JPH0484480A - Chip carrier type composite optical element - Google Patents

Abstract

PURPOSE:To eliminate a photodiode module for monitor and miniaturize a panel and reduce the cost by constituting it such that a semiconductor laser element and a photodiode element for monitor are loaded on a metallic chip carrier, in the condition that the main light emitting face the light receiving face are opposed to each other. CONSTITUTION:This in one where a chip carrier type composite optical element 25 is mounted in an air-tight package 28 through a Peltier element 27, and window glass 29 and 30 is arranged in the laser transmitting part of this air- tight package 28. What is more, the window glass 30 has the filter function of screening the wavelength, for example, 1490nm of a semiconductor laser element 22 and transmits the wavelength, for example, 1530nm of the signal light of an optical fiber. Moreover, an optical fiber 31 for excitation, which takes in the exciting light from the semiconductor laser element 22 as the input/ output of a laser beam, and an optical fiber 32 for monitor, which irradiates a photodiode element 24 for monitor 31 with the signal light branched off from an optical fiber amplifier, are attached to constitute a semiconductor laser pump module 33.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a pumping light source for an optical fiber amplifier doped with erbium (Er3+), which is a rare earth metal, and particularly to a pumping light source using a high-output semiconductor laser element. The present invention relates to a chip carrier type composite optical device in which a semiconductor laser element of a semiconductor laser pump module and a monitoring photodiode element are mounted on a single metal chip carrier.

[Conventional technology]

Optical fiber amplifiers are attracting attention as optical amplifiers that can directly amplify optical signals without using electrical circuits. Optical fibers doped with erbium (Er'') are used as optical fiber amplifiers, but pumping light is required to amplify the signal light. Conventionally, dye lasers or solid-state lasers have been used as pumping light sources. However, in order to be commercialized as an optical communication system, it was necessary to use small semiconductor lasers.On the other hand, the requirements for semiconductor lasers were to have a specific wavelength, high output, and high reliability. However, a laser with a wavelength of around 1490 nm is considered as a semiconductor laser that satisfies this condition.

An example of a conventional optical fiber amplifier configuration is shown in FIG. In this configuration example, a wavelength combining coupler 2 is provided at the input end of the erebium-doped optical fiber 1, and the signal light from the signal semiconductor laser module 3 and the pumping light from the pumping semiconductor laser module 4 are combined to form the erebium-doped optical fiber 1. The structure is such that the amplified signal light is transmitted to the trunk cable 5. On the other hand, in order to stably output this amplified light, it is necessary to control the pumping light of the pumping semiconductor laser module 4. As an example of this control means, excitation light from the excitation semiconductor laser module 4, for example 1490
Short wavelength filter 6 and 1:10 that block wavelengths of nm or less
For example, a converter 7 having a branching ratio of about 1530n is provided.
Only the signal light of m is slightly reflected, and this reflected light is taken into the monitoring photodiode modinir 8. As a result, from the output photocurrent, the differential amplifier 9
A method has been proposed in which the excitation semiconductor laser module 4 is driven and controlled by operating an APC circuit 11 consisting of an LD current control circuit 10 and the like.

[Problem to be solved by the invention]

However, on the other hand, in response to the current demand for downsizing and cost reduction of optical communication devices, in conventional examples, the excitation light source and the monitoring receiver are separated, so the excitation semiconductor laser module 4 and one monitoring photodiode module 8 were required. That is, since the size of the monitor photodiode module 8 is usually about the same size as the excitation semiconductor laser module 4, it is necessary to secure a mounting area for 42 excitation semiconductor laser modules on the panel. This was an obstacle to downsizing. In addition, a monitor photodiode module 8
Since the number of parts and the number of assembly steps are almost the same as those of the excitation semiconductor laser module 4, an increase in cost has also been a problem.

Therefore, in order to solve this problem, it would be sufficient to integrate the excitation semiconductor laser module 4 and the monitoring photodiode module 8. A conventional semiconductor laser module with a built-in monitor photodiode element monitors the monitor light of the semiconductor laser element and controls the drive of the semiconductor laser element, which is essentially different from the method of an optical fiber amplifier system, and is different from the conventional method. It was not possible to use the semiconductor laser module as is.

For example, there is a chip carrier type composite optical device as shown in FIGS. 6 to 8 (a) to (d) as an assembly structure of a monitor photodiode element and a semiconductor laser element incorporated in a conventional semiconductor laser module. Ta. This includes a metal chip carrier type semiconductor laser element 12 and a ceramic chip carrier type monitoring photodiode element 13.
It is mounted on two metal bases 14 with solder, etc.
These devices were generally called a chip carrier type LD device. However, in this text, in order to distinguish it from the conventional example, it will be referred to as a chip carrier type composite optical device 15 hereinafter. As is clear from the figure, the conventional monitor photodiode element 1
Reference numeral 3 receives monitor light from the semiconductor laser element 12 and controls the semiconductor laser element 12. However, in the case of an optical fiber amplifier, rather than receiving its own semiconductor laser light, for example, 1490 nm excitation light, it receives laser light from another semiconductor laser (in this case, 1530 nm signal light), and the same module The semiconductor laser inside (
In this case, the conventional chip carrier type composite optical device 15 could not be used because the device controls the driving of excitation light.

Therefore, it is an object of the present invention to provide a chip carrier type composite optical device that can integrate a separate pumping semiconductor laser module and a monitoring semiconductor laser module into one semiconductor laser pump module. .

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a chip carrier type composite optical device in which a semiconductor laser element and a monitoring photodiode element are mounted on one metal chip carrier. The main light emitting surface of the semiconductor laser element and the light receiving surface of the monitoring photodiode element are mounted on the metal chip carrier with their faces facing in opposite directions.

[Effect]

In this way, by using the chip carrier type composite optical device of the present invention, the conventional monitor photodiode module can be removed and integrated into one semiconductor laser pump module, resulting in a smaller panel and lower cost. It can be expected to make a significant contribution to the commercialization of optical fiber amplifier systems.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of a chip carrier type composite optical device according to the present invention. In this embodiment, the chip carrier of the conventional metal chip carrier type semiconductor laser element 12 and the conventional metal base 14 are used as one metal chip carrier 20.
The semiconductor laser device 2 is placed on the semiconductor laser device loading section 21 of 0.
2 is loaded with solder, etc. Furthermore, a ceramic chip carrier-type monitor photodiode element 24 is similarly mounted on the photodiode loading portion 23 of the metal chip carrier 20 on which the conventional ceramic chip carrier-type monitor photodiode element 13 is mounted, using solder or the like. A type composite optical element 25 is constructed.

However, the laser light-receiving surface 24a of the monitoring photodiode element 24 is stacked in such a manner that it faces in the opposite direction to the main light-emitting surface of the semiconductor laser element 22, that is, the signal light emission direction A, which is different from the conventional assembly structure. They have different configurations. Further, a ceramic chip carrier type monitoring photodiode element 24 is loaded on a ceramic chip carrier 26, and is loaded on the photodiode loading portion 23 of the metal chip carrier 20 via this ceramic chip carrier 26.

By using the chip carrier type composite optical device 25 of the present invention configured as described above, it is possible to integrate the excitation semiconductor laser module and the monitoring photodiode module, which were previously separate, into one. It has become possible to realize a semiconductor laser pump module. An example of this is now shown in FIG. FIG. 2 shows a chip carrier type composite optical device 25 mounted in an airtight package 28 via a Peltier element 27.
Window glasses 29 and 30 are disposed in the laser beam transmitting section 8. Note that the window glass 30 has a semiconductor laser element 220
It has a filter function of blocking a wavelength of, for example, 14907 nm and transmitting signal light of an optical fiber amplifier, for example, a wavelength of 1530 nm. Additionally, a pumping optical fiber 31 that takes in pumping light from the semiconductor laser element 22 as input and output of laser light and a monitoring optical fiber 32 that irradiates the monitoring photodiode element 24 with signal light branched from the optical fiber amplifier are attached. This constitutes the semiconductor laser pump module 33. Note that the size of this semiconductor laser pump module 33 can be designed to be approximately the same size as the conventional excitation semiconductor laser module, and can be easily realized.

Further, an application example of a semiconductor laser amplifier module realized using the chip carrier type composite optical device 25 of the present invention is shown in FIGS. 3 and 4. Elebium doped optical fiber 3
It is only necessary to guide the branched light from the coupler 35 or the fusion coupler 36 of No. 4 to the monitor photodiode element 33a of the semiconductor laser pump module 33 through the monitor optical fiber 37, which replaces the monitor photodiode module used in the conventional configuration example. can be deleted. Note that the monitoring optical fiber 37 is a normal single mode fiber or multimode fiber. Also, reference numeral 38 in the figure
3 is a signal semiconductor laser module, 39 is a wavelength combining coupler, 40 is a trunk optical cable, and furthermore, APC circuits and the like are omitted.

〔Effect of the invention〕

As described above, by using the chip carrier type composite optical device of the present invention, the conventional monitoring photodiode module can be omitted and can be integrated into one semiconductor laser pump module. This brings about various excellent effects, such as making it possible to reduce the size and cost of the panel and also expecting a great contribution to the commercialization of optical fiber amplifier systems.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of a chip carrier type composite optical device according to the present invention, and Fig. 2 shows a semiconductor laser pump module assembled using the chip carrier type composite optical device of the present invention. Cross-sectional view of the module structure, Figures 3 and 4
The figure is a schematic diagram of an optical fiber amplifier system showing an application example of this semiconductor laser pump module, Figure 5 is a schematic diagram of a conventional optical fiber amplifier system, and Figure 6 is an example of a conventional chip carrier type composite optical element. A perspective view showing
FIGS. 7(a) and 7(b) are a plan view and a front view of a conventional metal chip carrier type semiconductor laser device, and ff8(a) to FIG.
(d) is a plan view, a front view, a side view, and a bottom view of a conventional ceramic chip carrier type monitoring photodiode element. 20...Metal chip carrier, 2...
・Semiconductor laser element, 4...Monitoring photodiode element, 4a...
... Laser receiving surface, 5 ... Chip carrier type composite optical element, 6 ...
...Ceramic chip carrier. Applicant Attorney: NEC Co., Ltd.

Claims (1)

[Scope of Claims] 1. In a chip carrier type composite optical device in which a semiconductor laser element and a monitoring photodiode element are mounted on a single metal chip carrier, the main light emitting surface of the semiconductor laser element and the monitoring photodiode element are mounted on a single metal chip carrier. A chip carrier type composite optical device, characterized in that the light-receiving surfaces of the devices are mounted on the metal chip carrier with their light-receiving surfaces facing in opposite directions. 2. The chip carrier type composite optical device according to claim 1, wherein the monitoring photodiode element is mounted on a ceramic chip carrier, and the monitoring photodiode element is mounted on the metal chip carrier via the ceramic chip carrier.