Optical component plastic deformation control process
View Patent ↗A process for aligning an optical component by plastic deformation comprises finding a desired position of an optical axis of the optical component relative to a rest position of the optical axis of the optical component. Then, a deformation force is exerted, which is greater than a yield force of the optical component to thereby plastically deform the optical component in a direction of the desired position. The alignment process addresses mechanical compliance in the alignment system and/or optical system during the plastic deformation of optical components of the optical system. This mechanical compliance arises from the fact that there is typically flexing in the alignment system between the encoders and the part of the alignment system that actually engages the optical component.
1. A process for aligning an optical component by plastic deformation, the process comprising:
finding a desired position of on optical axis of the optical component relative to a rest position of the optical axis of the optical component by moving the optical axis of the optical component along a path that extends in a circuit around the rest position, the path extending in an x-y plane that is orthogonal to the optical axis of the optical component;
determining a direction of the desired position; and
exerting a deformation force that exceeds a yield force to plastically deform the optical component so that the optical axis is in the direction of the desired position;
wherein the rest position is found after the desired position is found to account for any plastic deformation induced during the step of finding the desired position.
2. A process as claimed in claim 1 , further comprising avoiding backlash by not deforming the optical component such that a new rest position of the optical axis is opposed the desired position with respect to a previous rest position in a plane that is orthogonal to the optical axis.
3. A process as claimed in claim 1 , further comprising monitoring an active alignment signal while exerting the deformation force.
4. A process as claimed in claim 3 , further comprising comparing the active alignment signal to a level of the active alignment signal when the optical component was at the desired position.
5. A process as claimed in claim 1 , wherein the step of finding the desired position of the optical axis of the optical component comprises monitoring an active alignment signal while moving the optical axis of the optical component.
6. A process as claimed in claim 5 , wherein the optical component includes an optical fiber having an endface and a deformable mounting structure that supports the optical fiber on an optical bench, and wherein the step of monitoring the active alignment signal comprises:
generating and coupling an optical signal into the optical fiber;
detecting a level of backreflection of the optical signal into the optical fiber through the endface as the active alignment signal.
7. A process as claimed in claim 6 , wherein the step of finding the desired position further comprises positioning the optical component to maximize a level of the backreflection.
8. A process as claimed in claim 6 , further comprising monitoring the active alignment signal while exerting the deformation force to assess the plastic deformation of the optical component.
9. A process as claimed in claim 5 , wherein the optical component includes an optical fiber having an endface and a deformable mounting structure that supports the optical fiber on an optical bench, and wherein the step of monitoring the active alignment signal comprises:
generating an optical signal by energizing an active device on the optical bench; and
detecting a level of the optical signal that is coupled into the optical fiber through the endface as the active alignment signal.
10. A process as claimed in claim 9 , wherein the step of finding the desired position further comprises positioning the optical component to maximize a level of the active alignment signal.
11. A process as claimed in claim 9 , further comprising monitoring the active alignment signal while exerting the deformation force to assess the plastic deformation of the optical component.
12. A process as claimed in claim 1 , wherein the step of moving the optical axis of the optical component along a path around the rest position comprising dithering the optical axis of the optical component.
13. A process for aligning an optical component by plastic deformation, the process comprising:
finding a desired position of an optical axis of the optical component relative to a rest position of the optical axis of the optical component by moving the optical axis of the optical component alon a loo that extends in an x-y plane that is orthogonal to the optical axis of the optical component;
exerting a deformation force that exceeds a yield force to plastically deform the optical component so that the optical axis is moved in a direction of the desired position;
monitoring an active alignment signal while exerting the deformation force;
comparing the active alignment signal to a level of the active alignment signal when the optical component was at the desired position; and
finding a new desired position relative to a new rest position, if a level of the active signal detected while exerting the deformation force is less than the level of the active alignment signal when the optical component was at the desired position by a predetermined tolerance.
14. A process for aligning an optical component by plastic deformation, the process comprising:
finding a desired position of an optical axis of the optical component relative to a rest position of the optical axis of the optical component by moving the optical axis of the optical component along a oath that extends in an x-y plane that is orthogonal to the optical axis of the optical component;
exerting a deformation force that exceeds a yield force to plastically deform the optical component so that the optical axis is moved in a direction of the desired position;
wherein the step of finding the desired position of the optical axis of the optical component comprises monitoring an active alignment signal while moving the optical axis of the optical component; and
wherein the optical component includes an optical element and a deformable mounting structure that supports the optical element on an optical bench, and wherein the step of monitoring the active alignment signal comprises:
transmitting an optical signal to the optical element;
detecting the optical signal after interaction with the optical element;
spectrally analyzing the optical signal for side mode suppression; and
using the side mode suppression as the active alignment signal.
15. A process as claimed in claim 14 wherein the step of finding the desired position further comprises positioning the optical component to maximize the level of the side mode suppression.
16. A process as claimed in claim 14 , further comprising monitoring the active alignment signal while exerting the deformation force to assess the plastic deformation of the optical component.