Fiber alignment using a channel incorporating a fulcrum structure
View Patent ↗Optical alignment between a communication optical fiber and an optical device is achieved by using a substrate including a fiber-holding channel formed in the top surface of the substrate. The channel is particularly formed to include a central fulcrum region, against which the fiber is pressed into as the fiber-to-device alignment is performed. In particular, the fulcrum functions as a pivot point to allow for the free endface of the fiber nearest the optical device to be adjusted (performing a “fine” adjustment) by manipulating the opposing end of the fiber (using a “gross” movement) until alignment with the optical device is achieved. A reduction of, for example, 14:1 between the gross movement and the fine adjustment can be achieved by using the inventive fulcrum structure.
1. A support element for facilitating optical alignment between an endface of an optical communication fiber and an optical device, the support element comprising
a substrate, including a top major surface, with a fiber channel formed along a predetermined longitudinal extent, defined as the z-axis, of said top major surface; and
a fulcrum disposed along a central portion of said channel, said fulcrum for supporting an optical fiber positioned along said channel and functioning as a pivot point to allow for relative motion of the endface of said fiber in the x-y plane as said fiber remains pressed into said fulcrum so as to provide x-y direction alignment between said fiber endface and an associated optical device.
2. The support element as defined in claim 1 wherein the support element further comprises
a coverplate disposed to contact the substrate top major surface and enclose an associated communication fiber between said coverplate and said substrate.
3. The support element as defined in claim 1 wherein the element further comprises an epoxy adhesive used to fix the communication fiber to the fulcrum and channel once alignment is achieved.
4. The support element as defined in claim 1 wherein the element further comprises a solder adhesive used to fix the communication fiber to the fulcrum and channel once alignment is achieved.
5. The support element as defined in claim 1 wherein the substrate comprises silicon.
6. The support element as defined in claim 1 wherein the fiber channel comprises a V-groove structure.
7. The support element as defined in claim 6 wherein the V-groove structure comprises an etched V-groove.
8. A support element for facilitating optical alignment between a plurality of N optical communication fibers and one or more optical devices, the support element comprising
a substrate, including a top major surface, with a plurality of N fiber channels formed at predetermined locations across said substrate top major surface in a defined z-axis direction; and
a plurality of N fulcrums, each disposed along a central portion of an associated fiber channel, each fulcrum for supporting a separate one of the plurality of N optical fibers and functioning as a pivot point to allow for relative motion in the x-y plane of an endface of said fiber as said fiber remains pressed into said fulcrum so as to provide x-y direction alignment between said fiber and an associated optical device.
9. A support element as defined in claim 8 wherein the support element further comprises a coverplate so as to enclose the plurality of N channels.
10. A support element as defined in claim 8 wherein the support element further comprises a plurality of N coverplates, each coverplate disposed to cover a separate one of the plurality of N channels formed in the substrate.
11. A support element as defined in claim 8 wherein the substrate comprises silicon and the plurality of N channels comprise a plurality of N V-grooves.
12. A method of providing optical alignment between an optical communication fiber and an active optical device, the method comprising the steps of:
providing an alignment element including a longitudinally disposed channel, defined as the z-axis, with a fulcrum structure disposed along a central region of said channel;
positioning an optical fiber along said channel such that said fiber is pressed against only the fulcrum structure, a first end of said fiber for coupling light into and out of an associated active optical device and a second end extending out beyond said alignment element;
using said fulcrum as a pivot point, moving the second end of said fiber in the x and y directions to adjust the position of said first end so as to provide alignment between said first end of said fiber and said active optical device.
13. The method as defined in claim 12 wherein prior to positioning the optical fiber along the channel, the following step is performed:
imparting a bend along a predetermined section of the optical communication fiber, said bend functioning to apply a downward bias force along said fiber into the fulcrum structure of the channel.
14. The method as defined in claim 12 wherein the method further comprises the step of:
forming a lensed endface along the first end of the optical communication fiber.
15. The method as defined in claim 12 wherein the method further comprises the steps of:
fixing the aligned fiber to the channel and the fulcrum; and
positioning a coverplate over the substrate so as to enclose said substrate.
16. The method as defined in claim 15 , wherein in performing the fixing steps, an epoxy is used to form the attachments.
17. The method as defined in claim 15 , wherein in performing the fixing steps, a solder is used to form the attachments.