04278755 is referenced by 3 patents and cites 8 patents.

An improved halftone dot screen for use in reproduction of continuous-tone graphic images is disclosed. The screen comprises a two-dimensional matrix of cells (dots) each cell having a common pattern of transmittance to radiation utilized in the reproduction process. The common pattern of transmittance for each cell is characterized by a finite number of different discrete transmittance level patterns. In a preferred embodiment, these patterns include portions arranged along the respective sides of a parallelogram. In one preferred embodiment, the discrete transmittance level patterns comprise an array of concentric parallelograms. Each parallelogram has a plurality of dot portions arranged along the sides of the parallelogram. The sides of the parallelogram patterns are preferably disposed at a substantial angle to the horizontal to reduce moire and rosette pattern effects and to simplify the reproduction process.

Title
Halftone screen and method of using same
Application Number
894902
Publication Number
4278755
Application Date
August 27, 1979
Publication Date
July 14, 1981
Inventor
Hua Kuang Liu
Tuscaloosa
AL, US
Agent
Harvey G Lowhurst
Harry E Aine
Assignee
Lumin
AL, US
IPC
G03F 5/00
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