Color copying machine provided with color correcting circuit

Claim 2

A color copying machine having a color correcting circuit, said color correcting circuit comprising: means (21,56) for generating reference pattern data on each color; means (3) for printing the reference pattern data generated by said generating means (21,56); means for reading a printed result of the reference pattern data printed by said printing means (3); means (54) for measuring a color reproduction error based on the reference pattern data generated by said reference pattern data generating means (21,56) and the printed result of the reference pattern data read by said reading means; means (23,53) for converting the color reproduction error measured by said color reproduction error measuring means into a Lab color difference; and means (25,52) for calculating a color correction coefficient on each color based on an output of said converting means.

Claim 3

A color copying machine having at least an image reading unit and a printing unit, comprising: means (21,56) for generating reference pattern data on each color; means (162) for converting the reference pattern data generated by said generating means (21,56) and the data obtained by reading a printed matter using said image reading unit, the printed matter being obtained by printing the reference pattern data using said printing unit, into color values based on perception characteristics; multiple regression analyzing means (103) for calculating a color correction coefficient on each color on the basis of the data converted by said converting means (162); rewritable memory means (104) for storing each color correction coefficient calculated by said multiple regression analyzing means (103); and means (105) for performing a color correction operation with respect to said color correction coefficients stored in said memory means (104).

Claim 4

A color copying machine having at least an image reading unit and a printing unit, comprising: means (21,56) for generating reference pattern data on each color; multiple regression analyzing means (103) for calculating a color correction coefficient on each color on the basis of the reference pattern data generated by said generating means (21,56) and the data obtained by reading a printed matter of said printing unit using said image reading unit, said printed matter being obtained by said printing unit; rewritable memory means (104) for storing the color correction coefficients calculated by said multiple regression analyzing means (103); and means (105) for performing a color correction operation with respect to the color correction coefficients stored in said memory means (104).

Claim 5

A color copying machine having at least an image reading unit and a printing unit, comprising: a signal input/output unit (108a) for transferring data between an external device and said color copying machine; a rewritable memory (104) for storing color correction coefficients received from said external device through said signal input/output unit (108a); and a color correction unit (105) for performing a color correction operation with respect to the color correction coefficients stored in said memory, wherein said printing unit is adapted to print the data received from said external device through said signal input/output unit (108a), said reading unit is adapted to send the read image data to said external device through said signal input/output unit (108a).