Methods and systems for fabrication of shaped fiber elements for scanning fiber displays
A fiber optic element of a fiber scanning system includes a motion actuator having longitudinal side members, an internal orifice, a first support region, a central region, and a second support region. The fiber optic element also includes a first fiber optic cable passing through the internal orifice and having a first fiber joint as well as a second fiber optic cable passing through the internal orifice. The second fiber optic cable has a second fiber joint disposed in the central region and spliced to the first fiber joint, a second coupling region, a light delivery region, and a light emission tip. The light delivery region is characterized by a first diameter and the light emission tip is characterized by a second diameter less than the first diameter.
1. A method of fabricating a shaped fiber, the method comprising:
providing a fiber optic cable;
covering a portion of the fiber optic cable with an etch jacket to define an exposed region of the fiber optic cable and a covered region of the fiber optic cable;
exposing the exposed region of the fiber optic cable and the etch jacket to an etchant solution;
removing at least a portion of the exposed region of the fiber optic cable in response to exposure to the etchant solution; and
wicking the etchant solution under at least a portion of the etch jacket to remove at least a portion of the covered region of the fiber optic cable.
2. The method of claim 1 wherein wicking the etchant solution under the etch jacket comprises capillary flow of the etchant solution.
3. The method of claim 1 wherein the etch jacket comprises a proximal section adjacent the exposed region of the fiber optic cable and a reentrant profile is formed adjacent the proximal section.
4. The method of claim 3 wherein the fiber optic cable is characterized by a first diameter at a first longitudinal position of the covered region and a second diameter greater than the first diameter at a second longitudinal position closer to the exposed region than the first longitudinal position.
5. The method of claim 1 wherein the etchant solution comprises buffered oxide etch (BOE).
6. The method of claim 1 further comprising:
removing the etch jacket;
covering the covered region of the fiber optic cable with a second etch jacket;
exposing the exposed region of the fiber optic cable and the second etch jacket to a second etchant solution; and
forming a tapered profile in the exposed region of the fiber optic cable.
7. The method of claim 6 wherein the tapered profile is characterized by a first diameter at a first longitudinal position of the exposed region and a second diameter less than the first diameter at a second longitudinal position farther from the covered region than the first longitudinal position.
8. The method of claim 6 wherein the etchant solution and the second etchant solution are a same etchant solution.
9. A method of fabricating a tapered fiber emission tip, the method comprising:
providing a fiber optic cable having an emission region and an emission face;
coating the emission region and the emission face with an etch resistant mask;
removing a portion of the etch resistant mask to expose a portion of the emission region adjacent the emission face and form a sidewall mask and a separate emission face mask;
providing an etch solution;
inserting the emission region into the etch solution;
etching a portion of the emission region to form successively deeper etch profiles;
determining an etch endpoint; and
removing the emission region from the etch solution.
10. The method of claim 9 wherein determining an etch endpoint comprises detecting separation of the separate emission face mask from the emission face.
11. The method of claim 10 wherein determining an etch endpoint further comprises using a machine vision system to monitor the separation of the separate emission face mask from the emission face.
12. The method of claim 9 wherein the sidewall mask and the separate emission face mask are separated by a spatial separation having a predefined length.
13. The method of claim 12 wherein a distal portion of the spatial separation is aligned with the emission face.
14. The method of claim 9 wherein the portion of the emission region is characterized by a tapered profile.
15. The method of claim 14 wherein the tapered profile is characterized by a first diameter at a first longitudinal position of the emission region and a second diameter less than the first diameter at a second longitudinal position closer to the emission face than the first longitudinal position.
16. The method of claim 15 wherein the etch endpoint is associated with a diameter of fiber optic cable being reduced to zero at the emission face.
17. The method of claim 9 wherein etching a portion of the emission region to form successively deeper etch profiles comprises wicking the etch solution under at least a portion of the sidewall mask.
18. The method of claim 17 further comprising removing at least a portion of the fiber optic cable covered by the sidewall mask.
19. The method of claim 9 further comprising wicking the etch solution under at least a portion of the separate emission face mask.
20. The method of claim 9 wherein the emission face is characterized by a face diameter and the separate emission face mask is characterized by a mask diameter less than the face diameter.