Digital camera incorporating high frame rate mode

Claim 1

A method of reading out a CCD interline image sensor having M lines×N columns of photosites, N vertical shift registers corresponding to said N columns of photosites and a horizontal shift register coupled to said N vertical shift registers, comprising the steps of: configuring said sensor to include first, second, and third sets of contiguous lines of photosites inclusive of all of said M lines of photosites; wherein the number of lines in said first and third sets are substantially equal; exposing said sensor to a first frame such that all of said M lines of photosites are exposed; transferring all of said M lines of photosites to said N vertical shift registers; serially shifting each line of data from said N vertical shift register and reading out said horizontal shift register until all of said lines of data of said first and second sets of contiguous lines have been read out, wherein said third set of lines have not been read out of said vertical shift registers; exposing said sensor to a second frame such that all of said M lines of photosites are exposed; transferring all of said M lines of photosites to said N vertical shift registers such that the first set of lines of photosites of said second frame are accumulated with said third set of lines of photosites of said first frame; and repeating said serially shifting step; wherein said frame rate of said sensor is increased by a factor of the number of lines in said first and second sets divided by M lines of said sensor.

Claim 2

A method of reading out a CCD interline image sensor having M lines×N columns of photosites, N vertical shift registers corresponding to said N columns of photosites and a horizontal shift register coupled to said N vertical shift registers, comprising the steps of: configuring said sensor to include first, second, and third sets of contiguous lines of photosites inclusive of all of said M lines of photosites; wherein the number of lines in said first and third sets are substantially equal; exposing said sensor to a first frame such that all of said M lines of photosites are exposed; transferring all of said M lines of photosites to said N vertical shift registers; serially shifting each line of data from said N vertical shift register and reading out said horizontal shift register until all of said lines of data of said first and second sets of contiguous lines have been read out, wherein said third set of lines have not been read out of said vertical shift registers; exposing said sensor to a second frame such that all of said M lines of photosites are exposed; transferring all of said M lines of photosites to said N vertical shift registers such that the first set of lines of photosites of said second frame are accumulated with said third set of lines of photosites of said first frame; and repeating said serially shifting step; wherein said frame rate of said sensor is increased by a factor of the number of lines in said first and second sets divided by M lines of said sensor.