Pixel multiplication using code spread functions

摘要

Methods and apparatus for pixel multiplication in optical imaging systems. In one example, an expanded optical point spread function, referred to as a code spread function, is used to phase modulate an incident electromagnetic wavefront, and digital processing, including correlation techniques, are used to filter and process the modulated wavefront to recover sub-pixel information from an image produced by the wavefront on a pixilated detector array.

主权项

1. A method of pixel multiplication in an optical imaging system comprising:
receiving a wavefront of electromagnetic radiation at an entrance aperture of the optical imaging system; propagating the wavefront to a pupil plane of the optical imaging system; modulating the wavefront at the pupil plane with a modulation pattern based on a predetermined code spread function for the optical imaging system to produce a modulated wavefront; propagating the modulated wavefront to an imaging detector which includes an array of detector pixels, each pixel having a pixel width; sampling the modulated wavefront at the imaging detector to produce a sampled data set; and digitally processing the sampled data set the produce an image, the digital processing including:
replicating the sampled data set to produce at least four sampled data sets;individually filtering the at least four sampled data sets in parallel with corresponding digital correlation filters each having a filter function based on a shifted code spread function pattern corresponding to a half pixel width relative shift of the predetermined code spread function on the imaging detector to produce at least four filtered data sets; andinterleaving the at least four filtered data sets to produce the image.