Focus stabilization of imaging system with variable focus lens

1. A computer-implemented method for focus stabilization of an imaging system, the method comprising:

obtaining, by a processor, a calibration parameter value;

obtaining, by the imaging system, a first plurality of images of an object of interest, wherein each image of the first plurality of images is obtained by the imaging system at a different optical focus;

identifying, by the processor, a region of interest in at least one image of the first plurality of images, wherein the region of interest contains an indicia indicative of the object of interest;

analyzing, by the processor, each of the images of the first plurality of images at the region of interest;

determining, by the processor, a set of image quality values from the analyzed images, wherein each of the image quality values of the set of image quality values corresponds to a respective analyzed image in the first plurality of images;

determining, by the processor, a current alignment parameter value from at least one of the image quality values of the set of image quality values;

determining, by the processor, a tuning parameter value by comparing the alignment parameter value with the calibration parameter value; and

tuning, by the processor, the imaging system according to the tuning parameter.

2. The method of claim 1 , wherein obtaining the calibration parameter value comprises obtaining, by the processor, the calibration parameter value from at least one of a memory, network, cloud network, wireless communication, or wired communication.

3. The method of claim 1 , wherein obtaining the calibration parameter value comprises:

obtaining, by the imaging system, a plurality of calibration images of an object of interest, wherein each image of the plurality of calibration images is obtained by the imaging system at a different optical focus;

identifying, by the processor, a region of interest in at least one image of the plurality of calibration images, wherein the region of interest contains an indicia indicative of the object of interest;

analyzing, by the processor, each of the images of the plurality of calibration images at the region of interest;

determining, by the processor, a set of calibration image quality values from the analyzed images, wherein each of the calibration image quality values of the set of calibration image quality values corresponds to a respective image in the plurality of calibration images; and

determining, by the processor, a calibration parameter value from at least one of the calibration image quality values of the set of calibration image quality values.

4. The method of claim 3 , wherein obtaining the plurality of calibration images comprises obtaining a first image at a first optical focus, a second image at a second optical focus that is greater than the first optical focus, and a third image at a third optical focus that is greater than the second; and

wherein obtaining the first plurality of images comprises obtaining a first image at a first optical focus, a second image at a second optical focus that is greater than the first optical focus, and a third image at a third optical focus that is greater than the second optical.

5. The method of claim 4 , wherein the calibration parameter is determined by a ratio of the image quality values of the first image and third image of the plurality of calibration images; and

the current alignment parameter value is determined by a ratio of the image quality values of the first image and third image of the first plurality of images.

6. The method of claim 4 , wherein the calibration parameter value comprises a ratio between at least two of the image quality values of the set of calibration image quality values; and

the current alignment parameter value comprises a ratio between at least two of the image quality values of the set of image quality values of the first plurality of images.

7. The method of claim 1 , wherein the calibration parameter value comprises at least one of a sharpness value, a contrast value, or a spatial frequency content value.

8. The method of claim 1 , wherein the current alignment parameter value at least one of an image sharpness value, a contrast value, or a spatial frequency content value.

9. The method of claim 1 , wherein tuning the optical focus of the imaging system comprises tuning the focal distance of a variable focus lens by applying an operating voltage to the variable focus lens.

10. The method of claim 9 , wherein the variable focus lens is one of a T-lens or a liquid lens.

11. The method of claim 1 , wherein obtaining the first plurality of images comprises:

obtaining a first image by obtaining a plurality of frames at a first optical focus;

obtaining a second image by obtaining a plurality of frames at a second optical focus;

obtaining a third image by obtaining a plurality of frames at a third optical focus; and

wherein identifying a region of interest in at least one image of the first plurality of images comprises identifying, by the processor, a region of interest in at least of the first image, second image, and third image of the first plurality of images.

12. The method of claim 1 , further comprising:

identifying, by the processor, the indicia in the region of interest, with the indicia having a decodable payload.

13. A focus stabilization imaging system comprising:

a variable focus lens configured to receive light from an object of interest for imaging the object of interest;

a controller communicatively coupled to the variable focus lens and configured to provide a voltage to the variable focus lens;

an imaging sensor configured to receive an image of the object and to generate an electrical signal indicative of the received image;

a processor and computer-readable media storing machine readable instructions that, when executed, cause the focus stabilization imaging system to:

obtain, by the processor, a calibration parameter value;

obtain, by the imaging system, a first plurality of images of the object of interest, wherein each image of the first plurality of images is obtained by the imaging system at a different optical focus;

identify, by the processor, a region of interest in at least one image of the first plurality of images, wherein the region of interest contains an indicia indicative of the object of interest;

analyze, by the processor, each of the images of the first plurality of images at the region of interest;

determine, by the processor, a set of image quality values from the analyzed images, wherein each of the image quality values of the set of image quality values corresponds to a respective analyzed image in the first plurality of images;

determine, by the processor, a current alignment parameter value from at least one of the image quality values of the set of image quality values;

determine, by the processor, a tuning parameter value by comparing the current alignment parameter value with the calibration parameter value; and

tune, by the controller, the optical focus of the imaging system according to the tuning parameter.

14. The focus stabilization imaging system of claim 13 , wherein obtaining the calibration parameter value comprises obtaining, by the processor, the calibration parameter value from at least one of a memory, network, cloud network, wireless communication, or wired communication.

15. The focus stabilization imaging system of claim 13 , wherein obtaining the calibration parameter value comprises:

obtaining, by the imaging system, a plurality of calibration images of an object of interest, wherein each image of the plurality of calibration images is obtained by the imaging system at a different optical focus;

identifying, by the processor, a region of interest in at least one image of the plurality of calibration images, wherein the region of interest contains an indicia indicative of the object of interest;

analyzing, by the processor, each of the images of the plurality of calibration images at the region of interest;

determining, by the processor, a set of calibration image quality values from the analyzed images, wherein each of the calibration image quality values of the set of calibration image quality values corresponds to a respective image in the plurality of calibration images; and

determining, by the processor, a calibration parameter value from at least one of the calibration image quality values of the set of calibration image quality values.

16. The method of claim 15 , wherein obtaining the plurality of calibration images comprises obtaining a first image at a first optical focus, a second image at a second optical focus that is greater than the first optical focus, and a third image at a third optical focus that is greater than the second; and

wherein obtaining the first plurality of images comprises obtaining a first image at a first optical focus, a second image at a second optical focus that is greater than the first optical focus, and a third image at a third optical focus that is greater than the second optical.

17. The method of claim 16 , wherein the calibration parameter is determined by a ratio of the image quality values of the first image and third image of the plurality of calibration images; and

the current alignment parameter value is determined by a ratio of the image quality values of the first image and third image of the first plurality of images.

18. The method of claim 16 , wherein the calibration parameter value comprises a ratio between at least two of the image quality values of the set of calibration image quality values; and

the current alignment parameter value comprises a ratio between at least two of the image quality values of the set of image quality values of the first plurality of images.

19. The method of claim 13 , wherein the calibration parameter value comprises at least one of a sharpness value, a contrast value, or a spatial frequency content value.

20. The method of claim 13 , wherein the current alignment parameter value at least one of an image sharpness value, a contrast value, or a spatial frequency content value.

21. The method of claim 13 , wherein tuning the optical focus of the imaging system comprises tuning the focal distance of a variable focus lens by applying an operating voltage to the variable focus lens.

22. The method of claim 21 , wherein the variable focus lens is one of a T-lens or a liquid lens.

23. The method of claim 13 , wherein obtaining the first plurality of images comprises:

obtaining a first image by obtaining a plurality of frames at a first optical focus;

obtaining a second image by obtaining a plurality of frames at a second optical focus;

obtaining a third image by obtaining a plurality of frames at a third optical focus; and

wherein identifying a region of interest in at least one image of the first plurality of images comprises identifying, by the processor, a region of interest in at least of the first image, second image, and third image of the first plurality of images.

24. The method of claim 13 , further comprising:

identifying, by the processor, the indicia in the region of interest, with the indicia having a decodable payload.