Unitary optical cradle

Abstract

A unitary optical cradle includes a receiving area on a first major side of the unitary optical cradle for receiving and securing an optical ferrule and a light redirecting element and a plurality of spaced apart substantially parallel optical lightguides on an opposite second major side. The unitary optical cradle is configured to be permanently bonded to a substrate with the optical lightguides at least partially secured within corresponding optical fiber-grooves of the substrate in one-to-one correspondence. Central light rays from optical fibers received and secured in the optical ferrule, enter the unitary optical cradle through the receiving area, are redirected by the light redirecting element from a first direction to a different second direction, are guided along, and substantially confined in, the optical lightguides in one-to-one correspondence, exit the optical lightguides, and optically couple to a plurality of optical elements of the substrate in one-to-one correspondence.

Description

PA102794W002UNITARY OPTICAL CRADLETechnical Field

[0001] The present disclosure relates to a unitary optical cradle.Background

[0002] Typically, photonic integrated circuits (PICs) guide optical data signals around a circuit, where they are brought into or emitted out of the PIC via a coupler. The coupler bridges the circuit and an optical fiber carrying the optical data signals to an intended destination. A significant challenge in the PIC is lack of commercially available interconnect solutions that may provide optical connections with precise and hyper-sensitive alignment between the coupler and the PIC, while meeting requirements of technology integrators and outsourced semiconductor assembly and testing (OSAT) businesses.Summary

[0003] In a first aspect, the present disclosure provides a unitary optical cradle. The unitary optical cradle is configured to removably receive and secure an optical ferrule and be permanently bonded to a substrate that includes at least one first optical fiber-groove optically aligned with at least one first optical element. The at least one first optical fiber-groove is configured to receive at least one first optical fiber so that a first central light ray from the first optical fiber optically couples to the at least one first optical element. The unitary optical cradle includes a receiving area on a first major side of the unitary optical cradle. The receiving area is for receiving and securing the optical ferrule. The unitary optical cradle further includes a first light redirecting element and at least one optical lightguide on an opposite second major side of the unitary optical cradle. Furthermore, the unitary optical cradle is configured to be disposed on the substrate so that the at least one optical lightguide is at least partially disposed in the at least one first optical fiber-groove in one-to-one correspondence. When a second optical fiber is optically coupled to the optical ferrule and the optical ferrule is removably received and secured in the receiving area of the unitary optical cradle, a second central light ray from the second optical fiber sequentially enters the optical ferrule, is redirected for a first time by a second light redirecting element of the optical ferrule from a first direction to a different second direction, exits the optical ferrule, and enters the unitary optical cradle through the receiving area of the unitary optical cradle. Furthermore, the second central light ray is redirected for a second time by the first light redirecting element of the unitary optical cradle from a third direction to a different fourth direction, is guided along, and substantially confined in, the at least one optical lightguide, exits from an end face of the at least one optical lightguide, and optically couples to the at least one first optical element.

[0004] In a second aspect, the present disclosure provides a unitary optical cradle. The unitary optical cradle includes a receiving area on a first major side of the unitary optical cradle for receiving and securing an optical ferrule. The unitary optical cradle further includes a light redirecting element and a plurality of spaced apart substantially parallel optical lightguides on an opposite second major side of the unitary optical cradle. The unitary optical cradle is configured to be permanently bonded to a substrate with the optical lightguides at least partially secured within corresponding optical fibergrooves of the substrate in one-to-one correspondence. Central light rays from optical fibers are received and secured in the optical ferrule, enter the unitary optical cradle through the receiving area of the unitary optical cradle, are redirected by the light redirecting element of the unitary optical cradle from a first direction to a different second direction, are guided along, and substantially confined in the optical lightguides in one-to-one correspondence, exit the optical lightguides from corresponding end faces of the optical lightguides, and optically couple to a plurality of optical elements of the substrate in one-to-one correspondence.

[0005] The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.Brief Description of the Drawings

[0006] Exemplary embodiments disclosed herein may be more completely understood in consideration of the following detailed description in connection with the following figures. The figures are not necessarily drawn to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

[0007] FIGS. 1A and IB are different schematic top perspective views of a unitary optical cradle and an optical ferrule removably received and secured in the unitary optical cradle, according to an embodiment of the present disclosure;

[0008] FIGS. 2 A and 2B are different schematic bottom perspective views of the unitary optical cradle and the optical ferrule removably received and secured in the unitary optical cradle, according to an embodiment of the present disclosure;

[0009] FIG. 3 is a schematic perspective exploded view of the unitary optical cradle and the optical ferrule, according to an embodiment of the present disclosure;

[0010] FIG. 4 is a schematic sectional perspective view of the unitary optical cradle and the optical ferrule removably received and secured in the unitary optical cradle, according to an embodiment of the present disclosure;

[0011] FIG. 5 is a schematic sectional side view of the unitary optical cradle and the optical ferrule removably received and secured in the unitary optical cradle, according to an embodiment of the present disclosure;

[0012] FIG. 6 is a schematic perspective view of a substrate including at least one first optical fiber, according to an embodiment of the present disclosure;

[0013] FIG. 7 is a schematic sectional front view of the substrate including the at least one first optical fiber, according to an embodiment of the present disclosure; and

[0014] FIG. 8 is a schematic sectional view of the substrate including at least one optical lightguide, according to an embodiment of the present disclosure.Detailed Description

[0015] In the following description, reference is made to the accompanying figures that form a part thereof and in which various embodiments are shown by way of illustration. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

[0016] In the following disclosure, the following definitions are adopted.

[0017] As used herein, all numbers should be considered modified by the term “about”. As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably.

[0018] As used herein as a modifier to a property or attribute, the term “generally”, unless otherwise specifically defined, means that the property or attribute would be readily recognizable by a person of ordinary skill but without requiring absolute precision or a perfect match (e.g., within + / - 20 % for quantifiable properties).

[0019] The term “substantially”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 10% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0020] The term “about”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 5% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0021] As used herein, the terms “first” and “second” are used as identifiers. Therefore, such terms should not be construed as limiting of this disclosure. The terms “first” and “second” when used in conjunction with a feature or an element can be interchanged throughout the embodiments of this disclosure.

[0022] As used herein, “at least one of A and B” should be understood to mean “only A, only B, or both A and B”.

[0023] Typically, photonic integrated circuits (PICs) guide optical data signals around a circuit, where they are brought into or emitted out of the PIC via a coupler. The coupler bridges the circuit and an optical fiber carrying the optical data signals to an intended destination. A significant challenge in the PICs is lack of commercially available interconnect solutions that may provide connections with precise and hyper-sensitive alignment between the coupler and the PIC, whilemeeting requirements of technology integrators and outsourced semiconductor assembly and testing (OS AT) businesses. A common problem for alignment of connectors is a need for precise and hypersensitive alignment between the connector and input / output ports of the PICs.

[0024] The present disclosure relates to a unitary optical cradle. The unitary optical cradle is configured to removably receive and secure an optical ferrule and be permanently bonded to a substrate that includes at least one first optical fiber-groove optically aligned with at least one first optical element. The at least one first optical fiber-groove is configured to receive at least one first optical fiber so that a first central light ray from the first optical fiber optically couples to the at least one first optical element. The unitary optical cradle includes a receiving area on a first major side of the unitary optical cradle. The receiving area is for receiving and securing the optical ferrule. The unitary optical cradle further includes a first light redirecting element and at least one optical lightguide on an opposite second major side of the unitary optical cradle. Furthermore, the unitary optical cradle is configured to be disposed on the substrate so that the at least one optical lightguide is at least partially disposed in the at least one first optical fiber-groove in one-to-one correspondence. When a second optical fiber is optically coupled to the optical ferrule and the optical ferrule is removably received and secured in the receiving area of the unitary optical cradle, a second central light ray from the second optical fiber sequentially enters the optical ferrule, is redirected for a first time by a second light redirecting element of the optical ferrule from a first direction to a different second direction, exits the optical ferrule, and enters the unitary optical cradle through the receiving area of the unitary optical cradle. Furthermore, the second central light ray is redirected for a second time by the first light redirecting element of the unitary optical cradle from a third direction to a different fourth direction, is guided along, and substantially confined in, the at least one optical lightguide, exits from an end face of the at least one optical lightguide, and optically couples to the at least one first optical element.

[0025] Therefore, the optical ferrule is separable from the unitary optical cradle that is permanently bonded to the substrate. The unitary optical cradle may enable compatibility with an OSAT assembly process, such as solder-reflow compatibility, high-yield for final module assemblies, and acceptably short durations for alignment and attachment of components.

[0026] Further, the at least one optical lightguide of the unitary optical cradle may fit into the at least one first optical fiber-groove of the substrate. This may provide a passive-alignment, especially along a plane of the substrate. Therefore, an integration of the at least one optical lightguide into the unitary optical cradle may enhance a reliability and a yield of an attachment step of the OSAT assembly process.

[0027] Referring now to figures, FIGS. 1A-1B are different schematic top perspective views of a unitary optical cradle 100 and an optical ferrule 200 removably received and secured in the unitary optical cradle 100, according to an embodiment of the present disclosure. FIGS. 2A and 2B are different schematic bottom perspective views of the unitary optical cradle 100 and the optical ferrule200 removably received and secured in the unitary optical cradle 100, according to an embodiment of the present disclosure.

[0028] FIG. 3 is a schematic perspective exploded view of the unitary optical cradle 100 and the optical ferrule 200, according to an embodiment of the present disclosure. FIG. 4 is a schematic sectional perspective view of the unitary optical cradle 100 and the optical ferrule 200 removably received and secured in the unitary optical cradle 100, according to an embodiment of the present disclosure. FIG. 5 is a schematic sectional side view of the unitary optical cradle 100 and the optical ferrule 200 removably received and secured in the unitary optical cradle 100, according to an embodiment of the present disclosure.

[0029] Referring to FIGS. 1A-1B to 5, the unitary optical cradle 100 defines mutually orthogonal x, y, and z-axes. The y-axis is defined along a length of the unitary optical cradle 100, while the x- axis is defined along a breadth of the unitary optical cradle 100. The z-axis is defined along a thickness of the unitary optical cradle 100.

[0030] The unitary optical cradle 100 is configured to removably receive and secure the optical ferrule 200 and be permanently bonded to a substrate 10 (shown in FIG. 5) that includes at least one first optical fiber-groove 11 optically aligned with at least one first optical element 12.

[0031] In some embodiments, the at least one first optical fiber-groove 11 is a plurality of substantially parallel first optical fiber-grooves 11. In such cases, the at least one first optical fibergroove 11 may be interchangeably referred as “the plurality of first optical fiber-grooves 11” or “the plurality of optical fiber-grooves 11” herein.

[0032] In some embodiments, the at least one first optical element 12 is a plurality of first optical elements 12. In such cases, the at least one first optical element 12 may be interchangeably referred as “the plurality of first optical elements 12” or “the plurality of optical elements 12” herein. In some embodiments, the at least one first optical element 12 includes an optical waveguide, an optical detector, or a light emitter.

[0033] The unitary optical cradle 100 includes a receiving area 20 on a first major side 101 of the unitary optical cradle 100 for receiving and securing the optical ferrule 200. In some embodiments, the receiving area 20 on the first major side 101 of the unitary optical cradle 100 is a recessed area in the first major side 101 having two opposing end walls 21a, 21b and two open opposing sides 21c, 21d.

[0034] In some embodiments, the unitary optical cradle 100 is unitary molded plastic optical cradle, injection molded as a one-piece optical cradle. In some embodiments, the optical ferrule 200 is a unitary molded plastic optical ferrule, injection molded as a one-piece optical ferrule.

[0035] The unitary optical cradle 100 further includes a first light redirecting element 30 and at least one optical lightguide 40 on an opposite second major side 102 of the unitary optical cradle 100.

[0036] In some embodiments, the first light redirecting element 30 is a continuous inclined surface extending continuously across all of the optical lightguides 40 in the at least one opticallightguide 40. In some embodiments, the first light redirecting element 30 is a planer mirror. In some embodiments, the first light redirecting element 30 has a curved surface that reflects and collimates light.

[0037] In some embodiments, the first light redirecting element 30 may be interchangeably referred as “the light redirecting element 30” herein.

[0038] In some embodiments, the at least one optical lightguide 40 may include a plurality of spaced apart substantially parallel optical lightguides 40. In such cases, the at least one optical lightguide 40 may be interchangeably referred as “the plurality of optical lightguides 40” herein.

[0039] The unitary optical cradle 100 is configured to be permanently bonded to the substrate 10 with the optical lightguides 40 at least partially secured within the corresponding optical fiber-grooves 11 of the substrate 10 in one-to-one correspondence.

[0040] Now referring to FIG. 5, central light rays 51 from optical fibers 50 that are received and secured in the optical ferrule 200, enter the unitary optical cradle 100 through the receiving area 20 of the unitary optical cradle 100, are redirected by the light redirecting element 30 of the unitary optical cradle 100 from a first direction 54a to a different second direction 53 a.

[0041] The central light rays 51 entering the unitary optical cradle 100 through the receiving area 20 of the unitary optical cradle 100 are referred to as entering central light rays 56. The central light rays 51 that are redirected by the light redirecting element 30 of the unitary optical cradle 100 from the first direction 54a to the different second direction 53a are referred to as redirected central light rays 57.

[0042] Furthermore, the central light rays 51 are guided along, and substantially confined in, the optical lightguides 40 in one-to-one correspondence, exit the optical lightguides 40 from corresponding end faces 41 of the optical lightguides 40, and optically couple to the plurality of optical elements 12 of the substrate 10 in one-to-one correspondence.

[0043] The central light rays 51 guided along, and substantially confined in, the optical lightguides 40 are referred to as guided central light rays 58. Further, the central light rays 51 that optically couple to the plurality of optical elements 12 of the substrate 10 in one-to-one correspondence are referred to as optically coupled light rays 59.

[0044] In some embodiments, the central light rays 51 are redirected by the light redirecting element 30 of the unitary optical cradle 100 primarily by undergoing total internal reflection at the light redirecting element 30.

[0045] FIG. 6 is a schematic perspective view of the substrate 10 including at least one first optical fiber 13, according to an embodiment of the present disclosure. FIG. 7 is a schematic sectional front view of the substrate 10 including the at least one first optical fiber 13, according to an embodiment of the present disclosure. In some embodiments, the optical fiber 50 may be interchangeably referred as “the second optical fiber 50” herein.

[0046] Referring to FIGS. 1 to 6, the unitary optical cradle 100 is configured to be disposed on the substrate 10 so that the at least one optical lightguide 40 is at least partially disposed in the at least one first optical fiber-groove 11 in one-to-one correspondence. Further, the second optical fiber 50 is optically coupled to the optical ferrule 200 and the optical ferrule 200 is removably received and secured in the receiving area 20 of the unitary optical cradle 100.

[0047] The at least one first optical fiber-groove 11 is configured to receive the at least one first optical fiber 13 so that a first central light ray 14 from the first optical fiber 13 optically couples to the at least one first optical element 12.

[0048] In some embodiments, the at least one first optical fiber 13 may be interchangeably referred as “the plurality of first optical fibers 13” herein.

[0049] In some embodiments, the plurality of substantially parallel first optical fiber-grooves 11 is configured to receive the plurality of first optical fibers 13 in one-to-one correspondence. Further, in some embodiments, the optical fiber-grooves 11 are optically aligned with the first optical elements 12 in one-to-one correspondence, so that the first central light rays 14 from the first optical fibers 13 optically couple to the first optical elements 12 in one-to-one correspondence.

[0050] In some embodiments, the central light ray 51 may be interchangeably referred as “the second central light ray 51” herein.

[0051] The second central light ray 51 from the second optical fiber 50 sequentially enters the optical ferrule 200, is redirected for a first time by a second light redirecting element 60 of the optical ferrule 200 from a first direction 53 to a different second direction 54, exits the optical ferrule 200, and enters the unitary optical cradle 100 through the receiving area 20 of the unitary optical cradle 100, i.e., as the entering central light ray 56.

[0052] The second central light ray 51 that enters the optical ferrule 200 is referred to as an entering central light ray 51a. Further, the second central light ray 51 that is redirected for the first time by the second light redirecting element 60 is referred to as a redirected central light ray 52.

[0053] The second central light ray 51 that exits the optical ferrule 200 is referred to as an exiting central light ray 55.

[0054] The first direction 54a and the second direction 53a may be interchangeably referred as “the third direction 54a” and “the fourth direction 53a”, respectively, herein.

[0055] Furthermore, as is shown in FIG. 5, the second central light ray 51 from the second optical fiber 50 is sequentially redirected for a second time by the first light redirecting element 30 of the unitary optical cradle 100 from the third direction 54a to the different fourth direction 53a, i.e., as the redirected central light ray 57.

[0056] Furthermore, the second central light ray 51 is guided (i.e., as the guided central light ray 58) along, and substantially confined in the at least one optical lightguide 40, exits from the end face 41 of the at least one optical lightguide 40, and optically couples (i.e., as the optically coupled light ray 59) to the at least one first optical element 12.

[0057] FIG. 8 is a schematic sectional view of the substrate 10 including at least one optical lightguide 40’ having at least one first optical fiber-groove 11’, according to an embodiment of the present disclosure.

[0058] In some embodiments, the at least one optical lightguide 40 (e.g., the at least one optical lightguide 40’) has substantially a same shape as the at least one first optical fiber-groove 11 (i.e., the at least one first optical fiber-groove 11’).

[0059] In some embodiments, when the at least one optical lightguide 40’ is at least partially disposed in the at least one first optical fiber-groove 11’, the at least one optical lightguide 40’ substantially conforms to the at least one first optical fiber-groove 11’.

[0060] Referring to FIGS. 1 to 8, the optical ferrule 200 is separable from the unitary optical cradle 100 that is permanently bonded to the substrate 10. The unitary optical cradle 100 may enable compatibility with an outsourced semiconductor assembly and testing (OSAT) assembly process, such as solder-reflow compatibility, high-yield for final module assemblies, and acceptably short durations for alignment and attachment of components.

[0061] Further, the at least one optical lightguide 40 of the unitary optical cradle 100 may fit into the at least one first optical fiber-groove 11 of the substrate 10. This may provide a passivealignment, especially along a plane of the substrate 10. Therefore, an integration of the at least one optical lightguide 40 into the unitary optical cradle 100 may enhance a reliability and a yield of an attachment step of the OSAT assembly process.

[0062] Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

[0063] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and / or equivalent implementations can be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this disclosure be limited only by the claims and the equivalents thereof.

Claims

CLAIMS1. A unitary optical cradle configured to removably receive and secure an optical ferrule and be permanently bonded to a substrate that comprises at least one first optical fiber-groove optically aligned with at least one first optical element, the at least one first optical fiber-groove configured to receive at least one first optical fiber so that a first central light ray from the first optical fiber optically couples to the at least one first optical element, the unitary optical cradle comprising: a receiving area on a first major side of the unitary optical cradle, the receiving area for receiving and securing the optical ferrule; and a first light redirecting element and at least one optical lightguide on an opposite second major side of the unitary optical cradle, the unitary optical cradle configured to be disposed on the substrate so that the at least one optical lightguide is at least partially disposed in the at least one first optical fiber-groove in one-to-one correspondence, such that when a second optical fiber is optically coupled to the optical ferrule and the optical ferrule is removably received and secured in the receiving area of the unitary optical cradle, a second central light ray from the second optical fiber sequentially enters the optical ferrule, is redirected for a first time by a second light redirecting element of the optical ferrule from a first direction to a different second direction, exits the optical ferrule and enters the unitary optical cradle through the receiving area of the unitary optical cradle, is redirected for a second time by the first light redirecting element of the unitary optical cradle from a third direction to a different fourth direction, is guided along, and substantially confined in, the at least one optical lightguide, exits from an end face of the at least one optical lightguide, and optically couples to the at least one first optical element.

2. The unitary optical cradle of claim 1, being a unitary molded plastic optical cradle, injection molded as a one-piece optical cradle.

3. The unitary optical cradle of claim 1, wherein the optical ferrule is a unitary molded plastic optical ferrule, injection molded as a one-piece optical ferrule.

4. The unitary optical cradle of claim 1, wherein the at least one first optical fiber-groove is a plurality of substantially parallel first optical fiber-grooves configured to receive a plurality of first optical fibers in one-to-one correspondence, and the at least one first optical element is a plurality of first optical elements, and wherein the first optical fiber-grooves are optically aligned with the first optical elements in one-to-one correspondence, so that the first central light rays from the first optical fibers optically couple to the first optical elements in one-to-one correspondence.

5. The unitary optical cradle of claim 1, wherein the at least one first optical element comprises an optical waveguide, an optical detector, or a light emitter.

6. The unitary optical cradle of claim 1, wherein the receiving area on the first major side of the unitary optical cradle is a recessed area in the first major side having two opposing end walls and two open opposing sides.

7. The unitary optical cradle of claim 1, wherein the first light redirecting element is a continuous inclined surface extending continuously across all of the optical lightguides in the at least one optical lightguide.

8. The unitary optical cradle of claim 1, wherein the at least one optical lightguide has substantially a same shape as the at least one first optical fiber-groove, so that when the at least one optical lightguide is at least partially disposed in the at least one first optical fiber-groove, the at least one optical lightguide substantially conforms to the at least one first optical fiber-groove.

9. A unitary optical cradle comprising: a receiving area on a first major side of the unitary optical cradle for receiving and securing an optical ferrule; and a light redirecting element and a plurality of spaced apart substantially parallel optical lightguides on an opposite second major side of the unitary optical cradle, the unitary optical cradle configured to be permanently bonded to a substrate with the optical lightguides at least partially secured within corresponding optical fiber-grooves of the substrate in one-to-one correspondence, such that central light rays from optical fibers received and secured in the optical ferrule, enter the unitary optical cradle through the receiving area of the unitary optical cradle, are redirected by the light redirecting element of the unitary optical cradle from a first direction to a different second direction, are guided along, and substantially confined in, the optical lightguides in one-to-one correspondence, exit the optical lightguides from corresponding end faces of the optical lightguides, and optically couple to a plurality of optical elements of the substrate in one-to-one correspondence.

10. The unitary optical cradle of claim 9, being a unitary molded plastic optical cradle, injection molded as a one-piece optical cradle.

11. The unitary optical cradle of claim 9, wherein the optical ferrule is a unitary molded plastic optical ferrule, injection molded as a one-piece optical ferrule.

12. The unitary optical cradle of claim 9, wherein the that central light rays are redirected by the light redirecting element of the unitary optical cradle primarily by undergoing total internal reflection at the light redirecting element.

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