Method and apparatus involving digital screen generation

Claim 1

A method of reproducing an image comprising the steps of: (a) scanning an image to be reproduced; (b) generating first optical density values at selected address locations of said scanned image; (c) generating a screen cell having a selected optical density pattern with second optical density values at selected address locations, a map of said second optical density values having a sinusoidal profile; (d) repeating said screen cell in first and second directions to form a large area screen having a repetition of said second optical density values at selected address locations; (e) comparing said first and second optical density values at corresponding address locations; and (f) generating output data signals representing said comparison and defining a reproduction of said image to be reproduced.

Claim 2

A method of reproducing an image comprising the steps of: (a) scanning an image to be reproduced; (b) generating first optical density values at selected address locations of said scanned image; (c) generating a screen cell having a selected optical density pattern with second optical density values at selected address locations, a map of said second optical density values having a sinusoidal profile; (d) repeating said screen cell in first and second directions to form a large area screen having a repetition of said second optical density values at selected address locations; (e) comparing said first and second optical density values at corresponding address locations; and (f) generating output data signals representing said comparison and defining a reproduction of said image to be reproduced.

Claim 6

An apparatus for reproducing an image in raster form as a series of adjacent picture elements disposed along a plurality of adjacent parallel lines comprising: (a) scanner means for optically scanning an image to be reproduced and for generating image signals at selected address locations; (b) image sensor means operatively connected to said scanner means for generating optical density signals representing variations in the optical density of said image; (c) screen cell generating means for generating a screen cell having an optical density pattern of selected optical density values at designated address locations; (d) memory means operatively connected to said screen cell generating means for storing said optical density values at designated address locations; (e) a processor operatively connected to said memory means for incrementally addressing said memory means in steps corresponding to address differences between designated address locations of said optical density pattern; (f) comparator means operatively connected to said image sensor means and said memory means for comparing said image signals and said optical density values at corresponding address locations; and (g) output means operatively connected to and responsive to said comparator means for generating output data signals representing the image to be reproduced.

Claim 7

An apparatus for reproducing an image in raster form as a series of adjacent picture elements disposed along a plurality of adjacent parallel lines comprising: (a) scanner means for optically scanning an image to be reproduced and for generating image signals at selected address locations; (b) image sensor means operatively connected to said scanner means for generating optical density signals representing variations in the optical density of said image; (c) screen cell generating means for generating a screen cell having an optical density pattern of selected optical density values at designated address locations; (d) memory means operatively connected to said screen cell generating means for storing said optical density values at designated address locations; (e) a processor operatively connected to said memory means for incrementally addressing said memory means in steps corresponding to address differences between designated address locations of said optical density pattern; (f) comparator means operatively connected to said image sensor means and said memory means for comparing said image signals and said optical density values at corresponding address locations; and (g) output means operatively connected to and responsive to said comparator means for generating output data signals representing the image to be reproduced.

Claim 9

A method of reproducing an image comprising the steps of: (a) scanning an image to be reproduced; (b) generating first optical density values at selected address locations of said scanned image; (c) generating a screen cell having a selected optical density pattern with second optical density values at selected address locations; (d) storing said second optical density values in a memory array having address locations corresponding to said address locations of said scanned image; (e) subdividing said screen cell into a screen cell matrix having a series of parallel lines, selected points along each of said lines having a unique address location, certain ones of said parallel lines being in a first direction and certain other ones of said lines being in a second direction; (f) incrementally addressing said memory array in steps representing an address difference between selected ones of said points and an address difference between selected ones of said parallel lines; (g) repeating said screen cell in first and second directions to form a large area screen having a repetition of said second optical density values at selected address locations; (h) comparing said first and second optical density values at corresponding address locations; and (i) generating output data signals representing said comparison and defining a reproduction of said image to be reproduced.

Claim 10

A method of reproducing an image comprising the steps of: (a) scanning an image to be reproduced; (b) generating first optical density values at selected address locations of said scanned image; (c) generating a screen cell having a selected optical density pattern with second optical density values at selected address locations; (d) storing said second optical density values in a memory array having address locations corresponding to said address locations of said scanned image; (e) subdividing said screen cell into a screen cell matrix having a series of parallel lines, selected points along each of said lines having a unique address location, certain ones of said parallel lines being in a first direction and certain other ones of said lines being in a second direction; (f) incrementally addressing said memory array in steps representing an address difference between selected ones of said points and an address difference between selected ones of said parallel lines; (g) repeating said screen cell in first and second directions to form a large area screen having a repetition of said second optical density values at selected address locations; (h) comparing said first and second optical density values at corresponding address locations; and (i) generating output data signals representing said comparison and defining a reproduction of said image to be reproduced.

Claim 11

A method of reproducing an image comprising the steps of: (a) scanning an image to be reproduced; (b) generating first optical density values at selected address locations of said scanned image; (c) generating a screen cell having a selected optical density pattern with second optical density values at selected address locations; (d) storing said second optical density values in a memory array having address locations corresponding to said address locations of said scanned image; (e) subdividing said screen cell into a screen cell matrix having a series of parallel lines, selected points along each of said lines having a unique address location, certain ones of said parallel lines being in a first direction and certain other ones of said lines being in a second direction; (f) incrementally addressing said array memory in said first direction in steps representing an address difference between selected ones of said points and an address difference between selected ones of said parallel lines and in said second direction in steps representing an address difference between selected ones of said points and an address difference between selected ones of parallel lines; (g) repeating said screen cell in first and second directions to form a large area screen having a repetition of said second optical density values at selected address locations; (h) comparing said first and second optical density values at corresponding address locations; and (i) generating output data signals representing said comparison and defining a reproduction of said image to be reproduced.

Claim 12

A method of reproducing an image comprising the steps of: (a) scanning an image to be reproduced; (b) generating first optical density values at selected address locations of said scanned image; (c) generating a screen cell having a selected optical density pattern with second optical density values at selected address locations; (d) storing said second optical density values in a memory array having address locations corresponding to said address locations of said scanned image; (e) subdividing said screen cell into a screen cell matrix having a series of parallel lines, selected points along each of said lines having a unique address location, certain ones of said parallel lines being in a first direction and certain other ones of said lines being in a second direction; (f) incrementally addressing said array memory in said first direction in steps representing an address difference between selected ones of said points and an address difference between selected ones of said parallel lines and in said second direction in steps representing an address difference between selected ones of said points and an address difference between selected ones of parallel lines; (g) repeating said screen cell in first and second directions to form a large area screen having a repetition of said second optical density values at selected address locations; (h) comparing said first and second optical density values at corresponding address locations; and (i) generating output data signals representing said comparison and defining a reproduction of said image to be reproduced.

Claim 13

A method of generating a digital screen for reproducing an image in raster form as a series of adjacent picture elements disposed along a plurality of adjacent lines, said method comprising the steps of: (a) generating a screen cell having a selected optical density pattern with selected optical density values at designated address locations; (b) subdividing said screen cell into a screen cell matrix characterized by a series of parallel lines, selected points along each said line having unique address locations; (c) storing said screen cell in a memory array at address locations corresponding to said designated address locations; and (d) incrementally addressing said memory array in steps representing an address difference between selected ones of said points and an address difference between selected ones of said lines, said memory array being incrementally addressed in a first direction in steps representing an address difference between selected ones of said points and an address difference between selected ones of said parallel lines and in a second direction in steps representing an address difference between selected ones of said points and an address difference between selected ones of said parallel lines.

Claim 14

A method of generating a digital screen for reproducing an image in raster form as a series of adjacent picture elements disposed along a plurality of adjacent lines, said method comprising the steps of: (a) generating a screen cell having a selected optical density pattern with selected optical density values at designated address locations; (b) subdividing said screen cell into a screen cell matrix characterized by a series of parallel lines, selected points along each said line having unique address locations; (c) storing said screen cell in a memory array at address locations corresponding to said designated address locations; and (d) incrementally addressing said memory array in steps representing an address difference between selected ones of said points and an address difference between selected ones of said lines, said memory array being incrementally addressed in a first direction in steps representing an address difference between selected ones of said points and an address difference between selected ones of said parallel lines and in a second direction in steps representing an address difference between selected ones of said points and an address difference between selected ones of said parallel lines.