired value ft. You can see that.
As described above, in the semiconductor laser light source of the present embodiment, it is possible to control to output light only when the optical frequency is stable by utilizing the amplification / attenuation switching of the amplifier block 400. A small, variable wavelength light source with high optical frequency accuracy can be obtained.

The semiconductor amplifier control unit 504 may determine that the predetermined condition is satisfied when the specified time t has elapsed from the time 0. As the specified time t, a time at which the frequency of the light output from the distributed feedback type laser array 205 is expected to be sufficiently stable may be set in advance.

The present invention can generally be used in optical communication systems. In particular, it can be used as a transmitter / receiver for an optical communication system.

101 ... Package, 102 ... Transparent window, 103, 204, 404, 405 ... Lens, 104 ... Fiber ferrule, 105 ... Optical fiber, 200 ... Light source block, 201, 301, 401 ... Perche element, 202, 302, 402 ... Thermistor, 203 ... Semiconductor laser chip, 205 ... Distributed feedback laser array, 206 ... N to 1 optical combiner, 207 ... Semiconductor amplifier, 300 ... Wavelength rocker block, 303, 304 ... Partial reflection mirror, 305 ... For intensity monitor Photodiode, 306 ... Photodiode for wavelength monitoring, 307 ... Etalon filter, 308 ... Optical isolator, 400 ... Amplifier block, 403 ... Semiconductor amplifier, 500-502 ... Temperature control unit, 503 ... Laser driver, 504 ... Semiconductor amplifier Control unit.

Claims (5)

A light source block containing a semiconductor laser that oscillates in a single mode,
A wavelength rocker block containing an etalon filter to which the output light of this light source block is input,
It is equipped with an amplifier block that amplifies the output light of this wavelength rocker block and couples it to an optical fiber.
The amplifier block, the works from the light output start time of the semiconductor laser as a light attenuator until a predetermined condition is satisfied, saw including a semiconductor amplifier in which the predetermined condition is operated as an amplifier when satisfied,
The wavelength rocker block transmitted the etalon filter, the first receiver for detecting the intensity of light input to the wavelength rocker block, and the etalon filter input to the wavelength rocker block. Including a second receiver that detects the intensity of light
Further, a first thermoelectric element provided in the light source block and
A first temperature that controls the temperature of the light source block through the first thermoelectric element so that the optical frequency of the semiconductor laser becomes a desired value based on the electric signals obtained from the first and second receivers. Control unit and
When the semiconductor amplifier is operated as an optical attenuator at the start of the optical output of the semiconductor laser and the electric signal indicating that the optical frequency of the semiconductor laser is stable is obtained, it is determined that the predetermined condition is satisfied. The semiconductor amplifier control unit that operates the semiconductor amplifier as an amplifier,
A second thermoelectric element provided in the wavelength rocker block,
A third thermoelectric element provided in the amplifier block,
The first temperature sensor provided in the wavelength rocker block and
A second temperature sensor provided in the amplifier block and
A second temperature control unit that controls the temperature of the wavelength rocker block through the second thermoelectric element so that the temperature measured by the first temperature sensor matches the desired wavelength rocker temperature set value.
It is provided with a third temperature control unit that controls the temperature of the amplifier block through the third thermoelectric element so that the temperature measured by the second temperature sensor matches a desired amplifier temperature set value. A characteristic semiconductor laser light source. A light source block containing a semiconductor laser that oscillates in a single mode,
A wavelength rocker block containing an etalon filter to which the output light of this light source block is input,
It is equipped with an amplifier block that amplifies the output light of this wavelength rocker block and couples it to an optical fiber.
The amplifier block includes a semiconductor amplifier that operates as an optical attenuator from the start of optical output of the semiconductor laser until a predetermined condition is satisfied, and operates as an amplifier when the predetermined condition is satisfied.
The wavelength rocker block transmitted the etalon filter, the first receiver for detecting the intensity of light input to the wavelength rocker block, and the etalon filter input to the wavelength rocker block. Including a second receiver that detects the intensity of light
Further, a first thermoelectric element provided in the light source block and
A first temperature that controls the temperature of the light source block through the first thermoelectric element so that the optical frequency of the semiconductor laser becomes a desired value based on the electric signals obtained from the first and second receivers. Control unit and
The semiconductor amplifier is operated as an optical attenuator from the start of optical output of the semiconductor laser until a specified time elapses, and when the specified time elapses, it is determined that the predetermined condition is satisfied, and the semiconductor amplifier is used. A semiconductor amplifier control unit that operates as an amplifier,
A second thermoelectric element provided in the wavelength rocker block,
A third thermoelectric element provided in the amplifier block,
The first temperature sensor provided in the wavelength rocker block and
A second temperature sensor provided in the amplifier block and
A second temperature control unit that controls the temperature of the wavelength rocker block through the second thermoelectric element so that the temperature measured by the first temperature sensor matches the desired wavelength rocker temperature set value.
It is provided with a third temperature control unit that controls the temperature of the amplifier block through the third thermoelectric element so that the temperature measured by the second temperature sensor matches a desired amplifier temperature set value. A characteristic semiconductor laser light source. In the semiconductor laser light source according to claim 1 or 2.
The semiconductor laser is a distributed feedback type laser or a distributed reflection type laser having a wavelength selection function by a diffraction grating, and is a semiconductor laser light source. In the semiconductor laser light source according to claim 1 or 2.
The light source block is
Distribution feedback laser array and
An N-to-1 optical combiner that combines the N optical outputs of this distributed feedback laser array,
Including a semiconductor amplifier that amplifies the laser light output from this N-to-1 optical combiner,
A semiconductor laser light source characterized in that a semiconductor laser oscillating in a single mode is configured by these distributed feedback type laser arrays, an N to 1 optical combiner, and a semiconductor amplifier. In the semiconductor laser light source according to claim 1 or 2.
The light source block is
Distributed reflection laser array and
An N-to-1 optical combiner that combines the N light outputs of this distributed reflection laser array,
Including a semiconductor amplifier that amplifies the laser light output from this N-to-1 optical combiner,
A semiconductor laser light source characterized in that a semiconductor laser oscillating in a single mode is configured by these distributed reflection type laser arrays, an N: 1 optical combiner, and a semiconductor amplifier.

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