JP2002246690A - Semiconductor laser device, method of manufacturing the same, and semiconductor laser module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor laser device and semiconductor laser module which can produce a minimum driving power and a maximum light power conversion efficiency when a semiconductor laser device for producing a desired light output is implemented. SOLUTION: A constant resonator length of 1,000 μm. or more as a parameter is determined so that a driving power corresponding to a desired light output is in the vicinity of a minimum on the basis of a relationship of the driving power to the light output of 50 mW or more. For example, when the light output is 360 mW, a resonator length of 1,500 μm is selected and determined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor laser device having a structure in which structures for achieving a desired optical output and a high optical power exchange efficiency are appropriately combined, a method for manufacturing the same, and a semiconductor laser module.

[0002]

2. Description of the Related Art In recent years, with the spread of various multimedia such as the Internet, there is an increasing demand for large capacity optical communication. Conventionally, in optical communication,
1310 which is a wavelength at which light absorption by an optical fiber is small.
Transmission using a single wavelength in the band of 1 nm or 1550 nm was common. In this scheme,
In order to transmit a large amount of information, it is necessary to increase the number of optical fibers laid in the transmission path, and there is a problem that the cost increases as the transmission capacity increases.

Therefore, wavelength division multiplexing (WDM: Waveleng)
th Division Multiplexing) communication system has come to be used. This WDM communication system mainly uses an erbium-doped fiber amplifier (EDFA).
In this method, transmission is performed using a plurality of wavelengths in the 1550 nm band, which is the operating band. In this DWDM communication system or WDM communication system, optical signals of a plurality of different wavelengths are simultaneously transmitted using one optical fiber, so that it is not necessary to lay new lines, and the transmission capacity of the network is dramatically increased. It is possible to bring increase.

A high-output semiconductor laser module for excitation is used for exciting the EDFA. In particular, 1480n
The semiconductor laser module for pumping in the m band has 1) high reliability, 2) high conversion efficiency of the erbium-doped fiber, and is advantageous for increasing the output of the amplifier, 3) wide absorption band of the erbium-doped fiber and multi-wavelength And 4) peripheral optical components such as an isolator, a wavelength combiner, and a polarization combiner are provided. Thus, by using a plurality of pumping semiconductor laser modules by wavelength combining, polarization combining, and the like, a pumping light source of a high-output optical amplifier is realized and used in an optical amplification system.

[0005]

Generally, when a current is injected into a semiconductor laser device (semiconductor laser device), the optical output increases, but the decrease in the optical output due to heat generation of the semiconductor laser device itself occurs at the same time. This occurs and saturates at a constant drive current, and the light output does not increase even if the drive current is increased thereafter.

Therefore, in order to increase the drive current value at which saturation occurs, the length of the resonator of the semiconductor laser device is increased to obtain a desired optical output. Conversely, in order to reduce the drive current required to obtain a desired optical output, an appropriate resonator length is selected, and a semiconductor laser device having the selected resonator length has been manufactured. FIG. 19 is a diagram showing the relationship between the optical output and the drive current, using the resonator length of the semiconductor laser device as a parameter. For example, when realizing a semiconductor laser device having an optical output of 360 mW, referring to FIG. 19, a cavity length of 1300 μm at which the drive current is minimized
Was decided.

However, if the length of the resonator of the semiconductor laser device is increased, the shape of the semiconductor laser device is physically different. Therefore, when determining the resonator length of the semiconductor laser device only from the viewpoint of the drive current, the In addition to the power consumed by the optical output of the semiconductor laser device, the reactive power due to series resistance and thermal resistance consumed by other components of the semiconductor laser device itself also increases, and the optical power conversion efficiency decreases. There is a problem that occurs. Here, the optical power conversion efficiency is a value obtained by dividing the optical output of the semiconductor laser device by the driving power of the semiconductor laser device.

Further, when the reactive power consumed by the semiconductor laser device, that is, the difference between the driving power and the optical output increases,
Since this difference is mainly converted into heat, there is a problem that the structure for heat dissipation becomes large and the semiconductor laser module on which the semiconductor laser device is mounted becomes large.

Further, in order to minimize the driving power or maximize the optical power conversion efficiency, besides optimizing the resonator length, for example, parameters such as the carrier concentration of Zn as an impurity in the upper cladding layer are changed. Optimization is also conceivable.

[0010] The present invention has been made in view of the above,
It is an object of the present invention to provide a semiconductor laser device in which driving power is minimized or optical power conversion efficiency is maximized when realizing a semiconductor laser device capable of obtaining a desired optical output, a manufacturing method thereof, and a semiconductor laser module. .

[0011]

In order to achieve the above object, a semiconductor laser device according to a first aspect of the present invention has a cavity length of a semiconductor laser device and an upper clad of the semiconductor laser device, wherein a constant optical output is used as a parameter. The driving power is determined based on the relationship between each element of the semiconductor laser device including the carrier concentration of the layer and the driving power or the optical power conversion efficiency of the semiconductor laser device, and the driving power is close to the minimum corresponding to a desired optical output. Alternatively, each element value of the semiconductor laser device in which the light power conversion efficiency is close to the maximum is provided.

According to the first aspect of the present invention, each element of the semiconductor laser device including the cavity length of the semiconductor laser device and the carrier concentration of the upper cladding layer of the semiconductor laser device, using a constant optical output as a parameter. And the drive power or optical power conversion efficiency of the semiconductor laser device is determined based on the relationship between the drive power and the optical power conversion efficiency corresponding to a desired optical output. By realizing a semiconductor laser device having each element value of the laser device, a desired optical output of 50 mW or more can be obtained when the driving power is near the minimum or the optical power conversion efficiency is near the maximum.

According to a second aspect of the present invention, there is provided a semiconductor laser device which is determined based on a relationship between a driving power and an optical output of 50 mW or more with a constant resonator length of 1000 μm or more as a parameter, and which corresponds to a desired optical output. And a resonator length of 1000 μm or more at which the driving power to be driven is close to the minimum.

According to the invention of claim 2, 1000 μm
Based on the relationship of the drive power to the optical output of 50 mW or more with the constant resonator length of m or more as a parameter, the resonator length at which the drive power corresponding to the desired optical output is near the minimum is determined. By realizing a semiconductor laser device having a cavity length of 1000 μm or more, a desired optical output of 50 mW or more can be obtained at a driving power near the minimum.

Further, according to a third aspect of the present invention, there is provided a semiconductor laser device having a constant light output of 50 mW or more as a parameter.
The optical power conversion efficiency is determined based on the relationship of the optical power conversion efficiency with respect to the cavity length of 000 μm or more, and the optical power conversion efficiency corresponding to the desired optical output has a resonator length near the maximum value.

According to the third aspect of the present invention, based on the relationship between the optical power conversion efficiency and the cavity length of 1000 μm or more, with the constant optical output of 50 mW or more as a parameter, the light corresponding to the desired optical output is obtained. The resonator length at which the power conversion efficiency is close to the maximum value is determined. By realizing a semiconductor laser device having the determined resonator length of 1000 μm or more, a desired optical power conversion efficiency of 50 mW or more can be achieved. Light output can be obtained.

According to a fourth aspect of the present invention, in the semiconductor laser device according to the above invention, the cavity length is determined based on an approximate expression that maximizes optical power conversion efficiency corresponding to the desired optical output. It is characterized by being performed.

According to the fourth aspect of the present invention, when the length of the resonator is determined, the length is determined based on an approximate expression that maximizes the optical power conversion efficiency corresponding to the desired optical output. I have.

According to a fifth aspect of the present invention, in the above-described semiconductor laser device, the driving power is determined based on a relationship between a driving power and a cavity length of 1000 μm or more, with a constant optical output of 50 mW or more as a parameter. It is characterized by having a resonator length of 1000 μm or more at which the driving power for a desired optical output is near the minimum.

According to the fifth aspect of the present invention, the driving power for a desired optical output is determined based on the relationship between the driving power and the resonator length of 1000 μm or more, using a constant optical output of 50 mW or more as a parameter. Is the minimum neighborhood 1
By realizing a semiconductor laser device having a cavity length of 000 μm or more, a desired optical output of 50 mW or more can be obtained with low driving power.

According to a sixth aspect of the present invention, in the semiconductor laser device according to the above invention, the cavity length is determined based on an approximate expression that minimizes the driving power corresponding to the desired optical output. It is characterized by that.

According to the sixth aspect of the invention, when determining the cavity length, the cavity length is determined based on an approximate expression that minimizes the driving power corresponding to the desired optical output.

According to a seventh aspect of the present invention, in the above-described semiconductor laser device, the active layer forming the resonator having the resonator length has a strained multiple quantum well structure.

According to a seventh aspect of the present invention, there is provided a semiconductor laser device having a strained multiple quantum well structure, wherein a strained multiple quantum well structure is applied as an active layer forming a resonator having the resonator length. Also, a desired optical output of 50 mW or more can be obtained with high optical power conversion efficiency or low driving power.

In the semiconductor laser device according to the present invention, the desired light output is 50 to 50.
400 mW and the resonator length is 1000
６００1600 μm.

According to the eighth aspect of the present invention, the desired light output is set in a range of 50 to 400 mW, the resonator length is set in a range of 1000 to 1600 μm, and only the relationship between the drive current and the light output is adjusted. Thus, a specific semiconductor laser device capable of giving a particular difference when the resonator length is determined from the above is realized.

According to a ninth aspect of the present invention, in the semiconductor laser device according to the above invention, the desired optical output is 50 to
200 mW, and the resonator length is 1000
４００1400 μm.

According to the ninth aspect of the present invention, the desired light output is set in a range of 50 to 200 mW, the resonator length is set in a range of 1000 to 1400 μm, and only the relationship between the drive current and the light output is adjusted. Thus, a specific semiconductor laser device capable of giving a particular difference when the resonator length is determined from the above is realized.

According to a tenth aspect of the present invention, there is provided a semiconductor laser device according to the above invention, wherein a constant optical output and a constant resonator length are used as parameters, and the driving power or the optical power conversion efficiency with respect to the impurity carrier concentration of the upper cladding layer. The upper cladding layer is set based on the relationship, and has the impurity carrier concentration set such that the driving power corresponds to a desired optical output and the driving power is near the minimum or the optical power conversion efficiency is near the maximum. .

According to the tenth aspect of the present invention, a desired light output is determined based on the relationship between the driving power and the impurity carrier concentration of the upper cladding layer, using a certain light output and a certain resonator length as parameters. By realizing a semiconductor laser device having the upper cladding layer in which the impurity carrier concentration is set such that the driving power is near the minimum or the optical power conversion efficiency is near the maximum corresponding to Conversion efficiency near the maximum, 50m
A desired light output of W or more can be obtained.

According to an eleventh aspect of the present invention, there is provided a semiconductor laser module, wherein the semiconductor laser device according to any one of the first to tenth aspects and a light for guiding a laser beam emitted from the semiconductor laser device to the outside. A fiber, and an optical coupling lens system that optically couples the semiconductor laser device and the optical fiber.

According to the eleventh aspect of the present invention, the first aspect
A semiconductor laser module having the semiconductor laser device according to any one of (1) to (10) is realized, and a desired optical output can be obtained with high optical power conversion efficiency or low driving power.

According to a twelfth aspect of the present invention, in the above-mentioned semiconductor laser module, the semiconductor laser module further comprises a temperature control device for controlling a temperature of the semiconductor laser device, wherein an optical fiber grating is formed near an incident end of the optical fiber. It is characterized by the following.

According to the twelfth aspect of the present invention, an optical fiber grating is formed near the incident end of the optical fiber, and a laser beam having a wavelength selected by the optical fiber grating is output.

According to a thirteenth aspect of the present invention, in the semiconductor laser module according to the above invention, a temperature control device for controlling the temperature of the semiconductor laser device, and a temperature control device disposed in the optical coupling lens system for reflecting light from the optical fiber side. An isolator for suppressing incidence of return light is further provided.

According to the thirteenth aspect of the present invention, the first aspect
A semiconductor laser module equipped with the semiconductor laser device according to any one of to 10 is realized, and even if the semiconductor laser module is equipped with a temperature control device, a desired optical output can be obtained with high optical power conversion efficiency or It can be obtained with low driving power.

According to a fourteenth aspect of the present invention, there is provided a method for manufacturing a semiconductor laser device, the method comprising: using a constant optical output as a parameter, including a cavity length of the semiconductor laser device and a carrier concentration of an upper cladding layer of the semiconductor laser device. A relationship obtaining step of obtaining a relationship between each element of the laser device and the driving power or optical power conversion efficiency of the semiconductor laser device; and a desired light output determined based on the relationship obtained by the relationship obtaining step. An element value determining step of determining each element value of the semiconductor laser device in which the driving power is near the minimum or the optical power conversion efficiency is near the maximum, and each element value determined by the element value determining step Forming a semiconductor laser device having the following.

According to the fourteenth aspect of the present invention, in the relation acquisition step, the semiconductor length including the cavity length of the semiconductor laser device and the carrier concentration of the upper cladding layer of the semiconductor laser device using a constant optical output as a parameter. The relationship between each element of the laser device and the drive power or optical power conversion efficiency of the semiconductor laser device is acquired, and the element value is determined based on the relationship acquired by the relationship acquisition step. Each element value of the semiconductor laser device in which the driving power is near the minimum or the light power conversion efficiency is near the maximum corresponding to the light output is determined, and each element determined by the element value determining step is determined by the forming step. A semiconductor laser device having a value is formed.

A method for manufacturing a semiconductor laser device according to a fifteenth aspect includes a relationship obtaining step of obtaining a relationship between a driving power and an optical output of 50 mW or more using a constant resonator length of 1000 μm or more as a parameter. The driving power corresponding to the desired optical output is determined based on the relationship obtained in the obtaining step, and the driving power corresponding to the desired optical output is near the minimum.
The method includes a resonator length determining step of determining a resonator length of m or more, and a forming step of forming a semiconductor laser device having the resonator length determined by the resonator length determining step.

According to the fifteenth aspect of the present invention, in the relation obtaining step, the relation of the driving power to the optical output of 50 mW or more with the constant resonator length of 1000 μm or more as a parameter is obtained. Determining a resonator length of 1000 μm or more that is determined based on the relationship obtained in the relationship obtaining step and at which the driving power corresponding to a desired optical output is near the minimum, and forming the resonator length by a forming step. A semiconductor laser device having a cavity length determined by the determining step is formed.

A method of manufacturing a semiconductor laser device according to claim 16 includes a relation obtaining step of obtaining a relation of optical power conversion efficiency with respect to a cavity length of 1000 μm or more with a constant light output of 50 mW or more as a parameter; Determined based on the relationship acquired by the relationship acquisition step,
Forming a resonator length determining step of determining a resonator length at which the optical power conversion efficiency corresponding to a desired optical output is close to a maximum value, and forming a semiconductor laser device having a resonator length determined by the resonator length determining step And a forming step.

According to the sixteenth aspect of the present invention, the relationship obtaining step obtains the relationship between the optical power conversion efficiency and the cavity length of 1000 μm or more with the constant optical output of 50 mW or more as a parameter, and determines the cavity length. Determining a resonator length at which the optical power conversion efficiency corresponding to a desired optical output is close to a maximum value, the resonator length being determined based on the relationship obtained by the relationship obtaining step. A semiconductor laser device having a cavity length determined by the device length determining step is formed.

According to a seventeenth aspect of the present invention, in the method for manufacturing a semiconductor laser device according to the above invention, the optical power conversion is performed in accordance with the desired optical output based on the relationship obtained in the relationship obtaining step. The method further includes an approximate expression calculating step of obtaining an approximate expression that maximizes efficiency, and wherein the resonator length determining step determines the resonator length based on the approximate expression.

According to the seventeenth aspect of the present invention, the approximate expression calculating step determines that the optical power conversion efficiency is maximum corresponding to the desired optical output based on the relation acquired in the relation acquiring step. An approximate expression is obtained, and the resonator length determining step determines the resonator length based on the approximate expression.

A method for manufacturing a semiconductor laser device according to claim 18 is a relation obtaining step of obtaining a relation of a driving power with respect to a cavity length of 1000 μm or more using a constant optical output of 50 mW or more as a parameter, 1000 μm, which is determined based on the relationship obtained in the obtaining step, and in which the driving power for the desired optical output is near the minimum.
The method includes a resonator length determining step of determining the above resonator length, and a forming step of forming a semiconductor laser device having the resonator length determined by the resonator length determining step.

According to the eighteenth aspect of the present invention, the relationship obtaining step obtains the relationship between the drive power and the resonator length of 1000 μm or more with the constant optical output of 50 mW or more as a parameter. , Which is determined based on the relationship acquired in the relationship acquiring step, and in which the driving power for the desired optical output is near the minimum.
A cavity length of 000 μm or more is determined, and a semiconductor laser device having the cavity length determined by the cavity length determining step is formed by the forming step.

According to a nineteenth aspect of the present invention, in the above method, the semiconductor laser device according to the present invention is arranged so as to correspond to the desired light output based on the relationship acquired in the relationship acquiring step. The method further includes an approximate expression calculating step of obtaining an approximate expression that minimizes the driving power, and the resonator length determining step determines the resonator length based on the approximate expression.

According to the nineteenth aspect of the present invention, the approximation formula calculating step includes the step of minimizing the driving power corresponding to the desired light output based on the relation obtained in the relation obtaining step. Is obtained, and the resonator length determining step determines the resonator length based on the approximate expression.

According to a twentieth aspect of the present invention, in the above method, the active layer forming the resonator having the resonator length has a strained multiple quantum well structure.

According to the twentieth aspect of the present invention, there is provided a semiconductor laser device having a strained multiple quantum well structure, wherein a strained multiple quantum well structure is applied as an active layer forming a resonator having the resonator length. Also, a desired optical output of 50 mW or more can be obtained with high optical power conversion efficiency or low driving power.

According to a twenty-first aspect of the present invention, in the method of manufacturing a semiconductor laser device, a relationship between the driving power and the impurity carrier concentration of the upper cladding layer is obtained by using a constant optical output and a constant resonator length as parameters. And a carrier concentration determination step of determining the impurity carrier concentration, which is determined based on the relationship acquired in the relationship acquisition step and corresponds to a desired optical output and has a drive power near the minimum, and Forming a semiconductor laser device in which the impurity carrier concentration is set to the impurity carrier concentration determined in the carrier concentration determining step.

According to the twenty-first aspect of the present invention, the relationship between the driving power and the impurity carrier concentration in the upper cladding layer is acquired by using the constant light output and the constant resonator length as parameters in the relationship acquiring step. The determining step determines the impurity carrier concentration determined based on the relationship obtained in the relationship obtaining step and corresponding to a desired optical output and having a driving power near the minimum, and forming the upper cladding layer by the forming step. A semiconductor laser device is formed in which the impurity carrier concentration is set to the impurity carrier concentration determined in the carrier concentration determining step.

The semiconductor laser device according to claim 22 has a front end face and a rear end face, and has a resonator length of about 900 μm.
a resonator having a length from m to about 1800 μm, an active layer stacked in the resonator, connected to two electrodes receiving a bias potential from a power supply, and receiving a current,
A low reflection film having a reflectance of about 4% or less and coated on the front end face, a high reflection film having a reflectance of about 80% or more and coated on the rear end face, and being connected to the electrode; A power supply that supplies an amount of power that causes the semiconductor laser device to generate an optical output that is equal to or less than a specific upper boundary and equal to or greater than a specific lower boundary based on the resonator length,
The specific upper boundary is approximately 1000 μm and approximately 1380 μm
50 mW for a resonator length between
Assuming that the resonator length is L for a resonator length between 0 μm and 1480 μm, (1 mW) * [(L−1280 μm)
/ 2 μm], from about 1480 μm to about 1700 μm.
(1 mW) * [(L-
1260 μm) /2.2 μm], which is approximately 1700 μm.
The value is (2 mW) * [(L-1600 μm) / 1 μm] for a cavity length between μm and approximately 1750 μm, and (3 mW) for a cavity length between approximately 1750 μm and approximately 1770 μm. * [(L-1510 μm) /
2 μm], and the specific lower boundary is approximately 100
For resonator lengths between 0 μm and approximately 1050 μm, (2
mW) * [(L−950 μm) / 1 μm],
The value is (2 mW) * [(L−750 μm) / 3 μm] for a resonator length between approximately 1050 μm and approximately 1200 μm, and (2 mW) for a resonator length between approximately 1200 μm and approximately 1350 μm. ) * [(L-450 μm) / 5 μ
m], and (3 mW) * [(L−150 μm) for a resonator length between approximately 1350 μm and approximately 1450 μm.
m) / 10 μm], which is approximately 1450 μm and approximately 17
It is characterized by a value of 390 mW for a resonator length between 70 μm.

According to the twenty-second aspect of the present invention, the specific upper boundary is 50 mW for a resonator length between approximately 1000 μm and approximately 1380 μm, and a resonator length between approximately 1380 μm and 1480 μm. (1 mW) * [(L-1280 μm) / 2 μ
m], and (1 mW) * [(L-126) for a cavity length between approximately 1480 μm and approximately 1700 μm.
0 μm) /2.2 μm] for a resonator length between approximately 1700 μm and approximately 1750 μm.
W) * [(L-1600 μm) / 1 μm],
(3 mW) * [(L-1510 μm) / 2 μ for a cavity length between approximately 1750 μm and approximately 1770 μm
m], and the specific lower boundary is approximately 1000 μm.
m and approximately 1050 μm for a resonator length of (2 m
W) * [(L−950 μm) / 1 μm], and for a resonator length between approximately 1050 μm and approximately 1200 μm, (2 mW) * [(L−750 μm) / 3 μm] For a resonator length between approximately 1200 μm and approximately 1350 μm, (2 mW) * [(L−450 μm) / 5 μm
m], and (3 mW) * [(L−150 μm) for a resonator length between approximately 1350 μm and approximately 1450 μm.
m) / 10 μm], which is approximately 1450 μm and approximately 17
The value is 390 mW with respect to the cavity length between 70 μm, and the semiconductor laser device outputs an optical output Pout that is equal to or less than a specific upper boundary and equal to or greater than a specific lower boundary based on the cavity length. Power is supplied.

A semiconductor laser device according to a twenty-third aspect has a front end face and a rear end face, and has a resonator length of about 900 μm.
a resonator having a length from m to about 1800 μm; an active layer laminated in the resonator; a low-reflection film having a reflectance of about 4% or less and coated on the front end face;
A high reflection film having a reflectance of about 80% or more and being coated on the rear end face;
An optical output Pout that is equal to or less than a specific upper boundary based on the resonator length and equal to or greater than a specific lower boundary is output, and the specific lower boundary has a cavity length between approximately 1000 μm and approximately 1380 μm. 50 mW, approximately 1380 μm
(1 mW) * [(L−1280 μm) / 2 μ for a resonator length between 1 and 1480 μm.
m], and (1 mW) * [(L-126) for a cavity length between approximately 1480 μm and approximately 1700 μm.
0 μm) /2.2 μm] for a resonator length between approximately 1700 μm and approximately 1750 μm.
W) * [(L-1600 μm) / 1 μm],
(3 mW) * [(L-1510 μm) / 2 μ for a cavity length between approximately 1750 μm and approximately 1770 μm
m], and the specific lower boundary is approximately 1000 μm.
m and approximately 1050 μm for a resonator length of (2 m
W) * [(L-950 μm) / 1 μm], and for a resonator length between approximately 1050 μm and approximately 1200 μm, (2 mW) * [(L−750 μm) / 3 μm], For a resonator length between approximately 1200 μm and approximately 1350 μm, (2 mW) * [(L−450 μm) / 5 μm
m], and (3 mW) * [(L−150 μm) for a resonator length between approximately 1350 μm and approximately 1450 μm.
m) / 10 μm], which is approximately 1450 μm and approximately 17
It is characterized by a value of 390 mW for a resonator length between 70 μm.

According to the twenty-third aspect of the present invention, the specific lower boundary is 50 mW with respect to a resonator length between approximately 1000 μm and approximately 1380 μm, and a resonator length between approximately 1380 μm and 1480 μm. (1 mW) * [(L-1280 μm) / 2 μ
m], and (1 mW) * [(L-126) for a cavity length between approximately 1480 μm and approximately 1700 μm.
0 μm) /2.2 μm] for a resonator length between approximately 1700 μm and approximately 1750 μm.
W) * [(L-1600 μm) / 1 μm],
(3 mW) * [(L-1510 μm) / 2 μ for a cavity length between approximately 1750 μm and approximately 1770 μm
m], and the specific lower boundary is approximately 1000 μm.
m and approximately 1050 μm for a resonator length of (2 m
W) * [(L-950 μm) / 1 μm], and for a resonator length between approximately 1050 μm and approximately 1200 μm, (2 mW) * [(L−750 μm) / 3 μm], For a resonator length between approximately 1200 μm and approximately 1350 μm, (2 mW) * [(L−450 μm) / 5 μm
m], and (3 mW) * [(L−150 μm) for a resonator length between approximately 1350 μm and approximately 1450 μm.
m) / 10 μm], which is approximately 1450 μm and approximately 17
The value is 390 mW with respect to the cavity length between 70 μm, and the semiconductor laser device outputs an optical output Pout that is equal to or less than a specific upper boundary and equal to or greater than a specific lower boundary based on the cavity length. To be selected.

According to a twenty-fourth aspect of the present invention, in the above-mentioned invention, the semiconductor laser device operates at an optical output level Pout between about 50 mW and about 100 mW. The resonator length is approximately 1000 μm and approximately ｛2 μm * (Pout / 1 m
W) +1280 μm｝.

According to the twenty-fourth aspect of the present invention, the semiconductor laser device is operated at an optical output level Pout between about 50 mW and about 100 mW, and the length of the resonator is reduced. , Approximately 1000 μm and approximately ｛2 μm *
(Pout / 1 mW) +1280 μm}, and the semiconductor laser device can be operated optimally.

According to a twenty-fifth aspect of the present invention, in the above-mentioned invention, the semiconductor laser device operates at an optical output level Pout between about 100 mW and about 200 mW. And the resonator length is approximately ｛1 μm * (Pout / 2 mW) +950 μm
m} and approximately {2.2 μm * (Pout / 1 mW) +1260
μm｝.

According to the twenty-fifth aspect, the semiconductor laser device is operated at an optical output level Pout between about 100 mW and about 200 mW, and the length of the resonator is , Approximately ｛1 μm * (Pout / 2m
W) +950 μm} and approximately {2.2 μm * (Pout / 1 m
W) +1260 μm}, and the semiconductor laser device can be operated optimally.

According to a twenty-sixth aspect of the present invention, in the above-mentioned invention, the semiconductor laser device operates at a light output level Pout between about 200 mW and about 300 mW in the amount of electric power applied to the electrode. And the resonator length is approximately ｛3 μm * (Pout / 2 mW) +750 μm
m} and approximately {1μm * (Pout / 2mW) + 1600μ
m｝.

According to the twenty-sixth aspect of the present invention, the semiconductor laser device is operated at an optical output level Pout between about 200 mW and about 300 mW, and the resonator length is , Approximately ｛3 μm * (Pout / 2m
W) +750 μm} and approximately {1 μm * (Pout / 2 mW)
+1600 μm}, and the semiconductor laser device can be operated optimally.

According to a twenty-seventh aspect of the present invention, in the semiconductor laser device according to the above invention, the semiconductor laser device operates at an optical output level Pout between about 300 mW and about 360 mW. And the resonator length is approximately ｛5 μm * (Pout / 2 mW) +450 μm
m｝ and approximately 1750 μm.

According to the twenty-seventh aspect of the present invention, the semiconductor laser device is operated at an optical output level Pout between about 300 mW and about 360 mW, and the resonator length is , About $ 5m * (Pout / 2m
W) Between +450 μm and approximately 1750 μm, the semiconductor laser device can be operated optimally.

According to a twenty-eighth aspect of the present invention, in the above-described semiconductor laser device, the semiconductor laser device operates at an optical output level Pout between about 360 mW and about 390 mW. And the resonator length is approximately {10 μm * (Pout / 3 mW) +150 μm
m} and approximately {2μm * (Pout / 3mW) + 1510μ
m｝.

According to the twenty-eighth aspect of the present invention, the semiconductor laser device is operated at an optical output level Pout between about 360 mW and about 390 mW, and the resonator length is , Approximately ｛10 μm * (Pout / 3
mW) +150 μm and approximately {2 μm * (Pout / 3 m
W) +1510 μm}, and the semiconductor laser device can be operated optimally.

Further, in the semiconductor laser device according to claim 29, in the above-mentioned invention, the resonator length is approximately 100
0 μm and approximately 1100 μm, and the amount of electric power applied to the electrode is applied to the electrode for operating the semiconductor laser device at an optical output level Pout between approximately 50 mW and approximately 100 mW. I do.

According to the twenty-ninth aspect of the present invention, the length of the resonator is between approximately 1000 μm and approximately 1100 μm, and the amount of power applied to the electrode is approximately 50 mW and approximately 100 μm.
The power is applied to the electrode for operating the semiconductor laser device at a light output level Pout of between mW and mW.

Further, in the semiconductor laser device according to claim 30, in the above invention, the resonator length is approximately 120
0 μm and approximately 1600 μm, and the amount of power applied to the electrode is applied to the electrode for operating the semiconductor laser device at an optical output level Pout between approximately 200 mW and approximately 300 mW. I do.

According to the thirtieth aspect of the present invention, the resonator length is between approximately 1200 μm and approximately 1600 μm, and the amount of power applied to the electrode is approximately 200 mW and approximately 30 μm.
An optical output level Pout between 0 mW is applied to the electrode for operating the semiconductor laser device.

[0071]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a semiconductor laser device, a method of manufacturing the same, and a semiconductor laser module according to the present invention will be described below with reference to the accompanying drawings.

(Embodiment 1) First, Embodiment 1 of the present invention will be described. FIG. 1 is an oblique cutaway view showing a schematic configuration of a semiconductor laser device according to a first embodiment of the present invention. FIG. 2 is a longitudinal sectional view in the longitudinal direction of the semiconductor laser device shown in FIG. Further, FIG.
FIG. 3 is a sectional view taken along line AA of the semiconductor laser device shown in FIG. 2. 1 to 3, the semiconductor laser device 20
Are sequentially formed on the (100) plane of the n-InP substrate 1 by n-
N serving as both a buffer layer of InP and a lower cladding layer
-InP clad layer 2, GRIN-SC with compressive strain
H-MQW (Graded Index-Separate Confinement Hete
rostructure Multi Quantum Well) active layer 3 and p
-InP clad layer 6 and p-InGaAsP cap layer 7 are laminated.

A part of the p-InP cladding layer 6, GRIN
-The upper portions of the SCH-MQW active layer 3 and the n-InP cladding layer 2 are processed into a mesa stripe shape, and the p-InP blocking layer 8 and the n-InP blocking layer formed as current blocking layers are formed on both sides of the mesa stripe. Embedded by layer 9. Also, p-InGaAs
A p-side electrode 10 is formed on the upper surface of the sP cap layer 7, and an n-side electrode 11 is formed on the back surface of the n-InP substrate 1.

On the light reflecting end face, which is one end face in the longitudinal direction of the semiconductor laser device 20, a reflective film 14 having a high light reflectivity of 80% or more is formed. The emission side reflection film 15 having a low light reflectance of 1 to 5% is formed. GRIN-SCH-MQ of the optical resonator formed by the reflection film 14 and the emission-side reflection film 15
The light generated in the W active layer 3 is reflected by the reflection film 14 and is emitted as laser light via the emission-side reflection film 15.

Here, the resonator length L is GRIN-SCH
-The length in the longitudinal direction of the MQW active layer 3,
m or more. The light output from the semiconductor laser device 20 is set to 50 mW or more.

The resonator length L of the semiconductor laser device shown in FIG. 1 is determined based on the relationship shown in FIG. FIG.
FIG. 4 is a diagram illustrating a relationship between a light output and a driving power using a resonator length as a parameter. FIG. 4 assumes that the resonator length is 800 μm, 1000 μm, 1300 μm, 1500 μm on the assumption that the semiconductor laser device 20 has the structure shown in FIG.
3 shows the relationship between the optical output and the driving power when m and 1800 μm are set.

In FIG. 4, a semiconductor laser device having a short resonator length generally requires a larger driving power to obtain a constant optical output than a semiconductor laser device having a long resonator length. However, the cavity length is 1500 μm and 180 μm.
When compared with 0 μm, the optical output is around 420 mW (P1)
In the case where an optical output of 420 mW or more is obtained, a 1800 μm semiconductor laser device having a long cavity length requires lower driving power. Similarly, if the resonator length is 130
Compared with 0 μm and 1800 μm, the light output is 350 m
It can be seen that in the case of reversing near W (P2) and obtaining an optical output of 350 mW or more, a 1800 μm semiconductor laser device having a long resonator length requires lower drive power. Furthermore, when the cavity length is compared with 1000 μm and 1800 μm, the optical output is reversed around 250 mW (P3), and when an optical output of 250 mW or more is obtained, the 1800 μm semiconductor laser device having a longer cavity length has a lower drive. It turns out that only electric power is enough. That is, when obtaining a constant optical output, the value of the constant optical output changes the optimum value of the resonator length at which the driving power is minimized.

Here, considering the case where the cavity length is selected based on the relationship between the conventional optical output and the driving current shown in FIG. 14, the semiconductor laser device having a small driving current conventionally requires a driving power of Is considered to be a small semiconductor laser device, the cavity length is set to 800 μm and the optical output is increased from about 220 mW to about 350 m until the optical output is about 220 mW.
Up to mW, the resonator length is set to 1000 μm, and when the optical output is from about 350 μm to about 380 μm, the resonator length is set to 130 μm.
0 μm, and when the optical output is from about 380 mW to about 420 mW, the cavity length is 1500 μm and the optical output is about 420 mW.
At mW or more, the cavity length was set to 1800 μm, and the cavity length that increased as the optical output increased was determined.

Therefore, for example, when the light output is 360 m
In the case of obtaining a semiconductor laser device of W, conventionally, the cavity length was determined to be 1300 μm, but in this case,
Actually, based on the relationship shown in FIG.
When the diameter is set to 00 μm, the driving can be performed with a small driving power. Therefore, an inappropriate resonator length is determined and determined.

On the other hand, in Embodiment 1, FIG.
As shown in the figure, the resonator length having the smallest drive power among the resonator lengths that can obtain a desired optical output is set based on the relationship between the optical power and the drive power with the resonator length as a parameter. Since the selection is determined, it is possible to realize a semiconductor laser device having a small driving power at all times.

In the first embodiment, when a desired optical output is obtained by the semiconductor laser device 20 using the GRIN-SCH-MQW active layer 3 having a compressive strain, the resonator having the minimum drive power is required. Although the length is determined, the present invention is not limited to this, and can be applied to a semiconductor laser device having another structure.

Here, a method for manufacturing the semiconductor laser device according to the first embodiment of the present invention will be described with reference to a flowchart shown in FIG. In FIG. 5, first,
The relationship between the drive power and the optical output with the resonator length as a parameter, that is, the relationship shown in FIG.
It is obtained from 0 (step S101). Thereafter, a desired optical output is set (step S102), and a resonator length having a minimum drive power corresponding to the set desired optical output is determined (step S103). Thereafter, a semiconductor laser device having the determined resonator length is manufactured (step S104), and the process ends.

In the first embodiment, the resonator length is set to 800 μm, 1000 μm, 1300 μm, 150 μm,
The five parameters of 0 μm and 1800 μm have been described. However, the present invention is not limited to this. For other resonator lengths, the relationship between the optical output and the driving power is obtained or complemented.
A more detailed resonator length may be determined with high accuracy. In this case, when determining the resonator length, the resonator length corresponding to the predetermined drive power or less may be determined instead of determining the resonator length corresponding to the minimum drive power.

Further, in the first embodiment described above, FIG.
Although the characteristic curve shown in (1) is supplemented with specific experimental values by theoretical values, more experimental values may be obtained to increase the certainty.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described. In the first embodiment described above, based on the relationship between the optical output and the driving power shown in FIG.
In order to obtain a desired optical output, the resonator length that minimizes the driving power is determined. However, in the second embodiment, the relationship between the optical power conversion efficiency and the resonator length is determined by using the optical output as a parameter. To obtain the desired light output,
The resonator length corresponding to the maximum optical power conversion efficiency is determined.

As shown in FIG. 6, when the relationship between the optical power conversion efficiency and the cavity length is obtained using the optical output as a parameter, there is an optimum value at which the optical power conversion efficiency is maximized for each optical output. Therefore, by determining the resonator length corresponding to the point where the optical power conversion efficiency with respect to the desired optical power becomes the maximum, the resonator length at which the optical power conversion efficiency becomes the maximum can be determined. With a semiconductor laser device having such a configuration, a semiconductor laser device having high optical power conversion efficiency can be realized. In addition, high optical power conversion efficiency means that drive power is minimum.

For example, in FIG. 6, when obtaining an optical output of 360 mW, the maximum value of the optical power conversion efficiency is 0.15
And the resonator length at that time is 1500 μm. Therefore, by setting the cavity length to 1500 μm, it is possible to realize a 360 mW optical output semiconductor laser device with the highest optical power conversion efficiency. Also, 50mW
When the optical output of the optical power conversion is obtained, the maximum value of the optical power conversion efficiency is 0.
34, and the resonator length at that time is 1000 μm. Therefore, by setting the cavity length to 1000 μm, it is possible to realize a semiconductor laser device having the highest optical power conversion efficiency and a light output of 50 mW.

Here, a method of manufacturing the semiconductor laser device according to the second embodiment of the present invention will be described with reference to a flowchart shown in FIG. In FIG. 7, first,
The relationship between the optical power conversion efficiency and the cavity length, that is, the relationship shown in FIG. 6 with the constant optical output as a parameter, is acquired from the database 30 (step S201). Thereafter, a desired light output is set (step S20).
2) A resonator length corresponding to the set desired optical output and having a maximum or near optical power conversion efficiency is determined (step S203). Thereafter, a semiconductor laser device having the determined cavity length is manufactured (step S20).
4), end this processing.

An approximate expression L1 showing the relationship between the cavity length and the optical output is obtained based on the relationship between the cavity length and the optical output at which the optical power conversion efficiency is maximized as shown in FIG. The resonator length may be determined based on the approximate expression L1.
This approximation formula L1 relates the obtained maximum value by a predetermined approximation method. In this approximation L1, the relationship between the optical output and the optimal resonator length is shown. Therefore, by inputting a desired optical output value, the optimal resonator length can be immediately obtained.

In the second embodiment described above, the resonator length at which the optical power conversion efficiency is maximized is determined. However, the present invention is not limited to this. It may be determined, or the resonator length at which the optical power conversion efficiency is close to the maximum may be determined.
The range near the maximum value may be a resonator length within a range defined by a predetermined percentage corresponding to the maximum value of the optical power conversion efficiency, and may be determined based on the resonator length corresponding to the maximum value of the optical power conversion efficiency. The length of the resonator may be within a range defined by the percentage. Further, a predetermined margin may be provided for the resonator length obtained by the approximate expression L1. This margin corresponds to a range near the maximum value.

(Embodiment 3) Next, Embodiment 3 of the present invention will be described. In the second embodiment, when a desired optical output is obtained based on the relationship between the optical power conversion efficiency and the cavity length using the optical output as a parameter,
Although the resonator length at which the optical power conversion efficiency is maximized is determined, in the third embodiment, a desired optical output is determined based on the relationship between the resonator length and the driving power using the optical output as a parameter. Is obtained, the resonator length that minimizes the driving power is determined. That is, Embodiment 2
The optical power conversion efficiency is substantially the same drive power.

FIG. 8 shows a constant light output as a parameter,
FIG. 5 is a diagram illustrating a relationship between a driving power and a resonator length. FIG.
Then, contrary to the optical power conversion efficiency shown in FIG. 6, the driving power has a characteristic having a minimum value. In FIG. 8, each optical output has a resonator length at which the drive power has a minimum value. In particular, as the light output increases, the minimum value appears remarkably. For example, when the optical output is 360 mW, the minimum value of the driving power is 2.4 W, and the resonator length at this time is 1500 μm. In this way, the resonator length that minimizes the driving power for the desired optical output can be determined.

Here, a method of manufacturing a semiconductor laser device according to the third embodiment of the present invention will be described with reference to a flowchart shown in FIG. In FIG. 9, first,
The relationship between the drive power and the resonator length with the constant optical output as a parameter, that is, the relationship shown in FIG. 8 is acquired from the database 30 (step S301). afterwards,
A desired optical output is set (step S302), and a resonator length corresponding to the set desired optical output and having a minimum or near minimum drive power is determined (step S302).
303). Thereafter, a semiconductor laser device having the determined resonator length is manufactured (step S304), and the process ends.

An approximate expression L2 showing the relationship between the cavity length and the optical output is obtained based on the relationship between the optical cavity and the cavity length at which the driving power is minimized as shown in FIG. The resonator length may be determined based on L2. This approximation formula L2 relates the obtained minimum value by a predetermined approximation method. In this approximation formula L2, the relationship between the optical output and the optimum resonator length is shown. Therefore, by inputting a desired optical output value, the optimum resonator length can be immediately obtained.

In the third embodiment, the resonator length at which the driving power is minimized is determined.
The present invention is not limited to this, and a resonator length equal to or less than a predetermined drive power may be determined, or a resonator length at which the drive power is near the minimum may be determined. The range near the minimum value may be a resonator length within a range defined by a predetermined percentage corresponding to the minimum drive power, or specified by a predetermined percentage based on the resonator length corresponding to the minimum drive power. The resonator length may be in the range described above. Further, a predetermined margin may be provided for the resonator length obtained by the approximate expression L2. This margin corresponds to the range near the minimum value.

In the first to third embodiments described above, the resonator length has been described as being at most 1800 μm.
However, the present invention is not limited to this, and can be similarly applied to a longer resonator length. In particular, when it is desired to increase the optical output, a longer cavity length is required. In this case, the driving power of the semiconductor laser device 20 becomes large, and the operation and effect shown in this embodiment are further improved. Is considered to appear.

(Embodiment 4) Next, Embodiment 4 of the present invention will be described. Embodiments 1 to 3 described above
In each of the above embodiments, the resonator length at which the driving power is minimum or the optical power conversion efficiency is maximum is obtained from the desired optical output. However, in the fourth embodiment, the desired optical output and the constant resonance are obtained. The Zn carrier concentration of the upper clad layer (p-InP clad layer 6) that minimizes the driving power is determined from the device length.

FIG. 10 is a diagram showing the relationship between the driving power and the Zn carrier concentration in the upper cladding layer, using a constant optical output and a constant resonator length as parameters. In FIG. 10, there is a Zn carrier concentration in the upper cladding layer where the value of the driving power is minimum for a combination of a fixed resonator length of 800 μm or 1000 μm and a fixed optical output such as 150 mW, 170 mW or 190 mW. As shown in FIG. 20, a constant optical output and a constant resonator length are used as parameters, and Z
When the relationship between the drive current and the n carrier concentration is obtained, Z
As the n carrier concentration increases, the driving current monotonically increases, and there is no optimum value. That is,
From the viewpoint of driving power, it can be seen that the Zn carrier concentration has a minimum value.

Therefore, it is possible to determine the Zn carrier concentration of the upper cladding layer that can minimize the driving current for a desired optical output and a constant resonator length. It is to be noted that the drive current can be further reduced by optimizing the resonator length, as described in the first to third embodiments.

For example, when the desired optical output is 190 mW, and when the cavity length is 800 μm, the Zn carrier concentration of the upper cladding layer where the driving power is minimum is Cz, and the driving power at this time is 1 .2W. In this case, the drive power is 1.1 W by setting the resonator length to 1000 μm.

Here, a method for manufacturing a semiconductor laser device according to the fourth embodiment of the present invention will be described with reference to the flowchart shown in FIG. In FIG. 11, first, the relationship between the Zn carrier concentration of the upper cladding layer and the driving power, that is, the relationship shown in FIG. 10, using the constant optical output and the constant resonator length as parameters, is acquired from the database 30 (step S10). S401). afterwards,
A desired optical output and a constant resonator length are set (step S402), and a Zn carrier concentration corresponding to the set desired optical output and the constant resonator length and having a minimum or near-minimum driving power is set. (Step S4)
03). After that, a semiconductor laser device having the determined Zn carrier concentration is manufactured (step S404), and the process ends.

The relationship between the Zn carrier concentration, the optical output, and the resonator length is shown on the basis of the relationship between the Zn carrier concentration at which the driving power is minimized and the optical output and the resonator length shown in FIG. From the approximate expression shown below, Z
The n carrier concentration may be determined. This approximation formula is obtained by associating the obtained minimum values with a predetermined approximation method. In this approximation, the relationship between the combination of the optical output and the resonator length and the optimum Zn carrier concentration is shown. Therefore, by inputting a desired optical output and a constant resonator length value, the optimum Zn carrier concentration can be obtained. Can be requested immediately.

In the fourth embodiment, the optimum Zn carrier concentration is obtained based on the relationship between the Zn carrier concentration and the driving power. However, the present invention is not limited to this.
As in the second embodiment, the relationship between the optical power conversion efficiency and the Zn carrier concentration is determined by using the constant optical output and the constant resonator length as parameters, and the Zn carrier concentration at which the optical power conversion efficiency is maximized is determined. You may.

In the fourth embodiment, the Zn carrier concentration at which the driving power is minimized is determined. However, the present invention is not limited to this, and the Zn carrier concentration at a predetermined driving power or less may be determined. Alternatively, the Zn carrier concentration at which the driving power is close to the minimum may be determined. The range near the minimum value may be a Zn carrier concentration within a range defined by a predetermined percentage corresponding to the minimum drive power, or specified by a predetermined percentage based on the Zn carrier concentration corresponding to the minimum drive power. Within the specified range
The carrier concentration may be used. Further, a predetermined margin may be provided for the Zn carrier concentration obtained by the approximate expression. This margin corresponds to the range near the minimum value.

In the first to fourth embodiments, the resonator length of the semiconductor laser device 20 or the Zn carrier concentration of the upper cladding layer in which the driving power is at or near the minimum or the optical power conversion efficiency is at or near the maximum. Is determined, but the present invention is not limited to this, and various elements of the semiconductor laser device 20 may be determined in a similar manner. For example, the value of the reflectance of the reflection film 14 or the emission side reflection film 15 of the semiconductor laser device 20 may be determined.

Here, from the results of the above-described first to fourth embodiments, the semiconductor laser devices shown in the first to fourth embodiments are generally III-V group semiconductor lasers having the following conditions. I can say that. That is, first, about 1000 μm
And a cavity length L ranging from about 1800 μm to about 1800 μm, and a resonator structure having an end face on the reflection film 14 side and an end face on the emission side reflection film 15 is formed. Second, two electrodes having an active layer in the resonator structure and receiving a bias from a power supply are coupled. Third, the emission side reflection film 15 has a low reflectance of about 4% or less. Fourth, the reflection film 14 has a high reflectance of about 80% or more. Fifth, the hole carrier concentration of the upper cladding layer formed on the active layer, preferably Z
The hole carrier concentration by doping n is 4 × 10 ¹⁷ cm ^-3
From 1 × 10 ¹⁸ cm ^{−3 to,} for example, 7 × 10 ¹⁷ cm ⁻³ . Here, this III-V group semiconductor laser has one or more GaAs, InGa
As, AlGaAs, InGaAsP, InP, GaI
nNAs, AlGaInAs, AlGaInAsP, A
1GaInP, GaAsSb, or the like is used.

FIG. 12 shows that for a given optical output between 50 mW and 390 mW about 5% of the minimum drive power
The input drive power can be in the range of 10% to 10% and / or can be in the range of about 5% to 10% of the maximum light power conversion efficiency for a given light output II.
The range of the cavity length L of the IV semiconductor laser is shown. The point outside this area is a point P1 having the following values:
ＰP12 (see FIG. 12). That is, point resonator length Optical output value P1 1380 μm 50 mW P2 1480 μm 100 mW P3 1700 μm 200 mW P4 1750 μm 300 mW P5 1750 μm 360 mW P6 1770 μm 390 mW P7 1450 μm PW 1300 μm Line segments 540 to 551 connecting the points P1 to P12 are defined as external lines of the region. Here, the line segments 547 to 551 indicate the lower boundary (left side in the drawing) of the resonator length, and the line segment 541
545 indicate the upper boundary (right side in the figure) of the resonator length.
FIG. 12 also shows a preferable operation range of the optical output with respect to the cavity length given to the III-V semiconductor laser. In this case, the line segments 540 to 545
Indicates a lower boundary (bottom side) of the light output, and line segments 546 to 551 indicate an upper boundary (upper side) of the light output.

The line segments 540 to 540 shown in FIG.
551 can be mathematically defined by an expression that can be expressed as a function of the resonator length L or a function of the optical output Pout. 1) Line segment 540 Resonator length L span: 1000 μm to 1380 μm Optical output Pout span: 50 mW to 50 mW L = [1000 μm, 1380 μm] (1A) Pout = 50 mW (1B) 2) Line segment 541 Resonator length L span: 1380 μm １４1480 μm Optical output Pout span: 50 mW to 100 mW L = (100 μm / 50 mW) * Pout + 1280 μm (2A) = 2 μm * (Pout / 1 mW) +1280 μm (2B) Pout = (1 mW) * [(L−1280 μm) / 2 μm] ( 2C) 3) Line segment 542 Resonator length L span: 1480 μm to 1700 μm Optical output Pout span: 100 mW to 200 mW L = (220 μm / 100 mW) * Pout + 1260 μm (3A) = 2.2 μm * (Pout / 1 mW) +1260 μm (3B) P out = (1 mW) * [(L-1260 μm) /2.2 μm] (3C) 4) Line segment 543 Resonator length L span: 1700 μm to 1750 μm Optical output Pout span: 200 mW to 300 mW L = (50 μm / 100 mW) * Pout + 1600 μm (4A) = 1 μm * (Pout / 2 mW) +1600 μm (4B) Pout = (2 mW) * [(L-1600 μm) / 1 μm] (4C) 5) Line segment 544 Resonator length L span: 1750 μm to 1750 μm Pout span: 300 mW to 360 mW L = 1750 μm (5A) Pout = [300 mW, 360 mW] (5B) 6) Line segment 545 Resonator length L span: 1750 μm to 1770 μm Optical output Pout span: 360 mW to 390 mW L = (20 μm / 30 mW ) * Pout + 1510 μm (6A) = 2 μm * (Pout / 3 mW) +1510 μm (6B) Pout = (3 mW) * [(L−1510 μm) / 2 μm] (6C) 7) Line segment 546 Resonator length L span: 1450 μm to 1770 μm Optical output Pout Span: 390 mW to 390 mW L = [1450 μm, 1770 μm] (7A) Pout = 390 mW (7B) 8) Line segment 547 Resonator length L span: 1350 μm to 1450 μm Optical output Pout span: 360 mW to 390 mW L = (100 μm / 30 mW) * Pout + 150 μm (8A) = 10 μm * (Pout / 3 mW) +150 μm (8B) Pout = (3 mW) * [(L−150 μm) / 10 μm] (8C) 9) Line segment 548 Resonator length L span: 1200 μm to 1350 μm Light Output Pout span: 300mW ~ 60 mW L = (150 μm / 60 mW) * Pout + 450 μm (9A) = 5 μm * (Pout / 2 mW) +450 μm (9B) Pout = (2 mW) * [(L−450 μm) / 5 μm] (9C) 10) Line segment 549 Resonator Long L span: 1050 μm to 1200 μm Optical output Pout span: 200 mW to 300 mW L = (150 μm / 100 mW) * Pout + 750 μm (10 A) = 3 μm * (Pout / 2 mW) +750 μm (10B) Pout = (2 mW) * [(L−750 μm ) / 3 μm] (10C) 11) Line segment 550 Resonator length L span: 1000 μm to 1050 μm Optical output Pout span: 100 mW to 200 mW L = (50 μm / 100 mW) * Pout + 950 μm (11A) = 1 μm * (Pout / 2 mW) +950 μm (11B) Pout (2 mW) * [(L-950 μm) / 1 μm] (11C) 12) Line segment 551 Resonator length L span: 1000 μm to 1000 μm Optical output Pout span: 50 mW to 100 mW L = 1000 μm (12A) Pout = [50 mW, 100 mW ] (12B)

The area is 50 mW, 100 mW, 200 m
Includes the six series of data shown in FIGS. 6 and 8 taken for optical powers of W, 300 mW, 360 mW, and 390 mW. These six sets of data are shown in FIG.
Are shown as line segments 501-506.

The desired resonator length L is divided into nine as shown in FIG. In FIG. 13, "~" indicates
"About" means. The values of the optical output Pout in these nine sections are divided by the line segments shown in FIG.

When a semiconductor laser having a specific resonator length is given, it is positioned as a region associated with the specific resonator length, and a lower region specified with respect to the range of the resonator length. A laser oscillation operation is performed with the light output between the upper region. Such an operation is easily realized by the power supply PS shown in FIG. The power supply PS is connected to the electrodes of the semiconductor laser, and supplies an amount of power for operating the semiconductor laser with a selected optical output. That is,
According to the present invention, the resonator length L shown in FIGS.
Is selected to operate the semiconductor laser.

Similarly, the span of the optical output Pout can be divided into the five regions shown in FIG. The values of the resonator length L in these five sections are divided by the line segments shown in FIG.

When a specific light output to the semiconductor laser is given, it is positioned as a region associated with the specific light output, and a region between the lower region and the upper region specified for the range of the light output. Is selected. The selection of the resonator length is realized by cleaving the end faces of the laser chip so as to have a desired resonator length. Thus, according to the present invention, a semiconductor laser having a cavity length corresponding to a desired optical output can be selected based on FIGS.

As described above, by examining FIG. 13, it is possible to select an optical output that operates based on a given resonator length. Meanwhile, a selection process based on FIG. 14 can be further performed. In this case, the second and third columns are examined to find one or more light output regions that include a given resonator length. From within this found area, an associated light output can be selected for a given cavity length. The above-described invention is shown in FIGS.
May be executed using one area provided by the contents shown in FIG. 13 or may be executed using a combination of two or more areas shown in FIG. 13 and FIG.

The invention described above can also be implemented in the following three preferred composite areas in FIG.
As the first composite region, about 1000 μm to about 11 μm
Semiconductor lasers having a cavity length in the region of 00 μm operate with optical powers between about 50 mW and about 100 mW. As the second composite region, from about 1200 μm to about 160 μm
A semiconductor laser having a cavity length in the region of 0 μm is about 2 μm.
It operates with optical power between 00mW and about 300mW. As the third composite region, from about 1300 μm to about 180 μm
A semiconductor laser having a cavity length in the region of 0 μm is about 3 μm.
It operates at an optical power between 50 mW and about 400 mW.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described. In the fifth embodiment, the semiconductor laser device described in the first to fourth embodiments is modularized.

FIG. 15 is a longitudinal sectional view showing a configuration of a semiconductor laser module according to Embodiment 5 of the present invention.
In FIG. 15, this semiconductor laser module 50
A semiconductor laser device 51 corresponding to the semiconductor laser devices described in the first to fourth embodiments is provided. As a housing of the semiconductor laser module 50, a Peltier device 58 as a temperature control device is disposed on an inner bottom surface of a package 59 formed of ceramic or the like. A base 57 is arranged on the Peltier element 58, and a heat sink 57a is arranged on the base 57.

The semiconductor laser device 51 is provided on the base 57.
And a heat sink 57 in which a thermistor 58a is arranged
a, the first lens 52, and the current monitor 56 are arranged. The laser light emitted from the semiconductor laser device 51 is
The light is guided onto the optical fiber 55 via the first lens 52, the isolator 53, and the second lens 54. The second lens 54 is located on the optical axis of the laser beam,
It is optically coupled to an externally connected optical fiber 55 provided above. The current monitor 56 is connected to the semiconductor laser device 5.
The light leaked from the reflective film 1 is detected by monitor.

Here, the semiconductor laser module 50
In such a case, an isolator 53 is interposed between the semiconductor laser device 51 and the optical fiber 55 so that the return light reflected by other optical components does not reenter the resonator.

FIG. 16 shows the relationship between the external temperature and the semiconductor laser device 5.
FIG. 4 is a diagram showing a relationship between the driving power of the semiconductor laser device 51 and the driving power of the Peltier element 58 when a temperature difference from the temperature of 1 is used as a parameter. The drive power supplied to the Peltier element 58 changes depending on the magnitude of the temperature difference ΔT between the external temperature of the semiconductor laser module 50 and the temperature of the semiconductor laser device 51. As shown in FIG.
As T increases, the driving power applied to the Peltier element 58 increases. For example, in order to maintain the temperature of the semiconductor laser device 51 at 25 ° C. at an external temperature of 75 ° C., the temperature difference ΔT needs to be 50 ° C. In this case, the driving power of the semiconductor laser device 51 is 1.7 W and In some cases, the driving power applied to the Peltier device 58 is 7 W.

Here, the semiconductor laser device 51 shown in the first to fourth embodiments is replaced with the semiconductor laser module 50.
Since the driving power of the semiconductor laser device 51 is reduced by applying the method described above, the driving power applied to the Peltier element 58 is also reduced. For example, temperature difference ΔT = 50 ° C.
Is maintained, and when the driving power of the semiconductor laser device 51 can be reduced from 1.7 W to 1.25 W,
The driving power applied to the Peltier element 58 is 4 W
W, which means that the power consumption of the semiconductor laser device 51 is reduced by 3 W in addition to the reduced power consumption. In this manner, by reducing the power consumption of the semiconductor laser device 51 itself, as a result, the power consumption of the entire semiconductor laser module 50 is reduced.

In the above-described fifth embodiment, the semiconductor laser module is configured to output the laser light output from the semiconductor laser device 51 as it is. However, in the vicinity of the end of the optical fiber 55 on the second lens 54 side. An optical fiber grating is formed on the optical fiber grating, and the semiconductor laser device having an optical fiber grating that selects and outputs the wavelength of the laser light output from the semiconductor laser device 51 by the optical fiber grating can be applied.

In the fifth embodiment, the first to fourth embodiments
Since the semiconductor laser device shown in (1) is modularized, in particular, the power consumed by the Peltier element 58 can be reduced, and as a result, the driving power of the semiconductor laser module 50 as a whole decreases and the optical power conversion efficiency increases. be able to.

Embodiment 6 Next, Embodiment 6 of the present invention will be described. The sixth embodiment is an example of another semiconductor laser device or another semiconductor laser module in which the efficiency of the semiconductor laser device described in the first to fourth embodiments or the semiconductor laser module described in the fifth embodiment is improved. Is shown. Embodiment 6
In the semiconductor laser device according to the third embodiment, the structure of the semiconductor laser device described in the first to fourth embodiments is further optimized, and the heat conductivity is increased by using a diamond heat sink as the heat sink 57a described in the fifth embodiment. The escape of heat from the laser device is increased.

FIG. 17 shows that the resonator length L is 1500 μm and 2 μm.
FIG. 9 is a diagram illustrating a relationship between a drive current and an optical output of a semiconductor laser device in the case of 000 μm. This semiconductor laser device has the same functional configuration as the semiconductor laser devices described in the above-described first to fourth embodiments, but is a detailed configuration of each semiconductor layer and the like, and uses a diamond heat sink as described above. ing. In this semiconductor laser device, as shown in FIG. 17, the cavity length L of 1500 μm operates with a smaller driving current until the optical output is up to 680 mW, and the cavity length L becomes 20 when the optical output exceeds 680 mW.
The operation with a drive current of 00 μm is smaller.

On the other hand, FIG. 18 shows that the resonator length L is 1500 μm.
FIG. 4 is a diagram illustrating a relationship between a light output of a semiconductor laser device and a driving power in the case of m and 2000 μm. FIG.
As shown in the figure, the resonator length L
Require the same drive power for both 1500 μm and 2000 μm, but when the optical output exceeds 180 mW, the cavity length of 2000 μm operates with less drive power, and the difference in drive power increases with the increase in optical output. Tends to increase.

Therefore, if the resonator length L corresponding to the optical output is selected from the relationship between the drive current and the optical output shown in FIG. 17, an incorrect selection is made when the resonator length L is between 180 mW and 680 mW. By selecting the resonator length L for a desired optical output based on the relationship between the optical output and the driving power shown in FIG. 18, the reactive power is suppressed, and the temperature rise of the active layer of the semiconductor laser device is suppressed. Thus, the reliability of the semiconductor laser device can be improved. In the first to fifth embodiments, the resonator length L is 1
Although it was up to 800 μm, the sixth embodiment indicates that the resonator length L can be applied up to 2000 μm. Therefore, even when the resonator length L exceeds 1800 μm and further exceeds 2000 μm, FIGS. 5 (optical power conversion efficiency with respect to resonator length) and FIG. ), FIG. 10 (driving power with respect to carrier concentration), FIG. 12 (optimum relationship with optical output with respect to resonator length), and the like. Can be optimized.

[0128]

As described above, according to the first aspect of the present invention, the resonator length of the semiconductor laser device and the carrier concentration of the upper cladding layer of the semiconductor laser device are determined with a constant optical output as a parameter. The driving power is determined based on the relationship between each element of the semiconductor laser device, including the driving power or the optical power conversion efficiency of the semiconductor laser device, and the driving power is close to the minimum or the optical power conversion corresponding to a desired optical output. By realizing a semiconductor laser device having each element value of the semiconductor laser device in which the efficiency is close to the maximum, the drive power is close to the minimum or the optical power conversion efficiency is close to the maximum.
Since a desired optical output of mW or more can be obtained, the driving power is near the minimum or the optical power conversion efficiency is near the maximum,
There is an effect that a semiconductor laser device capable of obtaining a desired optical output can be easily realized. Also,
Since the optical power conversion efficiency is close to the maximum, the reactive power is suppressed, so that the temperature rise of the active layer of the semiconductor laser device is suppressed, thereby improving the reliability of the semiconductor laser device. Play.

According to the invention of claim 2, 1000
50 mW with a constant resonator length of μm or more as a parameter
Based on the relationship between the drive power and the optical output, the resonator length at which the drive power corresponding to the desired optical output is near the minimum is determined, and the semiconductor laser device having the determined resonator length of 1000 μm or more Is realized, a desired optical output of 50 mW or more can be obtained in the vicinity of the minimum driving power, so that a semiconductor laser device capable of obtaining a desired optical output in the vicinity of the minimum driving power can be easily realized. It has the effect that it can be done. Also, since the driving power is near the minimum, the reactive power is suppressed,
The temperature rise of the active layer of the semiconductor laser device is suppressed, whereby the reliability of the semiconductor laser device can be improved.

According to the third aspect of the present invention, 50 mW
Based on the relationship between the optical power conversion efficiency and the cavity length of 1000 μm or more with the above constant optical output as a parameter,
The resonator length at which the optical power conversion efficiency corresponding to the desired optical output is near the maximum value is determined, and the determined 1000 μm
By realizing a semiconductor laser device having the above cavity length, a desired optical output of 50 mW or more can be obtained with high optical power conversion efficiency. There is an effect that a semiconductor laser device that can be obtained can be easily realized.

According to the fourth aspect of the present invention, when determining the resonator length, it is determined based on an approximate expression that maximizes the optical power conversion efficiency corresponding to the desired optical output. Therefore, it is possible to quickly determine the cavity length of the semiconductor laser device that can obtain a desired optical output with high optical power conversion efficiency by using a computer program or the like.

According to the fifth aspect of the present invention, 50 mW
The driving power for the desired light output, which is determined based on the relationship between the driving power and the cavity length of 1000 μm or more using the above constant light output as a parameter, is near the minimum 1
By realizing a semiconductor laser device having a cavity length of 000 μm or more, a desired optical output of 50 mW or more can be obtained with low driving power, so that a low optical power and a desired optical output can be obtained. There is an effect that a semiconductor laser device that can be realized can be easily realized.

According to the invention of claim 6, when the resonator length is determined, it is determined based on an approximate expression that minimizes the driving power in accordance with the desired optical output. Therefore, it is possible to quickly determine the resonator length of the semiconductor laser device that can obtain a desired optical output with a low driving power by using a computer program or the like.

According to a seventh aspect of the present invention, there is provided a semiconductor laser device having a strained multiple quantum well structure, wherein a strained multiple quantum well structure is applied as an active layer forming a resonator having the resonator length. However, since a desired optical output of 50 mW or more can be obtained with high optical power conversion efficiency or low driving power, it has a high flexibility that can be applied to semiconductor laser devices having various structures. To play.

According to the eighth aspect of the present invention, the desired light output is set in a range of 50 to 400 mW, the resonator length is set in a range of 1000 to 1600 μm, and the relationship between the drive current and the light output is set. Since a specific semiconductor laser device that can make a difference particularly when the cavity length is determined only from the above is realized, it is possible to obtain a desired optical output with high optical power conversion efficiency or low driving power. It has the effect of being able to.

According to the ninth aspect of the present invention, the desired optical output is set in the range of 50 to 200 mW, the resonator length is set in the range of 1000 to 1400 μm, and the relationship between the optical output and the drive current is adjusted. Since a specific semiconductor laser device that can make a difference particularly when the cavity length is determined only from the above is realized, it is possible to obtain a desired optical output with high optical power conversion efficiency or low driving power. It has the effect of being able to.

According to the tenth aspect of the present invention, a predetermined light output and a predetermined resonator length are used as parameters, and are determined based on the relationship between the driving power and the impurity carrier concentration of the upper cladding layer. By realizing a semiconductor laser device having the upper cladding layer in which the impurity carrier concentration is set so that the driving power is near the minimum or the optical power conversion efficiency is near the maximum corresponding to the output, the driving power is near the minimum or the light When the power conversion efficiency is near the maximum, 50
Since a desired optical output of mW or more can be obtained, the driving power is near the minimum or the optical power conversion efficiency is near the maximum,
There is an effect that a semiconductor laser device capable of obtaining a desired optical output can be easily realized.

According to the eleventh aspect of the present invention, a semiconductor laser module having the semiconductor laser device according to any one of the first to tenth aspects is realized, and a desired optical output can be converted to a high optical power conversion. Since the semiconductor laser module can be realized with high efficiency or low driving power, a desired optical output can be obtained with high optical power conversion efficiency or low driving power even in the semiconductor laser module as a whole.

According to the twelfth aspect of the present invention, an optical fiber grating is formed near the input end of the optical fiber, and a laser beam having a wavelength selected by the optical fiber grating is output. Even a semiconductor laser module that realizes a semiconductor laser device using an optical fiber grating has an effect that a desired optical output can be obtained with high optical power conversion efficiency or low driving power.

According to a thirteenth aspect of the present invention, a semiconductor laser module having the semiconductor laser device according to any one of the first to tenth aspects is realized, and a semiconductor laser module having a temperature control device mounted thereon. However, since a desired optical output can be obtained with high optical power conversion efficiency or low drive power, the semiconductor laser module as a whole can achieve desired optical output with high optical power conversion efficiency or low drive power. This has the effect that the optical output can be obtained.

According to the fourteenth aspect of the present invention, the relation acquisition step includes the step of obtaining the resonator length of the semiconductor laser device and the carrier concentration of the upper cladding layer of the semiconductor laser device using a constant optical output as a parameter. The relationship between each element of the semiconductor laser device and the drive power or optical power conversion efficiency of the semiconductor laser device is acquired, and the element value is determined based on the relationship acquired in the relationship acquisition step. Each element value of the semiconductor laser device in which the driving power is near the minimum or the light power conversion efficiency is near the maximum in accordance with the light output of Since a semiconductor laser device having an element value is formed,
With the driving power near the minimum or the optical power conversion efficiency near the maximum, it is possible to easily manufacture a semiconductor laser device capable of obtaining a desired optical output.

According to the fifteenth aspect of the present invention, the relationship obtaining step obtains the relationship between the driving power and the optical output of 50 mW or more with the constant resonator length of 1000 μm or more as a parameter. Is determined based on the relationship obtained in the relationship obtaining step, and a resonator length of 1000 μm or more at which the driving power corresponding to a desired optical output is near the minimum is determined. Since the semiconductor laser device having the cavity length determined by the length determining step is formed, it is possible to easily realize a semiconductor laser device capable of obtaining a desired optical output with a driving power near the minimum. It has the effect of being able to.

According to the sixteenth aspect of the present invention, the relationship obtaining step obtains the relationship between the optical power conversion efficiency and the cavity length of 1000 μm or more with a constant optical output of 50 mW or more as a parameter. By the decision process,
Determined based on the relationship acquired by the relationship acquisition step, determine the cavity length optical power conversion efficiency corresponding to the desired optical output is near the maximum value, by the forming step,
Since the semiconductor laser device having the resonator length determined in the resonator length determining step is formed, a semiconductor laser device having high optical power conversion efficiency and capable of obtaining a desired optical output can be easily realized. It has the effect that it can be done.

Further, according to the seventeenth aspect of the present invention, the approximate expression calculating step is a step in which the optical power conversion efficiency is maximized corresponding to the desired optical output based on the relation obtained in the relation obtaining step. Obtain an approximate expression, and the resonator length determining step determines the resonator length based on the approximate expression, so using a computer program or the like,
There is an effect that the resonator length of the semiconductor laser device that can obtain a desired optical output with high optical power conversion efficiency can be determined quickly.

According to the eighteenth aspect of the present invention, the relationship obtaining step obtains the relationship of the driving power with respect to the resonator length of 1000 μm or more using the constant light output of 50 mW or more as a parameter, and determines the resonator length. Is determined based on the relationship obtained in the relationship obtaining step, and the driving power for the desired light output becomes near the minimum.
Since the semiconductor laser device having the cavity length determined by the cavity length determining step is formed by determining the cavity length of 000 μm or more, the driving power is low, and the desired optical output is obtained. The semiconductor laser device capable of achieving the above can be easily realized.

According to the nineteenth aspect of the present invention, in the approximate expression calculating step, based on the relation obtained in the relation obtaining step, the driving power is set to correspond to the desired light output. A minimum approximate expression is obtained, and the resonator length determining step determines the resonator length based on the approximate expression.Therefore, using a computer program or the like, a desired optical output is reduced. This has the effect that the resonator length of the semiconductor laser device that can be obtained with the driving power can be determined quickly.

According to the twentieth aspect of the present invention, there is provided a semiconductor laser device having a strained multiple quantum well structure, wherein a strained multiple quantum well structure is applied as an active layer forming a resonator having the resonator length. However, since a desired optical output of 50 mW or more can be obtained with high optical power conversion efficiency or low driving power, it has a high flexibility that can be applied to semiconductor laser devices having various structures. To play.

According to the twenty-first aspect of the present invention, the relationship between the driving power and the impurity carrier concentration of the upper cladding layer is acquired by using the constant light output and the constant resonator length as parameters in the relationship acquiring step. In the concentration determining step, the impurity carrier concentration determined based on the relationship obtained in the relationship obtaining step and corresponding to a desired optical output and having a driving power near the minimum is determined. Since the semiconductor laser device in which the impurity carrier concentration of the layer is set to the impurity carrier concentration determined in the carrier concentration determining step is formed, the driving power is in the vicinity of the minimum or the optical power conversion efficiency is in the vicinity of the maximum. There is an effect that a semiconductor laser device capable of obtaining an optical output can be easily realized.

According to the twenty-first aspect of the present invention, the specific upper boundary is 50 mW for a resonator length between approximately 1000 μm and approximately 1380 μm, and approximately 1380 μm
(1 mW) * [(L−1280 μm) / 2 μ for a resonator length between 1 and 1480 μm.
m], and (1 mW) * [(L-126) for a cavity length between approximately 1480 μm and approximately 1700 μm.
0 μm) /2.2 μm] for a resonator length between approximately 1700 μm and approximately 1750 μm.
W) * [(L-1600 μm) / 1 μm],
(3 mW) * [(L-1510 μm) / 2 μ for a cavity length between approximately 1750 μm and approximately 1770 μm
m], and the specific lower boundary is approximately 1000 μm.
m and approximately 1050 μm for a resonator length of (2 m
W) * [(L−950 μm) / 1 μm], and for a resonator length between approximately 1050 μm and approximately 1200 μm, (2 mW) * [(L−750 μm) / 3 μm] For a resonator length between approximately 1200 μm and approximately 1350 μm, (2 mW) * [(L−450 μm) / 5 μm
m], and (3 mW) * [(L−150 μm) for a resonator length between approximately 1350 μm and approximately 1450 μm.
m) / 10 μm], which is approximately 1450 μm and approximately 17
The value is 390 mW with respect to the cavity length between 70 μm, and the semiconductor laser device outputs an optical output Pout that is equal to or less than a specific upper boundary and equal to or greater than a specific lower boundary based on the cavity length. Power is supplied. This makes it possible to easily realize a semiconductor laser device capable of obtaining a desired optical output when the driving power is near the minimum or the optical power conversion efficiency is near the maximum, the reactive power is suppressed, and the temperature of the active layer of the semiconductor laser device is reduced. The effect is obtained that the rise is suppressed and the reliability of the semiconductor laser device can be improved.

According to the twenty-third aspect of the present invention, the specific lower boundary is 50 mW for a resonator length between approximately 1000 μm and approximately 1380 μm, and approximately 1380 μm
(1 mW) * [(L−1280 μm) / 2 μ for a resonator length between 1 and 1480 μm.
m], and (1 mW) * [(L-126) for a cavity length between approximately 1480 μm and approximately 1700 μm.
0 μm) /2.2 μm] for a resonator length between approximately 1700 μm and approximately 1750 μm.
W) * [(L-1600 μm) / 1 μm],
(3 mW) * [(L-1510 μm) / 2 μ for a cavity length between approximately 1750 μm and approximately 1770 μm
m], and the specific lower boundary is approximately 1000 μm.
m and approximately 1050 μm for a resonator length of (2 m
W) * [(L−950 μm) / 1 μm], and for a resonator length between approximately 1050 μm and approximately 1200 μm, (2 mW) * [(L−750 μm) / 3 μm] For a resonator length between approximately 1200 μm and approximately 1350 μm, (2 mW) * [(L−450 μm) / 5 μm
m], and (3 mW) * [(L−150 μm) for a resonator length between approximately 1350 μm and approximately 1450 μm.
m) / 10 μm], which is approximately 1450 μm and approximately 17
The value is 390 mW with respect to the cavity length between 70 μm, and the semiconductor laser device outputs an optical output Pout that is equal to or less than a specific upper boundary and equal to or greater than a specific lower boundary based on the cavity length. To be selected. This makes it possible to easily realize a semiconductor laser device capable of obtaining a desired optical output when the driving power is near the minimum or the optical power conversion efficiency is near the maximum, the reactive power is suppressed, and the temperature of the active layer of the semiconductor laser device is reduced. The effect is obtained that the rise is suppressed and the reliability of the semiconductor laser device can be improved.

According to the twenty-fourth aspect of the present invention, the semiconductor laser device is operated at an optical output level Pout between about 50 mW and about 100 mW, and Is approximately 1000 μm and approximately ｛2 μm
* (Pout / 1 mW) +1280 μm}, and the semiconductor laser device can be operated optimally, so that a desired optical output can be obtained when the driving power is near the minimum or the optical power conversion efficiency is near the maximum. There is an effect that the semiconductor laser device can be easily realized.

According to the twenty-fifth aspect of the present invention, the amount of power applied to the electrodes is approximately 100 mW and approximately 200 mW.
The semiconductor laser device is operated at an optical output level Pout between the above and the cavity length is approximately ｛1 μm * (Pout / 2
mW) +950 μm} and approximately {2.2 μm * (Pout / 1
mW) +1260 μm}, and the semiconductor laser device can be operated optimally. Therefore, a semiconductor laser device capable of obtaining a desired optical output with a driving power near the minimum or a light power conversion efficiency near the maximum. There is an effect that it can be easily realized.

According to the twenty-sixth aspect, the electric power applied to the electrodes is approximately 200 mW and approximately 300 mW.
The semiconductor laser device is operated at an optical output level Pout between the above, and the cavity length is approximately ｛3 μm * (Pout / 2
mW) +750 μm and approximately {1 μm * (Pout / 2m
W) +1600 μm}, and the semiconductor laser device can be operated optimally. Therefore, a semiconductor laser device capable of obtaining a desired optical output with a driving power near a minimum or a light power conversion efficiency near a maximum. There is an effect that it can be easily realized.

According to the twenty-seventh aspect, the electric power applied to the electrodes is approximately 300 mW and approximately 360 mW.
The semiconductor laser device is operated at an optical output level Pout between the above and the resonator length is approximately ｛5 μm * (Pout / 2
mW) +450 μm｝ and approximately 1750 μm, and the semiconductor laser device can be operated optimally, so that a semiconductor device capable of obtaining a desired optical output with a driving power near a minimum or a light power conversion efficiency near a maximum. There is an effect that the laser device can be easily realized.

According to the twenty-eighth aspect of the present invention, the amount of power applied to the electrodes is approximately 360 mW and approximately 390 mW.
The semiconductor laser device is operated at an optical output level Pout between the above, and the cavity length is approximately {10 μm * (Pout /
3mW) + 150μm and approximately {2μm * (Pout / 3m
W) +1510 μm}, and the semiconductor laser device can be operated optimally, so that a semiconductor laser device capable of obtaining a desired optical output with a driving power near the minimum or a light power conversion efficiency near the maximum. There is an effect that it can be easily realized.

According to the invention of claim 29, the length of the resonator is between approximately 1000 μm and approximately 1100 μm, and the amount of power applied to the electrodes is approximately 50 mW and approximately 100 mW.
Since the light is applied to the electrode for operating the semiconductor laser device at an optical output level Pout between mW and a desired optical output when the driving power is near the minimum or the optical power conversion efficiency is near the maximum. There is an effect that a semiconductor laser device that can be easily realized can be realized.

Further, according to the invention of claim 30, the length of the resonator is between approximately 1200 μm and approximately 1600 μm, and the amount of power applied to the electrode is approximately 200 mW and approximately 30 μm.
Since the light is applied to the electrode for operating the semiconductor laser device at an optical output level Pout between 0 mW, a desired optical output is obtained when the driving power is near the minimum or the optical power conversion efficiency is near the maximum. There is an effect that a semiconductor laser device that can be easily realized can be realized.

[Brief description of the drawings]

FIG. 1 is a cutaway view of a semiconductor laser device according to a first embodiment of the present invention as viewed obliquely;

FIG. 2 is a longitudinal sectional view showing a schematic configuration of the semiconductor laser device shown in FIG. 1 in a longitudinal direction.

FIG. 3 is a sectional view taken along line AA of the semiconductor laser device shown in FIG. 2;

FIG. 4 is a diagram showing the relationship between optical power and drive power, with the cavity length as a parameter, applied to the semiconductor laser device shown in FIG. 1;

5 is a flowchart showing a method for manufacturing a semiconductor laser device formed based on the relationship shown in FIG.

6 is a diagram showing a relationship between the optical power conversion efficiency and the cavity length, which is applied to the semiconductor laser device shown in FIG. 1 and uses the optical output as a parameter.

7 is a flowchart showing a method for manufacturing a semiconductor laser device formed based on the relationship shown in FIG.

FIG. 8 is a diagram showing a relationship between the cavity length and the driving power applied to the semiconductor laser device shown in FIG. 1 and using the optical output as a parameter.

9 is a flowchart showing a method for manufacturing a semiconductor laser device formed based on the relationship shown in FIG.

10 is applied to the semiconductor laser device shown in FIG. 1,
FIG. 9 is a diagram illustrating a relationship between a driving power and a Zn carrier concentration of an upper cladding layer, using an optical output as a parameter.

11 is a flowchart showing a method for manufacturing a semiconductor laser device formed based on the relationship shown in FIG.

FIG. 12 is a diagram showing an optimal relationship between a resonator length and an optical output.

FIG. 13 is a diagram showing a relationship between an optimum optical output and a resonator length region section obtained based on FIG. 12;

FIG. 14 is a diagram showing the relationship between the optimum resonator length and the light output area division obtained based on FIG.

FIG. 15 is a diagram showing a configuration of a semiconductor laser module according to Embodiment 5 of the present invention;

FIG. 16 is a diagram showing the relationship between the driving power of the semiconductor laser device and the driving power of the Peltier element when the temperature difference between the external temperature and the semiconductor laser device temperature is used as a parameter.

FIG. 17 is a diagram illustrating a relationship between a light output and a drive current in a semiconductor laser device (L = 1500 μm, 2000 μm) according to a sixth embodiment of the present invention;

FIG. 18 is a diagram showing a relationship between a light output and a driving power in a semiconductor laser device (L = 1500 μm, 2000 μm) according to a sixth embodiment of the present invention;

FIG. 19 is a diagram showing a relationship between a drive current and an optical output using the cavity length as a parameter, which is used for determining the cavity length of the conventional semiconductor laser device.

FIG. 20 is a diagram showing a relationship between a Zn carrier concentration and a drive current with a constant optical output used as a parameter, which is used for determining a Zn carrier concentration in an upper clad layer of a conventional semiconductor laser device.

[Explanation of symbols]

 Reference Signs List 1 n-InP substrate 2 n-Inp cladding layer 3 GRIN-SCH-MQW active layer 6 p-InP cladding layer 7 p-InGaAsP cap layer 8 p-InP blocking layer 9 n-InP blocking layer 10 p-side electrode 11 n side Electrode 14 Reflection film 15 Emission-side reflection film 20, 51 Semiconductor laser device 30 Database 50 Semiconductor laser module 52 First lens 53 Isolator 54 Second lens 55 Optical fiber 56 Current monitor 57 Base 57a Heat sink 58 Peltier element 58a Thermistor 59 Package

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Toshio Kimura 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. F-term (reference) 5F073 AA22 AA45 AA74 AA83 AB27 AB28 AB30 BA09 CA12 EA24 EA29 FA02 FA06 FA25

Claims (30)

[Claims] 1. A semiconductor laser device including a resonator length and a carrier concentration of an upper cladding layer of the semiconductor laser device, and a driving power of the semiconductor laser device. Alternatively, each element value of the semiconductor laser device is determined based on the relationship with the optical power conversion efficiency, and the driving power is near the minimum or the optical power conversion efficiency is near the maximum corresponding to the desired optical output. A semiconductor laser device. 2. A driving power corresponding to a desired optical output, which is determined on the basis of a driving power relationship with respect to an optical output of 50 mW or more using a constant resonator length of 1000 μm or more as a parameter. A semiconductor laser device comprising: 3. The optical power conversion efficiency corresponding to a desired optical output is determined based on the relationship of optical power conversion efficiency with respect to a cavity length of 1000 μm or more using a constant optical output of 50 mW or more as a parameter. A semiconductor laser device having a resonator length near the semiconductor laser device. 4. The semiconductor laser according to claim 3, wherein the cavity length is determined based on an approximate expression that maximizes optical power conversion efficiency corresponding to the desired optical output. apparatus. 5. A driving power for a desired optical output, which is determined based on a relationship between a driving power for a resonator length of 1000 μm or more and a constant optical output of 50 mW or more as a parameter, is 1000 μm or more. A semiconductor laser device having a resonator length. 6. The semiconductor laser device according to claim 5, wherein the cavity length is determined based on an approximate expression that minimizes the driving power corresponding to the desired optical output. . 7. The semiconductor laser device according to claim 2, wherein the active layer forming the resonator having the resonator length has a strained multiple quantum well structure. 8. The desired light output is 50 to 400 mW.
The semiconductor laser device according to claim 2, wherein the cavity length is in a range of 1000 to 1600 μm. 9. The desired light output is 50 to 200 mW.
The semiconductor laser device according to any one of claims 2 to 7, wherein the cavity length is in a range of 1000 to 1400 µm. 10. A constant optical output and a constant resonator length are used as parameters, and are determined based on the relationship between the driving power or the optical power conversion efficiency with respect to the impurity carrier concentration of the upper cladding layer, and correspond to a desired optical output. A semiconductor laser device comprising the upper cladding layer in which the impurity carrier concentration is set such that the driving power is near the minimum or the optical power conversion efficiency is near the maximum. 11. The semiconductor laser device according to claim 1, an optical fiber for guiding a laser beam emitted from the semiconductor laser device to the outside, the semiconductor laser device and the light. A semiconductor laser module comprising: an optical coupling lens system that optically couples with a fiber. 12. The semiconductor laser module according to claim 11, further comprising a temperature control device for controlling a temperature of said semiconductor laser device, wherein an optical fiber grating is formed near an incident end of said optical fiber. 13. A temperature control device for controlling a temperature of the semiconductor laser device, and an isolator arranged in the optical coupling lens system for suppressing incidence of reflected return light from an optical fiber side. The semiconductor laser module according to claim 11, wherein: 14. Each element of the semiconductor laser device including the resonator length of the semiconductor laser device and the carrier concentration of the upper cladding layer of the semiconductor laser device, and the driving power of the semiconductor laser device, using a constant optical output as a parameter. Alternatively, a relation obtaining step of obtaining a relation with the optical power conversion efficiency, and the driving power is determined based on the relation obtained in the relation obtaining step, and the driving power is close to the minimum or the optical power corresponding to a desired light output. An element value determining step of determining each element value of the semiconductor laser device whose power conversion efficiency is close to the maximum; and a forming step of forming a semiconductor laser device having each element value determined by the element value determining step. A method for manufacturing a semiconductor laser device, comprising: 15. A relation acquisition step of acquiring a relation of drive power to an optical output of 50 mW or more with a constant resonator length of 1000 μm or more as a parameter, and the relation is determined based on the relation acquired in the relation acquisition step. A resonator length determining step of determining a resonator length of 1000 μm or more at which a driving power corresponding to a desired optical output becomes a minimum, and a semiconductor laser device having a resonator length determined by the resonator length determining step Forming a semiconductor laser device. 16. A relation obtaining step of obtaining a relation of optical power conversion efficiency with respect to a cavity length of 1000 μm or more using a constant optical output of 50 mW or more as a parameter, and a relation based on the relation obtained in the relation obtaining step. A resonator length determining step of determining a resonator length at which the optical power conversion efficiency corresponding to a desired optical output is close to a maximum value; and a semiconductor having a resonator length determined by the resonator length determining step. A method for manufacturing a semiconductor laser device, comprising: forming a laser device. 17. An approximate expression calculating step of obtaining an approximate expression that maximizes optical power conversion efficiency corresponding to the desired optical output based on the relationship obtained in the relationship obtaining step, further comprising: 17. The method according to claim 16, wherein the resonator length determining step determines the resonator length based on the approximate expression. 18. A relation obtaining step of obtaining a relation of drive power with respect to a cavity length of 1000 μm or more using a constant optical output of 50 mW or more as a parameter, and a determination based on the relation obtained in the relation obtaining step. A resonator length determining step of determining a resonator length of 1000 μm or more at which the driving power for a desired optical output is close to a minimum; and forming a semiconductor laser device having a resonator length determined by the resonator length determining step. A method of manufacturing a semiconductor laser device, comprising: 19. An approximate expression calculating step of obtaining an approximate expression that minimizes the driving power corresponding to the desired light output based on the relationship acquired in the relationship acquiring step, further comprising: 19. The method according to claim 18, wherein the resonator length determining step determines the resonator length based on the approximate expression. 20. The method of manufacturing a semiconductor laser device according to claim 14, wherein the active layer forming the resonator having the resonator length has a strained multiple quantum well structure. . 21. A relation obtaining step of obtaining a relation of the driving power to the impurity carrier concentration of the upper cladding layer using a constant optical output and a constant resonator length as parameters, and the relation obtained in the relation obtaining step. A carrier concentration determining step of determining the impurity carrier concentration, which is determined based on the driving power and corresponding to a desired optical output and is near the minimum, and the impurity carrier concentration of the upper cladding layer is determined by the carrier concentration determining step. Forming a semiconductor laser device having an impurity carrier concentration set therein. A method for manufacturing a semiconductor laser device, comprising: 22. A resonator having a front end face and a rear end face, and having a resonator length of about 900 μm to about 1800 μm, laminated in the resonator and receiving a bias potential from a power supply. An active layer connected to the two electrodes and into which current is injected, having a reflectivity of about 4% or less, a low-reflection film coated on the front end face, and having a reflectivity of about 80% or more; A high-reflection film coated on the rear end face; and an optical output connected to the electrode, the optical output being equal to or less than a specific upper boundary and equal to or greater than a specific lower boundary based on the resonator length. And a power supply for supplying an amount of power, wherein the specific upper boundary is approximately 1000 μm and approximately
50 mW for a resonator length between 380 μm,
The resonator length is L (1 mW) * [(L-128) for a resonator length between approximately 1380 μm and 1480 μm.
0 μm) / 2 μm] for a resonator length between approximately 1480 μm and approximately 1700 μm (1 mW) *
[(L-1260 μm) /2.2 μm], and (2 mW) * [(L-1600 μm) / 1 μm] for a resonator length between approximately 1700 μm and approximately 1750 μm.
And (3 mW) * [(L-1510 μm) for a resonator length between approximately 1750 μm and approximately 1770 μm.
m) / 2 μm], and the specific lower boundary is approximately 1000 μm and approximately 1050 μm.
m (2 mW) * [(L−95
0 μm) / 1 μm], which is approximately 1050 μm and approximately 1
(2 mW) * for a cavity length between 200 μm *
[(L−750 μm) / 3 μm], which is approximately 120
For resonator lengths between 0 μm and approximately 1350 μm, (2
mW) * [(L-450 μm) / 5 μm],
(3 mW) * [(L-150 μm) / 10 μm] for a resonator length between approximately 1350 μm and approximately 1450 μm, and 390 mW for a resonator length between approximately 1450 μm and approximately 1770 μm. A semiconductor laser device characterized by being a value. 23. A resonator having a front end face and a rear end face, and having a resonator length of about 900 μm to about 1800 μm; an active layer laminated in the resonator; A semiconductor laser device comprising: a low-reflection film having the following reflectance and coated on the front end face; and a high-reflection film having a reflectance of about 80% or more and coated on the rear end face. Outputs an optical output Pout that is equal to or less than a specific upper boundary and equal to or greater than a specific lower boundary based on the resonator length. The specific lower boundary is approximately 1000 μm and approximately 1380 μm.
50 mW for a resonator length between
Assuming that the resonator length is L for a resonator length between 0 μm and 1480 μm, (1 mW) * [(L−1280 μm)
/ 2 μm], from about 1480 μm to about 1700 μm.
(1 mW) * [(L-
1260 μm) /2.2 μm], which is approximately 1700 μm.
The value is (2 mW) * [(L-1600 μm) / 1 μm] for a cavity length between μm and approximately 1750 μm, and (3 mW) for a cavity length between approximately 1750 μm and approximately 1770 μm. * [(L-1510 μm) /
2 μm], and the specific lower boundary is approximately 1000 μm and approximately 1050 μm.
m (2 mW) * [(L−95
0 μm) / 1 μm], which is approximately 1050 μm and approximately 1
(2 mW) * for a cavity length between 200 μm *
[(L−750 μm) / 3 μm], which is approximately 120
For resonator lengths between 0 μm and approximately 1350 μm, (2
mW) * [(L-450 μm) / 5 μm],
(3 mW) * [(L-150 μm) / 10 μm] for a resonator length between approximately 1350 μm and approximately 1450 μm, and 390 mW for a resonator length between approximately 1450 μm and approximately 1770 μm. A semiconductor laser device characterized by being a value. 24. The amount of power applied to the electrodes is approximately 5
The semiconductor laser device is operated at an optical output level Pout between 0 mW and approximately 100 mW, and the cavity length is approximately 1
2,000 μm and approximately μ2 μm * (Pout / 1 mW) +128
24. The semiconductor laser device according to claim 22, wherein the distance is between 0 μm｝. 25. The amount of power applied to the electrode is approximately 1
The semiconductor laser device is operated at an optical output level Pout between 00 mW and approximately 200 mW, and the cavity length is approximately {1 μm * (Pout / 2 mW) +950 μm} and approximately {2.2 μm * (Pout / 1 mW). 24. The semiconductor laser device according to claim 22, wherein the value is between +1260 μm｝. 26. The amount of power applied to the electrodes is approximately 2
The semiconductor laser device is operated at an optical output level Pout between 00 mW and approximately 300 mW, and the resonator length is approximately {3 μm * (Pout / 2 mW) +750 μm} and approximately {1}
24. The semiconductor laser device according to claim 22, wherein the value is between μm * (Pout / 2 mW) +1600 μmμ. 27. The amount of power applied to the electrodes is approximately 3
The semiconductor laser device is operated at an optical output level Pout between 00 mW and approximately 360 mW, and the cavity length is approximately {5 μm * (Pout / 2 mW) +450 μm} and approximately 17
24. The semiconductor laser device according to claim 22, wherein the distance is between 50 [mu] m. 28. The electric energy applied to the electrode is approximately 3
The semiconductor laser device is operated at an optical output level Pout between 60 mW and approximately 390 mW, and the resonator length is approximately {10 μm * (Pout / 3 mW) +150 μm} and approximately {2 μm * (Pout / 3 mW) +1510 μm}. 24. The semiconductor laser device according to claim 22, wherein 29. The length of the resonator is between approximately 1000 μm and approximately 1100 μm, and the amount of power applied to the electrode is a light output level P between approximately 50 mW and approximately 100 mW.
24. The semiconductor laser device according to claim 22, wherein the voltage is applied to the electrode for operating the semiconductor laser device at out. 30. The resonator length is between approximately 1200 μm and approximately 1600 μm, and the amount of electric power applied to the electrode is set at an optical output level Pout between approximately 200 mW and approximately 300 mW. 24. The semiconductor laser device according to claim 22, wherein the voltage is applied to the electrode to be operated.