JP6898245B2 - Optical bench subassembly with integrated optical device - Google Patents

Description

Cross-reference with related application

This application is
(1) Priority is claimed based on US Provisional Patent Application No. 62/136601 filed on March 22, 2015.
(2) A partial continuation of U.S. Patent Application No. 13/861273 filed on April 11, 2013, which U.S. Patent Application No. 13/861273 is
(A) Priority is claimed under US Provisional Patent Application No. 61/623027 filed on April 11, 2012.
(B) Claims priority under US Provisional Patent Application No. 61/699125 filed on September 10, 2012.
(C) A partial continuation of U.S. Patent Application No. 13/786448 filed on March 5, 2013, which U.S. Patent Application No. 13/786448 was filed on March 5, 2012. It claims priority under Patent Application No. 61/606885.
(3) A partial continuation of U.S. Patent Application No. 14/714211 filed on May 15, 2015, which U.S. Patent Application No. 14/714211 is.
(A) Priority is claimed under US Provisional Patent Application No. 61/994094 filed May 15, 2014, and (b) US Patent Application No. 14/695008 filed April 23, 2015. This is a partial continuation application for the issue.
These applications are by reference fully incorporated as if their contents were fully described herein. All publications referred to below are also by reference fully incorporated, as if their contents were fully described herein.

The present invention relates to an optical bench subassembly, more particularly to an optical fiber subassembly based on an optical bench, and more particularly to a closed fiber optic feed based on an optical bench. It relates to a through subassembly.

Transmitting optical signals over fiber optic waveguides has many advantages and is versatile in use. A single or multiple fiber waveguides may be used to simply transmit visible light to a remote location. Complex telephone or data communication systems can transmit a large number of specific optical signals. Data communication systems include devices that connect optical fibers in an end-to-end connection, supplying, detecting, and / or controlling light to those devices, between optical and electrical signals. Includes optoelectronic or optical devices, including optical elements and electronic components, that perform the conversion.

For example, a transceiver (Xcvr) is an optoelectronic module that includes both a transmitting device (Tx) and a receiving device (Rx) combined with a circuit inside a module housing known in the art as a package. The package may be hermetically sealed to protect its contents from the surrounding environment. The transmitting device includes a light source (eg, VCSEL or DFB laser) and the receiving device includes an optical sensor (eg, a photodiode (PD)). In a conventional embodiment, the transceiver circuit configuration (including, for example, a laser driver, a transimpedance amplifier (TIA), etc.) is soldered onto a printed circuit board. Such transceivers generally have a substrate that forms the bottom or floor of the package (whether sealed or unsealed), and optoelectronic devices such as lasers and photodiodes It is soldered onto such a substrate. The optical fiber is either drawn through the wall of the package or connected to the outer surface of the package using a sealed feedthrough (assigned to the assignee / applicant of the present application in common with the present application, the contents of which are fully described herein. It is completely incorporated as if it were, see Patent Document 1).

The end of the optical fiber is optically coupled to an optoelectronic device held in the housing. The feedthrough element supports a portion of the optical fiber through an opening in the wall. In many applications, it is desirable to seal the optoelectronic device inside the optoelectronic module housing in order to protect the components from corrosion media, moisture and the like. Since the package of the optoelectronic module must be hermetically sealed as a whole, the feedthrough elements are also not hermetically sealed so that the electro-optic components inside the optoelectronic module housing are highly reliable and continuously protected from the surrounding environment. must not.

For proper operation, the optoelectronic device supported on the printed circuit board must efficiently couple the light to an external optical fiber. Some optoelectronic devices require a single-mode optical connection, which requires a tight alignment tolerance, typically less than 1 μm, between the fiber optic and the device. This is an active optical alignment approach in which the position and orientation of the optical fiber (s) is adjusted using mechanical elements until the amount of light passed between the fiber and the optoelectronic device is maximized. In use, it is a particular challenge in multi-fiber applications where multiple optical fibers must be optically aligned to multiple optoelectronic devices.

1A and 1B show a hermetically sealed optoelectronic package 500 having a hermetically sealed multifiber feedthrough 502, in which the hermetically sealed feedthrough 502 is supported by the floor of the package 500. It is actively aligned with the optical device 504 mounted on the submount 506. In this example, feedthrough 502 is assigned to Patent Document 2 (in common with the present application, assigned to the assignee / applicant of the present application, the contents of which are fully incorporated as if fully described herein). Similar to the optical coupling device disclosed in. The optical device 504 may include a VCSEL array and / or a PD array that is supported, for example, via a submount 506 and a printed circuit board 508 on the floor of the package. The printed circuit board 508 integrates other electronic components and circuits, and the package 500 may include several printed circuit boards. After the optical device 504 / submount 506 and other components are assembled within the package 500, the feedthrough 502 is provided through an opening 503 defined by the nose 50 on the side wall of the housing 501 of the package 500. Will be inserted. The fiber optic 20 array of the fiber optic cable 21 is supported by a feedthrough 502 and is active with respect to the optical device 504 so that the desired optical coupling efficiency is achieved between the optical device and the fiber optic 20 array. Aligned with. This process requires the optical device 504 and associated electronic circuit elements (not shown) to be pre-assembled within the package 500. The optical device 504 is activated / energized to send and receive an optical signal 22 to and from an array of optical fibers 20. Basically, when the signal 22 passed between the optical fiber 20 and the optical device 504 is maximum, the optical signal (from) to the optical fiber 20 is optimally coupled to the optical device 504. It can be said that it has been done. The feedthrough 502 is then soldered into the nose 50 on the package side wall of the housing 501 with the optical alignment established.

Since the VCSEL or PD must be in the energy supply state during the active alignment process, active optical alignment can be said to be a relatively complex and low throughput process. Integrated circuit manufacturers often have expensive capital equipment that allows submicron alignment (for example, wafer inspectors and handlers testing integrated circuits), but companies that package chips. Are generally those with lower performance machines (typically a few microns of alignment tolerance that are inadequate for single-mode devices) and often use manual operation. ..

Current state of the art is costly to include the package, eliminates the use of common electronics and assembly processes, and / or is often unsuitable for single-mode applications. Compared to closed feedthrough subassemblies, packages are more expensive assemblies (including expensive circuit components such as ICs). In addition, the active alignment and soldering process involves high-risk steps at the end of the entire packaging process, in that components must be pre-assembled within the package to support active alignment. In view of this, if the realization of active alignment fails due to a defective component that may have been attracted during the active alignment process, such failure is already contained within the package of the optical device. This can lead to the need to dispose of the entire package, including other components.

In addition, VCSEL and PD elements can be tested in static state prior to assembly, but tested in operating state until assembled in a package with the electronics configuration to drive those elements. Cannot be done. Therefore, the energization test process for VCSELs and PD elements (to identify early component defects under simulated load conditions) can only be performed after those components have been assembled into the package. .. This leads to further disposal of the package, which is a more expensive module because it is assembled (ie, lower production rate of the package) as a result of defective but relatively inexpensive VCSEL and PD elements. Can bring. VCSEL and PD elements are known to contribute to a relatively large number of defects in assembled packages.

Assembled by a relatively large and more compliant structural loop (represented by the dotted line L in FIG. 1B) that maintains the optical alignment between the optical device and the feedthrough, as shown in FIG. 1B. Another form of defect arises that leads to the disposal of the package. This long structural loop is more sensitive to thermal-mechanical deformations that can cause the package to deviate from the intended design specifications and thus can result in defective aspects.

U.S. Patent Application Publication No. 2013/0294732 U.S. Patent Application Publication No. 2016/0016218

What is needed is an improved structure for coupling fiber optic inputs / outputs to optoelectronic components / devices with established optical alignments, throughput, margin of error, manufacturability, It is a structure that improves usability, functionality, and reliability at a lower cost.

The present invention provides an improved structure for facilitating optical alignment of an optical device with respect to an optical bench to overcome the shortcomings of prior art. The present invention combines an optical bench with an optical device within a subassembly, allowing the optical coupling of the optical device to be aligned to the optical bench to be aligned outside the optoelectronic package assembly.

According to the present invention, the optical device is attached to the base of the optical bench with the optical alignment of the optical input / output of the optical device and the optical output / input of the optical bench established.

In one embodiment, the optical bench supports an optical element in the form of an optical waveguide (eg, an optical fiber). In one more specific embodiment, the base of the optical bench defines an alignment structure in the form of at least one groove to precisely support the end portion of the optical fiber. Optical elements (eg, lenses, prisms, reflectors, mirrors, etc.) may be provided in a precise relationship with respect to the end surface of the optical fiber. In one further embodiment, the optical element includes a structural surface, which may be planar reflective or concave (eg, aspherical mirrored).

In one embodiment, the optical device may be mounted on a submount that is attached to the base of the optical bench with an established optical alignment with the optical bench. Submounts are provided with circuits, electrical contact pads, circuit components (eg drivers for VCSELs and TIA for PDs), and other circuits and / or components associated with the operation of the optical device 12. May be good.

The optical device can be passively aligned with the optical bench (eg, depending on the alignment markings (not shown) on the base of the bench). Alternatively, the optical device and the optical bench may be actively aligned by sending an optical signal between the optical waveguide and the optical device in the optical bench. Optical devices (eg VCSELs and / or PDs) so as to allow active alignment with optical waveguides (eg, fiber optics) supported within the optical bench, independent of other components inside the package. Can be activated. After the optical alignment is achieved, the submount of the optical device is fixedly attached to the base of the optical bench.

In order to form the precise geometry and feature shape of the optical bench, the base of the optical bench is preferably formed by stamping a malleable material (eg metal). The optical bench subassembly may be configured to be hermetically sealed.

In another embodiment of the invention, the optical bench has multiple waveguides (eg, multiple) to operate with an array of multiple optical devices (multiple VCSELs and / or multiple PDs) mounted on a submount. Optical fiber) and structural reflective surfaces (eg mirror arrays) are configured to support.

The present invention pre-assembles optics and elements and optical devices precisely within an optical bench subassembly prior to assembling into a larger optoelectronic package. Subassemblies can be subjected to functional tests, including energization tests, at the subassembly level outside the optoelectronic package, which is more expensive due to premature defects in the optoelectronic device mounted inside the optoelectronic package. It is possible to reduce the waste of optoelectronic packages.

For a more complete understanding of the properties and benefits of the present invention, in addition to the preferred embodiments, refer to the following detailed description read with the accompanying drawings. In the drawings below, similar reference numbers refer to similar or similar parts throughout the drawing.

Diagram showing a closed optoelectronic package containing a closed fiber optic feedthrough Cross-sectional view taken along line 1B-1B of FIG. 1A FIG. 6 shows an optical bench subassembly in the form of a closed feedthrough including an integrated optical device according to one embodiment of the present invention. Cross-sectional view taken along line 2B-2B of FIG. 2A when attached to a sealed optoelectronic package. An enlarged view of the optical bench in the optical bench subassembly of FIG. 2 according to one embodiment of the present invention. The figure which showed the state after the assembly of the optical bench of FIG. 3A. An enlarged view of an optical bench in an optical bench subassembly according to another embodiment of the present invention. The figure which showed the state after the assembly of the optical bench of FIG. 4A. The figure which showed the alternative embodiment of the submount for an optical device in an optical bench subassembly. It is a figure which showed the assembly procedure of the closed type optoelectronic package, and is the figure explaining the assembly of an optical device assembly. The figure which showed the assembly procedure of the closed type optoelectronic package, and explained the assembly and active alignment of an optical device assembly to an optical bench. It is the figure which showed the assembly procedure of the closed type optoelectronic package, and is the figure explaining the assembly of the closed type optoelectronic package. The figure which showed the closed feedthrough in the state attached to the closed optoelectronic package.

Hereinafter, the present invention will be described with reference to various embodiments with reference to the drawings. Although the present invention has been described with respect to the best mode for achieving the object of the present invention, those skilled in the art will be able to provide these teachings without departing from the spirit and scope of the present invention. You can see that multiple variations can be achieved with consideration.

The present invention provides an improved structure for facilitating optical alignment of an optical device with respect to an optical bench to overcome the shortcomings of prior art. The present invention combines an optical bench with an optical device within a subassembly, allowing the optical coupling of the optical device to be aligned to the optical bench to be aligned outside the optoelectronic package assembly.

According to the present invention, the optical device is attached to the base of the optical bench with the optical alignment of the optical input / output of the optical device and the optical output / input of the optical bench established. Various embodiments of the invention incorporate some of the original concepts developed by the assignee of the invention, NanoPrecision Products Incorporated, which include optical data. Includes various proprietary products, including subassemblies of optical benches for transmission-related applications, and includes the concepts disclosed in the following patent publications commonly assigned to the assignee. Priority based on the pending application is claimed in this application.

For example, US Patent Application Publication No. 2013/03222818 describes an optical coupling device for routing optical signals in the form of an optical bench with a stamped structural surface for routing optical data signals. It discloses an optical coupling device having. The optical bench includes a metal base with a defined structural surface, which has a surface shape that bends, reflects, and / or reshapes incident light. The base further defines the alignment structure. This alignment structure is a precise optical alignment of the structural surface and the optical element so that light can be transmitted along a defined path between the structural surface and the optical element (eg, optical fiber). It is constructed with a surface feature shape that facilitates precise positioning of the optics on the base, and the structural surface and alignment structure are stamped with malleable metal material to provide an optical bench. Is integrally defined on the base by forming.

U.S. Patent Application Publication No. 2015/0355420 further discloses an optical coupling device for routing optical signals used within an optical communication module, among other things, an optical coupling device in the form of an optical bench. Thus, a structural surface having a surface shape that bends, reflects, and / or reshapes incident light discloses an optical coupling device defined on a metal base. An alignment structure is defined on the base. This alignment structure provides an optical alignment between the structural surface and the optical element so that light can be transmitted along a defined path between the structural surface and the optical element (eg, optical fiber). As such, it is configured with a surface feature shape that facilitates positioning of the optics on the base. The structural surface and alignment structure are integrally defined on the base by stamping the malleable metal material of the base. To allow light to be transmitted along a defined path between the structural surface and the optics, this alignment structure is based on the optical alignment between the structural surface and the optics. Facilitates passive alignment of optics above.

Patent Document 1 further discloses a closed optical fiber alignment assembly having an integrally formed optical element, particularly comprising a metal ferrule portion having a plurality of grooves for receiving an end portion of the optical fiber. Also disclosed is a closed fiber optic alignment assembly that includes an optical bench, wherein the plurality of grooves define the position and orientation of the above-mentioned end portion with respect to the ferrule portion. doing. The assembly includes integrally formed optics for coupling the inputs / outputs of the optical fiber to the optoelectronic devices within the optoelectronic module. The optical element may be in the form of a structural reflective surface. The ends of the optical fiber are arranged at a predetermined distance from the structural reflecting surface and are aligned with the structural reflecting surface. Structural reflective surfaces and optical fiber alignment grooves can be formed by stamping malleable metals and defining their characteristic shapes on a metal base.

U.S. Pat. No. 9,213,148 further discloses a similar sealed fiber optic alignment assembly, but the assembly does not include an integrally formed structural reflective surface.

U.S. Pat. No. 7,343,770 discloses a novel precision stamping system for manufacturing parts with low margins of error. Such an original stamping system can be implemented during various stamping processes to create the devices disclosed in the patent publications listed above. These stamping processes include the final overall geometry and the geometry of the surface feature shape (including reflective surfaces with the desired geometry that are precisely aligned with other defined surface feature shapes). Includes the process of stamping bulk materials (eg, metal blanks) to form with tight (ie small) tolerances.

Patent Document 2 further discloses a composite structure including a base having a main portion and an auxiliary portion of a dissimilar metallic material. The main part and auxiliary part are molded by stamping. When the auxiliary part is stamped, the auxiliary part interlocks with the base and at the same time forms the desired structural feature shape on the auxiliary part (eg, structural reflective surfaces, feature shapes for fiber optic alignment, etc.). To do. With this approach, relatively less important structural features shapes can be formed on the bulk of the base with less effort to maintain relatively large tolerances, while more important structural features present on the auxiliary parts. Shapes are molded more precisely with further consideration that defines dimensions, geometry and / or finish conditions with less tolerance. The auxiliary portion may include an additional composite structure of two dissimilar metallic materials with different properties for stamping different structural feature shapes. This stamping approach follows the earlier stamping approach in U.S. Pat. No. 7,433,770, in which the bulk material used for stamping is a homogeneous material (eg, strips of metal, such as Kovar or aluminum). On the other hand, it brings improvement. The stamping process produces a structural feature shape from a single homogeneous material. Therefore, a plurality of different feature shapes share the properties of the material, and the properties may not be optimal for one or more feature shapes. For example, a material with properties suitable for stamping feature shapes for alignment can be used to stamp reflective surface feature shapes with optimal light reflection efficiency to reduce loss of optical signals. It may not have suitable properties.

US Pat. No. 8,961034 is a method of manufacturing a ferrule for supporting an optical fiber in an optical fiber connector, in which a metal is used to form a body having a plurality of substantially U-shaped open grooves in the longitudinal direction. Each of the plurality of longitudinal open grooves includes a step of stamping the blank, each of which has a longitudinal opening provided on the surface of the body, each of which is formed by clamping an optical fiber. It discloses a method of sizing to hold the optical fiber firmly in the groove. The optical fiber is firmly held within the body of the ferrule without the need for additional fiber holding means.

WO 2014/011283 discloses a ferrule for fiber optic connectors that overcomes many of the shortcomings of prior art ferrules and connectors and provides further improvements to the pinless alignment ferrules described above. doing. The optical fiber connector includes an optical fiber ferrule, and the above optical fiber ferrule is used because an alignment of an array consisting of a plurality of optical fibers and a plurality of optical fibers held in another ferrule is realized by using a sleeve. , Has a generally elliptical cross section.

The plurality of original concepts described above are incorporated herein by reference and are referred to below for ease of disclosure of the present invention. The present invention is an exemplary embodiment of a closed fiber optic feedthrough for a closed optoelectronic package, the optical fiber feedthrough comprising an optical bench subassembly with an integrated optical device. Will be disclosed in connection with.

2A and 2B are one embodiment of a sealed fiber optic feedthrough in the form of an optical bench subassembly 10 comprising an optical bench 11 with an integrated optical device 12 according to one embodiment of the present invention. Shows the morphology. In the illustrated embodiment, the optical device 12 is mounted on a submount 14 mounted on the optical bench 11 at a position where alignment with the optical input / output of the optical bench 11 is established. (See optical signal 22 in FIG. 2B).

3A and 3B are views showing the structure of the optical bench 11 in the optical bench subassembly 10 more clearly. In this embodiment, the optical bench 11 is similar to the sealed multi-fiber alignment subassembly disclosed in Patent Document 2 of the assignee of the present application cited above. The optical bench supports one or more optical waveguides, which are the plurality of optical fibers 20 of the optical fiber cable 21 in the illustrated example. In the case of multi-fiber, the base 13 of the optical bench 11 defines a plurality of open grooves 16 that support the optical fiber 20 and defines or supports optical elements (eg, lenses, prisms, reflectors, mirrors, etc.). In the illustrated example, the optics include an array of multiple structural reflective surfaces 17, each corresponding to one optical fiber 20. The reflecting surface may be one that performs planar reflection, or may be contoured so as to perform concave reflection (for example, aspherical mirror surface) or convex reflection. In the illustrated example, the base 13 has a composite structure that includes an auxiliary portion 30 made of a material dissimilar to the material of the rest of the base 13 (ie, the main portion 13'). The base 13 including the auxiliary portion 30 is stamped from a malleable material to form the geometric shape of the body and the desired surface feature shape. In this case, the auxiliary portion is formed by stamping a malleable metal material to form an array of structural reflective surfaces 17 and grooves 18, while the base 13 has grooves 16 and other illustrated structures. Stamped from another malleable metal material to form. As disclosed in Patent Document 2, when the auxiliary portion 17 is stamped, the auxiliary portion 17 interlocks with the base 13 in a manner similar to a rivet, and at the same time, on the auxiliary portion 30, the structural reflective surface 17 is formed. The desired structural feature shape, including the array and the optical fiber alignment groove 18 for supporting the end portion of the optical fiber 20, is provided at the end surface (ie, input / output) of the optical fiber 20 corresponding to each reflective surface 17. And are formed so that they are maintained in a precise relationship. In this embodiment, the auxiliary portion 17 and the main portion 13'are stamped using different metal materials.

The open grooves 16 and 18 clamp and clamp the optical fiber in the groove without the need for additional fixing means (eg, without the use of epoxies, etc.) as disclosed in US Pat. No. 8,961034. It may be configured and formed according to the stamped open groove. In the illustrated embodiment, a cover 15 is provided to cover the base 13 without covering the structural reflective surface 17. A sealing epoxy (eg, glass epoxy) is applied to fill the perimeter of the portion of the optical fiber 20 within the cavity 19 between the cover 15 and the base 13, thereby forming a sealing seal. The optical bench 11 is a closed feedthrough. This sealed feedthrough 502 of FIG. 1A, except that the optical bench 11 has an optical device integrated on the optical bench 11 to form the optical bench assembly 10 according to the present invention. It has a function similar to that of, and can be used together with an optoelectronic package. Further ingenuity of a similar closed feedthrough structure can be found in Patent Document 1.

4A and 4B show another embodiment of the optical bench 11'similar to the optical bench 11 of FIGS. 3A and 3B except for the fiber optic cable 21. In this embodiment, the optical bench 11'is provided with a removable connection in the form of a ferrule 30. The ferrule 30 replaces the optical fiber 21 extending away from the optical bench 11'while allowing the front far end portion of the optical fiber to be supported by grooves 16 and 18 inside the optical bench 11'. Supports the rear end portion of the short portion of the fiber 20. The ferrule 30 may be configured to have a generally elliptical cross section, as disclosed in WO 2014/011283. For example, sleeves (not shown) may be used to connect to fiber optic cables (eg, patch cables) that are terminated with similar ferrules. In this embodiment, if the connecting optical fiber becomes defective, the light does not need to replace the entire optoelectronic package to which the optical bench 11'is permanently or fixedly mounted. The fiber can be pulled out and replaced.

Next, moving to the optical device, in the embodiment illustrated in FIGS. 2A and 2B, the optical device 12 is mounted on the submount 14 to form the optical device assembly 23. Submount 14 is provided with circuits, electrical contact pads, circuit components (eg drivers for VCSELs and TIA for PDs), and other circuits and / or components associated with the operation of the optical device 12. May be good.

6A to 6C show the procedure for assembling the sealed optoelectronic package. FIG. 6A illustrates the assembly of an optical device (transmitting or receiving device or transceiver) assembly, FIG. 6B illustrates the assembly and active alignment of the optical device assembly to an optical bench, FIG. 6C. , Explains the assembly of a sealed optoelectronic package.

Referring to FIG. 6A, when the optical device 12 is a transmitting device such as a VCSEL, the optical device 12 is mounted on the submount 14 together with the driver chip. The VCSEL may be wire bonded to the circuit on the submount 14. Tests may be performed to ensure that the VCSEL can operate to transmit an optical signal after assembly. When the optical device 12 is a receiving device such as a PD, the optical device 12 is mounted on the submount 14 together with the TIA chip. The PD may be wire bonded to the circuit on the submount 14. After assembly, tests may be performed to see if the PD can operate to receive an optical signal and output an electrical signal. In the case of transceivers, the above steps may be combined to test individual receive and transmit capabilities. The optical device 12 may include a plurality of receiving devices, transmitting devices and / or transceivers mounted on the submount 14.

Referring to FIG. 6B, the submount 14 of the optical device assembly is located at a position where an optical alignment is established between the optical device 12 and the optical bench 11, that is, the input / output of the optical device 12 is the output / output of the optical bench 11. Optically aligned with the input, the optical path 22 is attached to the opposing surface of the base 13 of the optical bench 11 at a position such that the optical path 22 achieves the desired optical coupling efficiency between the optical device 12 and the optical fiber 20. In the embodiment illustrated in FIG. 2B, the optical path 22 is an optical path between the input / output end face of the optical fiber 20 and the output / input of the corresponding optical device 12, with a reflective surface 17 (eg, an aspheric mirror surface). It is bent and remolded. In the illustrated embodiment, more specifically, the optical path extends in a direction deviating from the plane of the base 13, and this direction is substantially perpendicular to the plane of the base 13. As shown in FIG. 2B, the plane of the submount 14 is parallel to the plane of the base 13. A frame 32 is provided as a spacer between the submount 14 and the facing surface of the base 13 in order to provide a space for accommodating the optical device 12 between the submount 14 and the base 13. In the illustrated embodiment, there are an array of four reflective surfaces 17 corresponding to an array of four optical fibers 20.

The optical device 12 can be passively aligned with the optical bench 11 (eg, depending on the alignment marks (not shown) provided on the base of the bench 11). Alternatively, an optical signal is sent between the optical waveguide (that is, the optical fiber 20) in the optical bench 11 and the optical device 12, and the intensity of the optical signal in the optical path is measured to indicate a state in which the optical alignment is established. By identifying the optical coupling, the optical device 12 and the optical bench 11 may be actively aligned. The optical device 12 (eg, VCSEL and / or PD) and the optical fiber supported within the optical bench 11 without having to rely on other components inside the optoelectronic package to which the optical bench subassembly 10 is mounted. Can be activated to allow for active alignment of. For example, when the optical device 12 is a transmitting device (eg, VCSEL), the optical device 12 emits light to the reflective surface 17 so as to be redirected to the end surface of the corresponding optical fiber 20. Energy can be supplied. In order to identify the optical coupling between the transmitting device and the optical bench 11, the intensity of the optical signal propagated through the reflective surface 17 through the corresponding optical fiber is measured. When the optical device 12 is a receiving device (eg PD), an optical signal is supplied through the optical fiber and reflected by the reflective surface to the corresponding receiving device. The degree of optical coupling between the optical fiber and the receiving device can be determined from the electrical output of the receiving device (corresponding to the strength of the received optical signal), thereby identifying the alignment state. The active alignment process involves moving the optical device 12 relative to the reflective surface 17 in the plane of the submount 14 while the optical coupling efficiency is identified relative to the alignment point. Conductive pads are provided on the surface of the submount opposite to the base 13 to facilitate electrical connections for active alignment.

Once the desired optical alignment is achieved, the submount 14 of the optical device 12 is fixedly attached to the base of the optical bench, for example by laser welding, soldering or epoxy.

After assembling the optical bench subassembly 10, the optical bench subassembly 10 may be subjected to an energization test in order to eliminate premature defects, and may be further subjected to a functional test.

The above embodiment of the optical bench subassembly 10 including the integrated optical device 12 is a closed feedthrough with the integrated optical device 12.

Referring to FIG. 6C, as shown in FIG. 2B, after the assembly of the optical bench subassembly 10 is completed, the optical bench subassembly 10 is sealed in the optoelectronic package 500'(eg by soldering). It is attached. The optoelectronic package 500'is similar to package 500 of FIG. 1A, except that the optical device 12 is integrated into the optical bench subassembly 10 with an optical alignment established with respect to the optical bench 11. It may be there. Various components (for example, IC, chip, submount, circuit board, etc.) are integrated in the optoelectronic package 500'. The optical bench subassembly 10 as a sealed feedthrough is inserted through the opening of the nose 50 at the side wall of the housing 501'of the package 500'and sealed (eg by soldering). Compared to the situation in FIG. 1B, the position of this feedthrough with respect to package 500'is less important. This is because no optical alignment is required between the feedthrough and the external optical device within the package 500'. As shown in FIG. 2B, the submount is provided in the package 500'with a via hole 36 penetrating the substrate of the submount 14 to connect to the optical device 12 on the opposite side of the submount 14. 14 may be soldered to a printed circuit board 39 (which may be a flexible printed circuit board). A ball grid array (BGA) with microsolder ball contacts may be configured on the submount 14. Other electrical connections may include the optical bench subassembly 10'in the embodiment of FIG. 5, which is provided on the side surface of the submount 14'in the optical bench subassembly 10'of the embodiment of FIG. The wound winding trace 38 is electrically connected to a circuit board (not shown) within the package 500'by wire bonding or a flexible circuit connection element 37. Alternatively, spring pins (not shown) may be configured to implement an electrical connection between the submount and the printed circuit board within the package 500'. These electrical connections absorb error motion and stress due to thermal expansion / contraction and do not affect the optical alignment between optical devices integrated on the optical bench substrate of the optical bench subassembly.

FIG. 7 shows a sealed feedthrough / optical bench assembly 10 attached to a sealed optoelectronic package 500'. Other electronic and circuit components are excluded from FIG. The sealed cover of the sealed optoelectronic package 500'is also excluded from the figure.

After assembling the optical bench subassembly 10 into a sealed optoelectronic package 500', the package 500' may be subjected to an energization test to eliminate premature defects and may be further functionally tested. ..

Optics because the present invention pre-assembles optics and elements and optical devices into an optical bench subassembly prior to assembling the optical bench subassembly into a larger optoelectronic package. Bench subassemblies can be subjected to functional tests, including energization tests, at the subassembly level, outside the optoelectronic package. Therefore, it is possible to reduce the disposal of more expensive packages (including expensive circuit components such as ICs) caused by early generation defects of the optical device mounted inside the package. The active alignment process for optical bench subassemblies is much easier. In addition, there is a much smaller, more robust, structural loop between the optical bench and the optical device. Therefore, according to the present invention, higher production rates, higher reliability and lower manufacturing costs can be achieved as a whole for optoelectronic packages that include sealed feedthroughs.

Although the present invention has been specifically shown and described above with reference to the preferred embodiments, those skilled in the art will make various changes regarding the embodiments and details without departing from the spirit, scope and teaching contents of the present invention. You will understand that is possible. Therefore, the inventions disclosed herein should be considered merely for explanatory purposes and should be limited in scope only as specified in the appended claims.
Other embodiments
1. 1. In an optical bench subassembly for routing optical signals
It ’s an optical bench,
base,
A structural surface defined on the base, which has a surface shape that reshapes and bends incident light.
Optical elements, as well
An alignment structure defined on the base, wherein the alignment structure is said on the base such that an optical signal is transmitted along a defined optical path between the structural surface and the optical element. It is configured with a surface feature shape for arranging the optical element in a state where the structural surface and the optical alignment are established, and the optical path extends from the structural surface to the outside of the base. Alignment structure,
Optical bench, including, and
An optical device assembly that includes an optical device that is attached to the base such that the optical device is in a state of establishing optical alignment with respect to the structural surface along the optical path. Optical device assembly,
An optical bench subassembly characterized by including.
2. The optical bench subassembly according to the first embodiment, wherein the optical element includes an optical waveguide.
3. 3. The optical bench subassembly according to the second embodiment, wherein the optical waveguide includes an array of a plurality of optical fibers, and the structural surface includes an array of a plurality of structural reflecting surfaces.
4. A cover attached to the base in a hermetically sealed manner so as to hermetically seal the perimeter of a portion of the array of the plurality of optical fibers, the cover extending so as to cover the structural surface. The optical bench subassembly according to embodiment 3, wherein the optical bench subassembly further comprises a cover thereby providing a closed feedthrough.
5. The optical device assembly includes a submount on which the optical device is mounted, the submount of the optical bench such that the optical device is in a state in which optical alignment is established with respect to the structural surface. The optical bench subassembly according to embodiment 4, characterized in that it is attached to a base.
6. The optical bench subassembly according to embodiment 5, wherein the optical device includes a transmitting device, a receiving device, or a transceiver.
7. The optical bench subassembly according to embodiment 6, wherein the optical device is passively aligned with the structural surface.
8. The optical bench subassembly according to embodiment 6, wherein the optical device is actively aligned with the structural surface.
9. The optical bench subassembly according to embodiment 1, wherein the structural surface and the alignment structure are integrally defined on the base by stamping the malleable material of the base.
10. The base is
The main part of the first material, which defines the first structural feature shape, and
An auxiliary portion of the second material, which defines a second structural feature shape on a second material different from the first material.
Including
The auxiliary portion is structurally coupled to the base, thereby defining the main portion of the first material in which the first structural feature shape is defined and the second structural feature shape. A composite structure is formed including the auxiliary portion of the second material, and the first structural feature shape and the second structural feature shape define the optical path for routing an optical signal. 9. The optical bench subassembly according to embodiment 9.
11. housing,
Electronic components integrated inside the housing, and
The optical bench subassembly according to embodiment 4, which is hermetically attached to the housing.
A sealed optoelectronic package characterized by containing.
12. The sealed optoelectronic package according to embodiment 11, wherein the optical bench subassembly is subjected to a functional test before being hermetically sealed in the housing.
13. In how to assemble an optical bench subassembly for routing optical signals
It ’s an optical bench,
base,
A structural surface defined on the base, which has a surface shape that reshapes and bends incident light.
Optical elements, as well
An alignment structure defined on the base, wherein the alignment structure is said on the base such that an optical signal is transmitted along a defined optical path between the structural surface and the optical element. It is configured with a surface feature shape for arranging the optical element in a state where the structural surface and the optical alignment are established, and the optical path extends from the structural surface to the outside of the base. Alignment structure,
The process of providing an optical bench, including
The process of providing an optical device assembly, including an optical device,
A step of optically aligning the optical device with respect to the structural surface along the optical path, and
The process of attaching the optical device assembly to the base after the optical alignment has been established,
A method characterized by including.
14. The optical element comprises an array of a plurality of optical fibers, the structural surface comprises an array of a plurality of structural reflective surfaces, and the method hermetically seals the perimeter of a portion of the array of the plurality of optical fibers. As such, it further comprises the step of providing a cover that is attached to the base in a hermetically sealed manner, wherein the cover does not extend to cover the structural surface, thereby providing a hermetically sealed feedthrough. The method according to the thirteenth embodiment.
15. The optical device assembly includes a submount on which the optical device is mounted, the submount of the optical bench such that the optical device is in a state in which optical alignment is established with respect to the structural surface. 14. The method of embodiment 14, characterized in that it is attached to a base.
16. 15. The method of embodiment 15, wherein the optical device comprises a transmitting device, a receiving device or a transceiver.
17. 16. The method of embodiment 16, wherein the optical device is actively optically aligned with respect to the structural surface.
18. 17. The method of embodiment 17, wherein the optical bench assembly is functionally tested at the subassembly level, the functional test comprising an energization test.
19. In the method of forming a sealed optoelectronic package,
The process of providing the housing,
The process of integrating electronic components inside the housing, and
The step of attaching the optical bench subassembly assembled by the method according to the fourteenth embodiment to the housing in a closed manner.
A method characterized by including.
20. 19. The method of embodiment 19, wherein the optical bench subassembly is subjected to a functional test, including an energization test, prior to being hermetically sealed in the housing.

10,10'Optical Bench Subassembly 11,11'Optical Bench 12 Optical Device 13 Base 14,14' Submount 15 Cover 16 Open Groove 17 Structural Reflection Surface 18 Groove 19 Cavity 20 Optical Fiber 21 Optical Fiber Cable 22 Optical Signal 23 Light Device Assembly 32 Frame 36 Via Hole 39 Printed Circuit Board 50 Nose 500,500'Optical Electronics Package 501,501' Housing 502 Feed Through

Claims (13)

In an optical bench subassembly for routing optical signals
It ’s an optical bench,
base,
A structural reflective surface that is at least one structural reflective surface defined on the surface of the base and has a surface shape that reshapes and bends incident light.
At least one optical fiber,
At least one optical fiber alignment groove defined on the surface of the base, the alignment groove transmitting an optical signal along a defined optical path between the structural reflective surface and the optical fiber. As described above, the optical fiber is configured to be arranged on the base in a state where the structural reflection surface and the optical alignment are established, and the optical path extends from the structural reflection surface to the outside of the base. A cover attached to the base on the side by the optical fiber alignment groove so as to hermetically seal the alignment groove and the surrounding space of a part of the optical fiber, wherein the cover has the structure. An optical bench that includes a cover and an optical device assembly that includes a submount and an optical device mounted on it that does not extend over the reflective surface, thereby providing a sealed feedthrough. The submount is attached to the base of the optical bench such that the optical device faces the structural reflective surface and the optical alignment is established with respect to the structural reflective surface along the optical path. , the submount includes an electrical contact for mounting to an external circuit, and, prior Symbol light device taken on the base of the optical bench so that the state of the optical alignment is established with respect to the structure reflecting surface An optical device assembly, wherein the attached submount can be mounted on the circuit.
An optical bench subassembly characterized by including. The optical bench subassembly according to claim 1, further comprising an array of a plurality of optical fibers and an array of a plurality of structural reflecting surfaces corresponding to the array of optical fibers. The cover is attached to the base in a hermetically sealed manner so as to hermetically seal the perimeter of a portion of the array of the plurality of optical fibers so that the cover covers the array of structural reflective surfaces. 2. The optical bench subassembly according to claim 2, wherein the optical bench is non-extended, thereby providing a closed feedthrough. Claims 1 to 3 , wherein the structural reflective surface and the corresponding optical fiber alignment groove are integrally defined on the base by stamping the malleable material of the base. The optical bench subassembly according to any one of the above. A housing having an opening sized to receive the optical bench of the optical bench subassembly according to any one of claims 1 to 4 through the opening.
Electronic components and circuits integrated within the housing, and the structural reflective surface of the optical bench within the optical bench subassembly mounted in a hermetically sealed manner in the opening of the housing, optics with respect to the optical device assembly. An optical bench, which is the optical bench of the optical bench subassembly to be aligned, wherein the submount is mounted on the circuit via the electrical contact.
A sealed optoelectronic package characterized by containing. The structural reflecting surface reshapes the light and connects the input / output of the optical fiber and the optical device independently of the reflective optical element between the input / output of the optical fiber and the optical device. The sealed optoelectronic package according to claim 5, wherein the package is configured as described above. In how to assemble an optical bench subassembly for routing optical signals
It ’s an optical bench,
base,
A structural reflective surface that is at least one structural reflective surface defined on the surface of the base and has a surface shape that reshapes and bends incident light.
At least one optical fiber,
At least one optical fiber alignment groove defined on the surface of the base, the alignment groove transmitting an optical signal along a defined optical path between the structural reflective surface and the optical fiber. As described above, the optical fiber is configured together with the surface characteristic shape for arranging the optical fiber on the base in a state where the structural reflection surface and the optical alignment are established, and the optical path is formed from the structural reflection surface to the base. A cover attached to the base on the side by the optical fiber alignment groove so as to hermetically seal the alignment groove and the surrounding space of a part of the optical fiber, which extends to the outside. A step of providing an optical bench that includes a cover, wherein the cover does not extend to cover the structural reflective surface, thereby providing a closed feedthrough.
A process of providing an optical device assembly comprising a submount and an optical device mounted on it, wherein the submount comprises electrical contact for mounting on an external circuit.
The step of optically aligning the optical device with respect to the structural reflective surface along the optical path, and optically between the structural reflective surface of the optical bench and the optical device prior to mounting on the circuit. The step of attaching the submount of the optical device assembly to the base of the optical bench after the alignment has been established.
A method characterized by including. The optical bench comprises an array and cover of a plurality of optical fibers defined on the base, the structural reflective surface comprises an array of a plurality of structural reflective surfaces defined on the base, the method. A step of attaching the cover to the base in a hermetically sealed manner is further included such that the surrounding space of a part of the array of the plurality of optical fibers is hermetically sealed, and the cover extends so as to cover the structural reflective surface. 7. The method of claim 7 , characterized in the absence, thereby providing a closed feedthrough. 7. The method of claim 7 or 8 , wherein the optical device comprises a transmitting device, a receiving device or a transceiver. 7. The method of claim 7 or 8 , wherein the optical device is actively optically aligned with respect to the structural reflective surface. The optical bench subassembly, tested function in the sub-assembly level, characterized in that it comprises a burn-in before the functional test mounting the optical bench subassembly hermetic optoelectronic package, any one of claims 7-10 The method described in paragraph 1. In the method of forming a sealed optoelectronic package,
The step of providing a housing having an opening sized to receive the optical bench of the optical bench subassembly according to any one of claims 7 to 11 through the opening.
After the process of integrating electronic components and circuits within the housing and the optical bench being optically aligned with respect to the optical device assembly in the optical bench subassembly, the optical bench of the optical bench subassembly is The process of attaching to the opening of the housing in a closed manner,
A method characterized by including. The optical bench subassembly attaches the optical bench to the housing in a sealed manner, with the structural reflective surface of the optical bench established in the optical bench subassembly with an optical alignment to the optical device assembly. The method according to claim 12 , wherein the method is previously subjected to a functional test including an energization test.

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