Method and apparatus for focus correction of multi-image laser beam quality measurements

A method for correcting the focus of an image, comprising:

• providing at least one imaging device including at least one image sensor configured to capture one or more images of one or more scattered light signals scattered from at least one light beam propagating through at least one sampling region;
• determining at least one location of at least one focal plane of at least one optical beam analysis system having at least one in-focus modulation transfer function H(ξ) using at least one imaging device;
• determining at least one out-of-focus transfer function G(ξ,d) for at least one out-of-focus image using at least one image processing module;
• capturing the out-of-focus image of the scattered light signal with the imaging device;
• determining at least one first axis of the out-of-focus image with the image processing module;
• dividing the image into one or more slices along at least one projection of the first axis of the out-of-focus image, each the slice having at least one center location;
• calculating at least one distance, d, from the center location of the each slice to the focal plane corresponding to each slice;
• using the distance, d, to resolve the out-of-focus transfer function G(ξ,d) for each slice;
• deconvolving each slice of the image against the in-focus modulation transfer function H(ξ) and the out-of-focus transfer function G(ξ,d);
• and
• outputting at least one corrected image to at least one display.