| 摘要 |
PURPOSE:To make the operation quick by using a sheet of test paper on which regular characters and/or patterns are printed, and extracting the measuring field of view from the entire surface of the paper at an equal interval. CONSTITUTION:A sheet of test paper 41 on which regularly arranged characters and/or patterns are printed is used. The measuring field of view of a photographing camera 2 is relatively moved on the paper 42 at an equal interval. The intensity of the reflected light from the paper 41 wherein light is received at each picture element in the measuring field of view is made to be two variable-density gradations, and binary coded densities are obtained. Then the histogram of the binary coded densities for the picture elements included in the total width of the field of view which is aligned in one direction of the measuring field of view or the picture elements included in the partial length of the width is formed. The quality of printing is evaluated by using the histogram and the moving distance at the equal interval. The average value, the maximum value, the minimum value and the standard deviation of the evaluated results are computed based on each measured field of view and/or a set of specific measured fields of views. |
