Monolithic two-dimensional optical fiber array
A two-dimensional (2D) optical fiber array component takes the form of a (relatively inexpensive) fiber guide block that is mated with a precision output element. The guide block and output element are both formed to include a 2D array of through-holes that exhibit a predetermined pitch. The holes formed in the guide block are relatively larger than those in precision output element. A loading tool is used to hold a 1×N array of fibers in a fixed position that exhibits the desired pitch. The loaded tool (holding the pre-aligned 1×N array of fibers) is then inserted through the aligned combination of the guide block and output element, and the fiber array is bonded to the guide block. The tool is then removed, re-loaded, and the process continued until all of the 1×N fiber arrays are in place. By virtue of using a precision tool to load the fibers, the guide block does not have to be formed to exhibit precise through-hole dimensions, allowing for a relatively inexpensive guide block to be used.
1. A two-dimensional (2D) array component for supporting a plurality of individual optical fibers in a 2D configuration exhibiting a predetermined pitch, the array component comprising:
a non-precision fiber guide block including a plurality of through-holes arranged in a 2D array configuration exhibiting the predetermined pitch, the plurality of through-holes formed to guide fibers passing therethrough and reduce pointing error, with each through-hole having a first diameter sufficient to accommodate a coated optical fiber;
a silicon-based output element including a plurality of vias etched through a thickness of the silicon-based output element, the plurality of etched vias arranged in the 2D array configuration exhibiting the predetermined pitch, each etched via having a second diameter less than the first diameter, the second diameter on the order of a cladded optical fiber; and
a mounting flange for supporting the fiber guide block and the silicon-based output element in an aligned configuration such that the 2D array component exhibits a pitch error no greater than ±1 μm and a pointing error no greater than ±15 mrad.
2. The 2D array component as defined in claim 1 wherein the silicon-based output element comprises a multilayer structure of multiple silicon layers.
3. The 2D array component as defined in claim 2 wherein the multilayer structure silicon-based output element comprises
an output silicon layer including a first plurality of etched vias arranged in the 2D array configuration exhibiting the predetermined pitch, each etched via formed to exhibit the first diameter; and
an input silicon layer including a second plurality of etched vias arranged in the 2D array configuration, the input silicon layer positioned in alignment with the output silicon layer such that the second plurality of etched vias aligns with the first plurality of etched vias.
4. The 2D array component as defined in claim 3 wherein each etched via of the first and second pluralities of etched vias includes a larger lead-in opening to facilitate the insertion of optical fibers.
5. The 2D array component as defined in claim 3 wherein the multilayer structure silicon-based output element further comprises
a silicon spacer disposed between the output and input silicon layers, the silicon spacer including a plurality of relief holes disposed in a 2D array pattern that aligns with the first and second pluralities of etched vias formed in the output and input silicon layers.
6. The 2D array component as defined in claim 5 wherein the silicon spacer is formed to have a thickness t selected to minimize pointing error in the 2D array component.
7. The 2D array component as defined in claim 3 wherein the diameter of the etched vias formed in the input silicon layer is greater than the first diameter associated with the etched vias formed in the output silicon layer.
8. The 2D array component as defined in claim 1 wherein the mounting flange includes a central sleeve for engaging the fiber guide block and the silicon-based output element, the central sleeve including a first shoulder rim for supporting the fiber guide block and a second shoulder rim for supporting the silicon-based output element with a predefined gap spacing g between the first and second shoulder rims.
9. The 2D array component as defined in claim 1 wherein the non-precision fiber guide block is formed of a plastic material.
10. The 2D array component as defined in claim 9 wherein the non-precision fiber guide block comprises a molded plastic material component.