Method of generating optimal pattern of light emission and method of measuring contour noise and method of selecting gray scale for plasma display panel

A method of measuring a contour noise of a plasma display panel, comprising steps of:

• determining a plurality of sub-field arrays;
• calculating a contour noise degree between a contour noise free gray level being set in advance and each gray level of the sub-field arrays;
• summing up the contour noise degree of each gray level calculated;
• and
• selecting any one among the sub-field arrays in accordance with the sum of the contour noise degree.

A method of measuring a contour noise of a plasma display panel, comprising steps of:

• determining a plurality of sub-field arrays to which brightness weighting values are given by sub-fields;
• calculating a contour noise degree between a contour noise free gray level being set in advance and each gray level of the sub-field arrays;
• dividing the contour noise degree by a threshold value set differently in a gray level scope that is not larger than a specific gray level value and a gray level scope that is not less than the specific gray level value;
• summing up the contour noise degree divided by the threshold value;
• and
• selecting a sub-field array, the sum of whose contour noise degree is minimal.

A method of selecting a gray level for a plasma display panel, comprising steps of:

• determining a sub-field array to which brightness weighting values are given by sub-fields;
• calculating a contour noise degree between a contour noise free gray level being set in advance and each gray level of the sub-field array;
• comparing the contour noise degree with the threshold value being set in advance, then selecting only gray levels whose contour noise degree is smaller than the threshold value;
• and
• displaying an image only with the selected gray level.

A method of selecting a gray level for a plasma display panel, comprising steps of:

• determining a plurality of sub-field arrays to which brightness weighting values are given;
• calculating a contour noise degree between a contour noise free gray level being set in advance and each gray level of the sub-field arrays;
• comparing the contour noise degree with the threshold value being set in advance, then selecting only gray levels whose contour noise degree is smaller than the threshold value;
• and
• selecting a sub-field array with its frequency of use maximal in reference of the frequency of use of the selected gray level.

A method of selecting a gray level for a plasma display panel, comprising steps of:

• determining a plurality of sub-field arrays to which brightness weighting values are given;
• calculating a contour noise degree between a contour noise free gray level being set in advance and each gray level of the sub-field arrays;
• comparing the contour noise degree with the threshold value being set in advance, then selecting only gray levels whose contour noise degree is smaller than the threshold value and setting a gray level that is bigger than the threshold value as a non-selected gray level;
• and
• calculating the frequency of use of the non-selected gray level, and selecting a sub-field array with its frequency of use minimal.