| 摘要 |
PROBLEM TO BE SOLVED: To eliminate visible dot and luminance unevenness, and to suppress the occurrence of a moire, by making the arrangement of dots satisfy a specified condition and using randomly arranged and formed members. SOLUTION: A dot forming surface is divided into an area of a square of 1-4mm<2> , and the dots are arranged to be formed so that a function G (R) obtained from arrangement of all dots existing in the area is 0<S1/S2<0.4 in the range of 3<=R/R0<=6. Where, R is distance from the central position of the dot to the central position of the other dot, R0 is a value L/√N dividing the length of one side of a square area by the square root of the number of dots N. The G (R) is the function obtained by calculating a weighted means of a dynamic size distributive function g (R) and approximating using a method of least squares, and S1 is the value obtained integrating|G (R)-(mean value of G (R)|by the R/R0, and S2 is the value obtained by integrating the mean value of G (R) by the R/R0.
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