Integrated sensor and lens assembly with post-tuning optical alignment
An integrated image sensor and lens assembly may include a lens barrel, a collet, and a lens mount. The lens barrel may be coupled to the collet which is coupled to the lens mount. The lens barrel and the collet may each include a fastening structure reciprocal to each other. Alternatively, the collet and the lens mount may each include a fastening structure reciprocal to each other. The optical distance between the set of lenses and the image sensor may be tuned such that the focal plane of the lenses coincides with the image plane. The fastening structures allow the lens barrel to be adjusted relative to the lens mount in order to shift the focal plane in a direction along the optical axis to compensate for focal shifts occurring during assembly/cure and/or temperature cycling.
1. A method of manufacturing an integrated image sensor and lens assembly comprising:
positioning a collet within a channel of a tube portion of a lens mount, the lens mount affixed to an image sensor substrate comprising an image sensor;
positioning a lens barrel within the collet, the lens barrel housing a set of lenses for directing light to the image sensor, the lens barrel having threads on an exterior surface of the lens barrel that mate with threads on an interior surface of the collet, wherein rotation of the lens barrel within the collet causes a change in vertical alignment of the lens barrel;
checking an alignment of an optical axis and a focal plane;
aligning the lens barrel, the collet, and the lens mount such that the optical axis is substantially perpendicular to the focal plane and the focal plane is aligned with the image sensor;
adhering the collet to the tube portion of the lens mount using an adhesive;
curing the adhesive to affix the collet within the tube portion of the lens mount;
after curing the adhesive, re-checking alignment of the optical axis and the focal plane; and
rotating the lens barrel in the collet in a direction such that the focal plane is re-aligned with the image sensor.
2. The method of claim 1 , further comprising:
after the focal plane is re-aligned with the image sensor, affixing the lens barrel to the collet via a second adhesive.
3. The method of claim 1 , wherein the lens mount includes a base portion, the tube portion having a channel and extending from the base portion in a direction of an optical axis substantially perpendicular to a focal plane.
4. The method of claim 1 , wherein the collet comprises a body extending into the channel of the tube portion and the collet comprises a first fastening structure.
5. The method of claim 4 , wherein the lens barrel includes a first portion extending into the body of the collet and the lens barrel comprises a second fastening structure reciprocal to the first fastening structure.
6. The method of claim 5 , wherein the lens barrel is mounted to the collet via the first fastening structure and the second fastening structure.
7. The method of claim 5 , wherein the first fastening structure and the second fastening structure are configured to allow the lens barrel to move relative to the lens mount and to cause a shift in the focal plane in a direction along the optical axis.
8. The method of claim 5 , wherein the first fastening structure and the second fastening structure are configured to maintain a position of the optical axis substantially perpendicular to the focal plane.
9. The method of claim 5 , wherein the first portion of the lens barrel is tapered and the body of the collet comprises an interior lip configured to retain a fluid and to prevent the fluid from being deposited onto the image sensor.
10. The method of claim 9 , wherein the fluid is viscous non-curing fluid.
11. The method of claim 4 , wherein the first fastening structure is on an inner surface of the body of the collet.
12. The method of claim 1 , further comprising:
providing the integrated image sensor and lens assembly within a camera; and
coupling a lens ring to the lens barrel external to a body of the camera.
13. The method of claim 12 , further comprising:
providing an input mechanism to control the camera to capture an image corresponding to the light directed to the image sensor.