KR101985016B1 - Optical Device Capable of Fine Tuning of Output Power And Manufacturing Method Thereof - Google Patents

Abstract

The present invention relates to an optical device including a laser diode, the laser diode for outputting light having a predetermined wavelength; An optical output unit to which the output light of the laser diode is optically coupled to output the optical device; And an optical isolator positioned between the laser diode and the optical output unit, wherein the output light of the laser diode is passed through the optical isolator to be output of the optical element through the optical output unit, and is rotated by the optical isolator. Characterized in that the intensity of the output light of the optical device is determined.

Description

Optical Device Capable of Fine Tuning of Output Power And Manufacturing Method Thereof}

The present invention relates to an optical device capable of precisely adjusting the intensity of the light output and a method of manufacturing the optical device.

The contents described in this section merely provide background information on the embodiments of the present invention and do not constitute a prior art.

Recently, the communication method, which is being standardized under the name NG-PON2, adopts a time wavelength division multiplexing (TWDM) method. In the TWDM method, a plurality of subscribers simultaneously connected to one optical fiber may arbitrarily select any one of four or eight allowed wavelength channels, and a plurality of subscribers using the same wavelength channel may have a time only at a predetermined time. It is a method of sharing optical fiber by TDM (time division multiplexing) method.

The communication standard of NG-PON2 is specified as the optical power ratio (ER: extinction ratio) of the "1" signal and "0" signal of the optical element as 6, and the optical power is specified as 4 ~ 9dBm. It is also possible that the ER can have a different value, in which case it is required to offset the change in the ER with light output.

In general, when the ER of the optical transmitter is lowered, the light reception sensitivity becomes worse. Accordingly, when the ER is lowered, the intensity of the output light should be increased. If the ER is 4.7dB instead of 6dB, the light output should be about 6.7dBm ~ 9dBm to remove the effect on the light reception sensitivity.

The optical power intensity allowed by NG-PON2 should be satisfied in all temperature and all operating conditions. In general, in the optical sub-assembly (OSA) structure in which an optical element is combined with an optical fiber, many instruments are combined. Although the intensity of light output from the semiconductor laser diode is increased by thermal expansion and contraction due to temperature change, the ratio of optical coupling with the optical fiber is changed according to the external temperature change, so that the optical intensity coupled with the optical fiber is changed.

Regardless of the light output emitted from the laser diode chip of the optical transmitter, the change of the light output according to the external environmental temperature is called a tracking error. In general, the tracking error is +/- 1 dB or +/- for a well-managed optical device. It is estimated to be about 0.5dB. In the NG-PON2, the light output of 6.7dBm ~ 9dBm refers to the range of optical power coupled to the optical fiber, which must be satisfied in any environment. Therefore, considering the tracking error +/- 1dB or +/- 0.5dB, OSA type The optical power of the fabricated optical device is about 7.7dBm ~ 8.0dBm or 7.2dBm ~ 8.5dBm. In the case of optical fiber coupling to OSA, the power loss is generally estimated to be +/- 0.3dB. In this case, considering the tracking error of +/- 0.5dB and the optical fiber coupling error of +/- 0.3dB, the optical power intensity in OSA fabrication is It should be about 7.5dBm ~ 8.2dBm. In other words, the intensity of the light output is less than 1dB setting range, there is a lot of problems in the yield of the production process.

Optical device OSA manufacturing is mainly produced using a laser welding process, the light coupling efficiency of this process is made of about 40 ~ 70%, it is very difficult to control the laser welding process by controlling the coupling efficiency very constant. The reason is that the core diameter of the optical fiber is very small as 8um, and in the case of laser welding, twisting occurs while metal components are melted, combined, and cooled again by a high-power laser, and the twisting occurs irregularly.

In the laser welding process, the optical coupling efficiency of 40 to 70% means that the optical coupling efficiency occurs irregularly in the range of -1.5 dB to -4 dB, and the variation of the optical coupling efficiency during the laser welding reaches up to 2.5 dB. do. This change in optical coupling efficiency causes a change in the intensity of output light of the optical device to be produced.

Add the irregularity of optical coupling efficiency in the laser welding process up to 2.5dB, tracking error maximum width 2dB (+/- 1dB), and irregular optical coupling loss 0.6dB (+/- 0.3dB) when coupling optical fiber to OSA. In general, the range of intensity of light output that can be obtained reaches up to 5 dB. Reflecting these points, in the international standard of NG-PON2, the light output condition of transmitting OSA is defined as + 4dBm to + 9dBm.

However, in order to apply a laser diode, especially DFB-LD as a light source of NG-PON2, when the DFB-LD is driven at 6, the deterioration of transmission characteristics due to chirp, which is an inherent characteristic of DFB-LD, becomes a problem. When the ER is reduced to about 4.7 to prevent the transmission quality degradation caused by the chrip, the reception sensitivity is decreased at the receiver, and the optical power intensity of the OSA must be increased to compensate for the degradation of the reception sensitivity at the receiver by the low ER. However, when the OSA's light output intensity rises above + 9dBm, it produces various side effects such as four wave mixing and other optical signals using the same fiber at the same time, so the maximum output combined with the optical fiber in OSA satisfies + 9dBm. shall.

Therefore, when using ER lower than ER 6 in NG-PON2, only the lowest value of optical power should be raised and the highest value should be maintained. For this reason, in case of optical communication using optical signal of ER 4.7, the OSA optical power intensity of optical transmitter should be maintained at 6.7dBm ~ + 9dBm to compensate for the decrease in reception sensitivity at optical receiver. The light output range of 6.7dBm ~ 9dBm is 2.3dB and this narrow light output range considers the error width 0.6dB when combining OSA and optical fiber and the tracking error 1dB (+/- 0.5dB). It is concluded that the optical coupling efficiency range of the coupling process should be within 0.7 dB. Precise control of the light coupling efficiency when laser welding within 0.7 dB is a very difficult process.

In communication methods other than NG-PON2, there is no big limitation on the range of current injected into the laser diode. In general, the current flowing to the laser diode chip when the intensity of light output is lower than the target under normal laser diode driving conditions after the coupling process. Increase the light output intensity itself in the laser diode chip to meet the optical output target range.If the OSA optical output is larger than the target range under normal laser diode driving conditions, reduce the current flowing to the laser diode chip to reduce the OSA optical output. Make it within a certain range.

However, in the case of NG-PON2 using DFB-LD, the current flowing through the laser diode chip is low, so it is difficult to cope with the high-speed signal of 10Gbps when the light output is low, and the laser diode chip when the current intensity to the laser diode chip increases. In response to heat generation of the thermoelectric element used to maintain the light source at a constant wavelength is difficult to give excessive heat. For this reason, the DFB-LD used as the light source of the NG-PON2 allows only a very narrow current range, and unlike other optical communication devices, the current flowing to the DFB-LD cannot be significantly changed. Therefore, in case of using DFB-LD in NG-PON2 method, the optical coupling efficiency in the coupling process should be controlled in a very narrow range, and laser welding, etc. should be considered in consideration of various changes that may occur in optical devices. The optical coupling efficiency of the coupling process should be adjusted to have the optical coupling efficiency to be 0.7 dB or less. This bonding process causes the manufacturing process to increase the complexity or the time required, and furthermore, it is the biggest cause that adversely affects the production yield. In particular, using laser welding causes more and more problems.

The present invention provides an optical device capable of compensating for an irregular error in optical coupling efficiency caused by the coupling process when a range of intensity of light output is determined, and allowing the intensity of light output to fit within a predetermined range, and a method of manufacturing the same. There is one purpose.

It is also an object of the present invention to provide an optical device capable of precisely adjusting the intensity of light output and a method of manufacturing the same.

It is also an object of the present invention to provide an optical device and a method for manufacturing the same, which accurately adjust the intensity of the light output and maintain the light output in a predetermined range of intensity.

As a means for solving the problems of the present invention, an optical device including an embodiment of a laser diode includes a laser diode for outputting light having a predetermined wavelength; An optical output unit to which the output light of the laser diode is optically coupled to output the optical device; And an optical isolator positioned between the laser diode and the optical output unit, wherein the output light of the laser diode is passed through the optical isolator to be output of the optical element through the optical output unit, and is rotated by the optical isolator. Characterized in that the intensity of the output light of the optical device is determined.

In one embodiment, the optical device further comprises a rotating plate portion, the optical isolator is coupled to one surface of the rotating plate portion, characterized in that the optical isolator is rotated by the rotation of the rotating plate portion.

In one embodiment, the optical device includes a first housing, a second housing, the first housing is coupled to the laser diode, the second housing is coupled to the optical output, the first housing And the second housing are combined, a cavity having a predetermined space is formed on a path where the output light of the laser diode proceeds to the optical output part; The optical isolator is located in the cavity.

In one embodiment, it further comprises a third housing between the first housing and the second housing.

In one embodiment, one side of one of the first to third housings is characterized in that it further comprises a through-hole that can be located protruding from the rotating plate portion.

In one embodiment, after combining the first housing and the second housing by the first coupling means, by rotating the rotating plate portion to set the output light of the optical device to a predetermined intensity, the rotating plate portion by the second coupling means It is characterized in that the fixing.

In one embodiment, the first coupling means is any one of laser welding, electrical welding, polymer compound adhesive, the second coupling means is characterized in that any one of laser welding, electrical welding, polymer compound adhesive.

According to another aspect of the present invention, there is provided a method of manufacturing an optical device including a laser diode, the method comprising: coupling a laser diode to a first housing; Coupling the light output to the second housing; Positioning a rotatable optical isolator between the first and second housings, and coupling the first and second housings; Rotating the optical isolator to set the intensity of output light of the optical element; And fixing the optical isolator when the intensity of the output light reaches a predetermined intensity.

The present invention has the advantage of producing an optical device having a desired light output by mechanically adjusting the intensity of the light output according to the change in the optical coupling efficiency generated in the production process, rather than the current control.

In addition, it is possible to compensate for errors occurring in the production process, the burden of the production process is reduced, the production time is shortened, there is an advantage that the yield is high.

In addition, since the mechanical adjustment is possible, it can be applied to various standards, and at the same time has the advantage that can be applied to various forms.

1 is a cross-sectional view of one embodiment of the TOSA
Fig. 2 Operation principle of the optical isolator
Fig. 3 Insertion loss according to the angle of incident light of the optical isolator
4 and 5 are cross-sectional views of one embodiment of the TOSA proposed in the present invention.
Figure 6 is a top view of the TOSA proposed in the present invention
Figure 7 Cross-sectional view of one embodiment of the BOSA
8 is a cross-sectional view of an embodiment of the BOSA proposed in the present invention

As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing the drawings, similar reference numerals are used for similar elements.

Terms such as first, second, A, and B may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. It is to be understood that the term "comprises" or "having" in the present application does not exclude in advance the possibility of the presence or addition of features, numbers, steps, operations, components, parts or combinations thereof described in the specification. .

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art.

Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the optical device and the optical device manufacturing method capable of precise light output intensity control according to the present invention.

1 is a side cross-sectional view of a transmitter optical subassembly (TOSA) including a TO-CAN type laser diode, which is a type of optical device.

In the optical communication, since the laser diode is disturbed by the laser light 16 incident to the laser from the optical fiber 13 side, the laser light 16 from the laser diode 15 to the optical fiber 13 is transmitted, and the laser diode from the optical fiber side. An optical isolator 14 may be used to block laser light directed to the chip. Since the optical fiber 13 is made of glass, it is not easy to combine with other components.

1 is an optical fiber receptacle and TO-can type in which a second housing 18 of stainless steel (SUS) is held by a zirconia-based ferrule holding the optical fiber 13 and the optical fiber 13 that are made of glass. The shape of TOSA which is a light coupling optical element with the laser diode 15 is shown. The optical fiber has a core diameter of 8 μm, so that the light emitted from the TO-can laser diode package must be precisely positioned to achieve an effective optical coupling. The present invention is not limited to the configuration of the output terminal to the optical fiber, it can be substituted according to the application field in various forms such as a lens.

TOSA comprises a first housing 17 for coupling a TO-can type laser diode, a second housing 18 including an optical fiber, and a third housing 19 for coupling the first housing 17 and the second housing 18. ). The third housing 19 may be integrally formed with the first housing 17 or the second housing 18, and may be separately formed. In addition, it is possible to configure not only three housings but also two, and a larger number of housings. This embodiment has a structure in which the three housings are separated and coupled to each other.

The manufacture of TOSA combines the TO-can type laser diode 15 with the first housing 17 made of stainless steel, and between the first housing 17 and the second housing 18. After inserting the isolator 14, the first to third housings 17, 18, and 19 holding the TO-can are engaged. Coupling may be combined using an adhesive such as laser welding, electrical welding, epoxy, etc. In the present embodiment, the welding spot 15 is bonded using laser welding.

When laser welding the first to third housings, the metals of the first to third housings are melted and then combined and cooled, so that the optical elements are combined into one. In this process, the relative positions of the TO-can laser diode 15 and the optical fiber 13, which were initially precisely aligned, are distorted after the metal is melted, bonded, and then solidified again. If the relative position is misaligned, the light path 16 is changed to change the intensity of the final light output of the optical fiber 13. That is, the optical coupling efficiency is changed. The degree to which the relative position is distorted is usually unpredictable, so precise control of the final light output output to the optical fiber 13 is difficult. That is, the error of optical coupling efficiency generated during the coupling process is almost impossible to reduce unless the optical power intensity is coupled in real time.

In particular, when the width of the control of the driving current of the laser diode chip is limited due to characteristics such as high speed communication of the laser diode chip of the aforementioned application field, it is very important to adjust the light output output from the TOSA to a very narrow area. It's a difficult way.

2 is a diagram illustrating an operation of the optical isolator 14. The optical isolator consists of a Faraday rotator that changes the polarization of the laser light by 45 degrees and two polarizers that cross the direction of the transmitted polarization at a 45 degree angle. In the optical isolator in the direction of the laser light transmission, the polarization of the light transmitted through the first polarizer is rotated 45 degrees in the Faraday rotator to have the polarization in the direction of transmission through the second polarizer. Thus, the light is transmitted through the optical isolator. Will be. Lasers entering the direction of light blocking in the optical isolator are typically polarized, and only the components passing through the first polarizer pass through the polarizer. The light transmitted through the first polarizer has a polarization direction orthogonal to the second polarizer in the Faraday rotator. Accordingly, light of the polarized light passing through the first polarizer is also blocked by the second polarizer, thereby blocking the light. In the case of the light traveling in the optical isolator in the direction of light transmission, insertion loss in the first polarizer is generated depending on the polarization of the laser light and the polarization direction of the first polarizer.

Therefore, the conventional optical isolator is marked on the polarizing plate in the direction of light transmission to indicate the polarization direction of the polarizing plate, and the manufacturer of the TOSA using the optical isolator to improve the efficiency, the polarization direction of the optical isolator and the laser diode TOSA is manufactured by matching the polarization direction of the laser light emitted from the chip.

3 shows the insertion loss generated in the optical isolator in decibels (dB) according to the relative angle between the polarization direction of the laser light and the polarization direction of the optical isolator with respect to the laser light traveling in the direction passing through the optical isolator 14. This picture is measured in units. Even in the case of laser light propagating in the direction of light transmission, the insertion loss of the optical isolator changes according to the relative angle of the polarization direction of the laser light and the direction of the optical isolator, and the insertion loss may occur from 0 dB to 30 dB or more. Can be.

4 and 5 is a structure of the TOSA which is an embodiment of the optical device proposed in the present invention.

The TOSA includes a first housing 110 coupled to the TO-CAN type laser diode 100, a second housing 150 including the optical fiber 170, and a third housing 140 coupled to the second housing 150. And a rotating plate part 120 positioned between the third housing 140 and the first housing 110, and an optical isolator 130 positioned on one surface of the rotating plate part 120.

As shown in FIG. 4, the TO-can type laser diode 100 including the laser diode chip is laser-welded to the first housing 110 and the second housing 120 and the third housing 140 are assembled in the TOSA assembly process. By laser welding, a plurality of housings are primarily joined. As mentioned above, the number of housings may include a housing to which a laser diode is coupled and a housing to which an output unit is coupled, such as an optical fiber to which output light is output, and the number is not important. Laser welding is possible with the various joining methods mentioned above.

After the laser welding, the cavity 190 existing in a path passing by the light of the laser diode of the first housing 110 between the first housing 110 and the third housing 140 to be coupled to the optical fiber 170. After positioning the rotating plate 120 including the optical isolator 130, laser welding is performed at a predetermined point.

The rotating plate part 120 including the optical isolator 130 may include a first housing 110 and a third housing (inserted into the cavity 190 between the first housing 110 and the third housing 140). 140 may be arranged to be sandwiched between the assembled form. However, the permanent fixing such as laser welding is not applied to the rotating plate 120, and the rotating plate 120 is rotated in a state in which the first housing 110 and the third housing 140 are laser welded or the like. Make this possible.

The rotating plate part 120 has one surface of the first housing 110 and / or the third housing 140 in order to facilitate rotation in a state where the first housing 110 and the third housing 140 are laser welded or the like. A guide portion (not shown) for guiding the rotation of the rotating plate 120 may be further included. When the shape of the portion where the rotating plate portion 120 is located in the first housing 110 and in contact with the first housing 110 and the rotating plate portion 120 has a circular shape, the guide portion has a circular shape with a larger area than the circular shape. It would be desirable to do this. The rotating plate part 120 and the guide part may be configured in various shapes, and may be formed like a cog wheel to check the angle of rotation.

At least one side of the third housing 140 may include a through-hole 141 for rotating the rotating plate 120. The rotating plate 120 may be partially exposed to rotate the through hole 141.

The optical isolator 130 is coupled to one surface of the rotating plate 120, the combined surface may form a hole so that the output of the laser diode 100 can pass through the optical isolator 130.

 In the optical module assembled in the above state, the relative position of the TO-can type laser 100 and the optical fiber 170 is fixed by pre-laser welding, but the optical isolator 130 is rotated by the rotating plate part 120. It is possible. Therefore, deformation such as shrinkage after laser welding, which occurs in laser welding, is determined at the end of laser welding of the optical module, and does not change any more after time passes.

In the optical module manufactured as described above, the desired current flows to the laser diode to make the light output. If the light intensity output through the optical fiber is different from the desired light intensity, the rotating plate part 120 is rotated to rotate the optical isolator. Adjust the angle of the optical isolator so that the light intensity output through the predetermined light intensity. Thereafter, the rotating plate part 120 including the optical isolator 130 is fixed to the first housing and / or the third housing with an epoxy or the like to finally fix the angle of the optical isolator. The angle of the optical isolator means the angle on the X-Y plane that rotates about the Z axis.

The rotation of the rotating plate 120 is preferable to rotate about the Z axis on the X-Y plane because the internal structure (cavity) of the optical element is very narrow. However, the rotation of the rotating plate 120 includes a vector that rotates about the Z axis on the X-Y plane. That is, the rotation of the optical isolator 130 of the rotating plate 120 is characterized by rotating around the optical axis of the light incident on the optical isolator 130, in other words, the light is incident on the optical isolator 130 It characterized in that the rotating plate 120 is rotated on the surface and the horizontal plane.

By using the optical module and the manufacturing method proposed in the present invention, it is possible to compensate for the change in the light output caused after laser welding, and the precise output is controlled by such compensation, so that various systems requiring precise output are required. The advantage is that it can meet the output requirements. In addition, after the production, the effect of the product yield is dramatically increased by the correction by the rotation of the rotating plate 120 can be obtained at the same time. In addition, since the optical coupling efficiency is not precisely controlled during laser welding, the time for producing one optical module is shortened. Although it includes the step of adjusting the rotating plate portion 120 while looking at the output of the laser, because the output is confirmed in the step of confirming the quality of the laser produced before, the additional process in the present invention has been precisely laser workers This can save time rather than welding.

FIG. 6 is a view along the Z axis of the embodiment of FIG. 5. Rotating plate 120 is an embodiment of the one side in the through-hole 141, the rotating plate 120 is to rotate on the X-Y plane. Rotation may be clockwise or counterclockwise, and the light output changes as the rotation is performed. In addition, although the laser melting point 180 welds three points in this embodiment, the welding point does not matter if the rotation plate 120 does not affect the rotation.

The embodiment of the present invention implements the technical idea of the present invention by using the rotation of the optical isolator, but may include an optical device that implements a similar function including a polarizer and a Faraday rotator in addition to the optical isolator in an equal range.

In addition, the light output from the laser diode may be parallel light, and after passing through the optical isolator, it may be concentrated and output through the lens to the light output unit.

In addition, although the embodiment has been described based on the TOSA structure including only the laser diode, in addition to the laser diode, it may include an additional optical device such as a photodiode. As an example of such a configuration, a BOSA structure as an embodiment will be described.

The present invention is particularly effective in applications to communication standards such as NG-PON2 where the intensity of light output should be controlled in a very narrow area. In NG-PON2, the upward light wavelength is 1532 nm band and the downward light wavelength is 1596 nm band. . The present invention can simultaneously transmit and receive an optical signal with one optical module in the communication of the NG-PON2, Figure 7 shows an embodiment of a conventional bidirectional optical module for NG-PON2.

In this description, the optical transmitter is described as a TO-can transmitter in a bidirectional optical sub assembly (BOSA), and the optical receiver is illustrated as a TO-can optical receiver, but the transmitter is a mini-flat package. Alternatively, a butterfly package may be used. In addition, in FIG. 7, the laser light output from the transmitter as parallel light is transmitted through the optical isolator and the 45 degree beam splitter to the optical fiber through the lens, and the signal transmitted from the system not shown in the figure through the optical fiber is in front of the optical fiber. Although converted to parallel light through the lens, it is represented as being reflected by the 45 degree beam splitter to enter the optical receiver to receive the optical signal, but there is no problem in the application of the present invention even if the parallel light is replaced with convergent light or divergent light.

Conventionally, a transmitter and a 45 are transmitted to a laser diode chip to remove an optical signal transmitted through a 45 degree beam splitter (240) in a signal transmitted to a BOSA for bidirectional communication through an optical fiber from an external system not shown in the drawing. The optical isolator 220 is inserted between the beam splitters, but the optical isolator 220 is fixed to the SUS portion 211 connected to the transmitter or the optical isolator is fixed to the BOSA body (230, a business card called 'BOSA body portion'). After attaching, the SUS and the SUS of the BOSA body including the transmitter were integrally fixed by laser welding. Therefore, in the conventional method, since the optical isolator is fixedly attached to the BOSA body or the transmitter part, the rotation of the additional optical isolator is impossible. In the conventional method, after fixing the transmitter and the BOSA body by laser welding, the SUS part including the optical fiber is optically aligned with the laser of the transmitter, and then the SUS containing the optical fiber is welded by the BOSA body and the laser welding method. Therefore, in the conventional optical module fabrication method, as described in FIG. 1, it is difficult to prevent a change in light coupling efficiency due to shrinkage after laser welding, and thus it is difficult to constantly adjust the light intensity output through the optical fiber for a predetermined laser diode driving power. .

8 is an embodiment of the present invention for solving this problem.

In FIG. 8, as shown in FIG. 5, the optical isolator 220 is coupled on the rotatable plate 300 to be rotated, and is assembled in the form inserted between the SUS of the transmitter 210 and the SUS of the BOSA, and then the SUS and BOSA of the transmitter. SUS of the body is combined and fixed by the method of laser welding. The rotating plate part 300 to which the optical isolator 220 is attached is included between the SUS portion 211 of the transmitter and the SUS 231 of the BOSA body, and is rotatable because it is not fixed by laser welding or the like. After the transmitter 210 and the BOSA body 230 are combined and fixed by laser welding, the SUS including the optical fiber is aligned with the laser of the transmitter and then includes the SUS 231 and the optical fiber of the BOSA body again. The SUS 261 is fixed by a method such as laser welding. After the SUS 261 including the optical fiber is laser welded, the optical coupling efficiency at the time of optical alignment of the SUS 261 including the optical fiber may be significantly different. However, the change in the light coupling efficiency after the laser welding can easily adjust the intensity of the light output by rotating the rotating plate 300 is attached to the rotatable optical isolator 220.

After the optical coupling efficiency of the laser diode chip and the optical fiber is precisely controlled through the rotation of the optical isolator 220, the rotating plate 300 having the optical isolator is attached to the SUS 2110 including the transmitter or the SUS of the BOSA body. 231) and epoxy or bond to prevent unwanted rotation of the isolator due to vibration.

In the description of the present invention, the method of laser welding is used when combining the SUS portion (housing) and the SUS portion (housing), which is only one embodiment, and various methods, for example, electrical welding and adhesives such as epoxy. By combining, etc. can be applied.

Components and technical features of the embodiments of the present invention can be shared with each other, which may be applied by substitution or addition.

Although the present invention has been described by specific embodiments such as specific components and the like, but the embodiments and the drawings are provided to assist in a more general understanding of the present invention, the present invention is not limited to the above embodiments. For those skilled in the art, various modifications and variations can be made from these descriptions.

Therefore, the spirit of the present invention should not be limited to the above-described embodiments, and all of the equivalents or equivalents of the claims, as well as the following claims, fall within the scope of the spirit of the present invention. will be.

10, 100 laser diodes
110 First Housing
120, 300 rotating plate
130 optical isolator
140 Third Housing
141 through air
150 Second Housing
160 ferrules
170 fiber optic
180 laser welding spot
190 Joint
210 Transmitter, Optical Transmitter
220 light isolator

Claims (12)

In the optical device comprising a laser diode,
A laser diode for outputting light having a predetermined wavelength;
A first housing coupled to the laser diode;
A third housing coupled to the first housing and including a through portion at one side thereof;
A cavity disposed between the first housing and the third housing in a path through which the light output from the laser diode passes;
Located in the cavity, and comprises a rotating plate including an optical isolator rotatably coupled in a form sandwiched between the first housing and the third housing,
The first housing and the third housing are coupled through laser welding,
The rotating plate portion is partially exposed to the outside of the third housing through the through hole to enable rotation after the laser welding,
The rotating plate portion,
And when a predetermined current is applied to the laser diode after laser welding, the output light is rotated to have a predetermined intensity and then fixed to the first housing and / or the third housing. The method of claim 1,
And a second housing coupled to the third housing. The method of claim 1,
The rotating plate portion is an optical device, characterized in that fixed with a polymer compound adhesive. The method of claim 1,
One surface of the first housing and / or the third housing is an optical element, characterized in that it further comprises a guide for guiding the rotation of the rotating plate portion. The method of claim 1,
The shape of the portion in which the rotating plate portion is in contact with the first housing and / or the third housing is a circular shape. The method of claim 1,
The optical device is a bidirectional optical sub assembly (BOSA) optical transmission and reception device,
Further comprising a BOSA body portion coupled to the third housing,
The BOSA body portion, characterized in that it comprises a beam splitter. delete delete delete delete delete delete

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