Method and apparatus for measuring pattern area percentage for engraving films

Claim 1

Apparatus for measuring pattern area percentages of each of a plurality of columns into which a plurality of engraving films having a matter to be printed on a printing plate are divided, said columns corresponding to the spacing of ink supply adjusting keys of a printing machine comprising: a base; a stage slidably mounted on said base for movement in a direction Y; a transparent member mounted on said stage for receiving one of said plurality of films thereon; optical means mounted on said base for movement in a direction X perpendicular to said direction Y including a light source mounted on one side of said transparent member, a single light detector mounted on the other side of said transparent member facing said light source to produce an output, means between said source and detector defining a rectangular measuring area through which light passes from said source to said detector, and means for adjusting the width of said rectangular area; means for driving said stage and said optical means respectively in said Y and X directions; and control means including means for storing data relating to the number and spacing of the ink supply adjusting keys of the printing machine, the size of the engraving film and the printing position of the film on the printing plate and microprocessor means for determining the divisions of the columns to be measured on said film in accordance with the stored data, producing control signals for adjusting the width of said rectangular area in accordance with the determined divisions, producing drive signals for said drive means and calculating the pattern area percentages of each column from the output of said light detector.

Claim 5

A method for measuring pattern area percentage of each of the columns which are so divided in a matter to be printed, by means of a printing plate as to correspond to the spacings of ink suppy adjusting keys of a printing machine, from an engraving film mounted on an apparatus of the type which provides a transparent member for receiving said film thereon, optical means for measuring light transmission quantities passing through the film from a light source, and moving means for relatively moving both said optical means and said film receiving means, and control means which has a memory in which data concerning light transmission quantities from said optical means are stored and which has means for calculating the pattern area percentage corresponding to each column defined on said printing plate, said method comprising the steps of; placing the engraving film on said transparent member; applying to said control means that data concerning the member and spacings of ink supply adjusting keys mounted on the printing machine, the size of said engraving film and the data concerning printing positions of said film on the printing plate, thereby corresponding the areas of said film on said transparent member to the columns defined on the printing plate; measuring light transmission quantities for each each corresponding area of the film by operating said optical means and moving means; and calculating pattern area percentage of each column by averaging light transmission quantities of each identical areas of engraving films.

Claim 6

A method for measuring pattern area percentage of each of the columns which are so divided in a matter to be printed, by means of a printing plate as to correspond to the spacings of ink suppy adjusting keys of a printing machine, from an engraving film mounted on an apparatus of the type which provides a transparent member for receiving said film thereon, optical means for measuring light transmission quantities passing through the film from a light source, and moving means for relatively moving both said optical means and said film receiving means, and control means which has a memory in which data concerning light transmission quantities from said optical means are stored and which has means for calculating the pattern area percentage corresponding to each column defined on said printing plate, said method comprising the steps of; placing the engraving film on said transparent member; applying to said control means that data concerning the member and spacings of ink supply adjusting keys mounted on the printing machine, the size of said engraving film and the data concerning printing positions of said film on the printing plate, thereby corresponding the areas of said film on said transparent member to the columns defined on the printing plate; measuring light transmission quantities for each each corresponding area of the film by operating said optical means and moving means; and calculating pattern area percentage of each column by averaging light transmission quantities of each identical areas of engraving films.