Method and apparatus for correcting printhead and printer using this printhead

Claim 1

An apparatus for correcting a printing characteristic of a printhead having memory means for storing data, said printhead being manufactured by arraying means for arraying and connecting N-number of circuit boards, each of which has M-number of printing elements in a predetermined direction, in said predetermined direction, machining means for machining a top board covering the M × N - number of printing elements connected by said arraying means, and bonding means for bonding the machined top board and the connected M × N - number of printing elements, said apparatus comprising: measuring means for measuring electrical characteristics of the M × N - number of printing elements, of a unit of the printhead, bonded by said bonding means; inspecting means for driving the unit of the printhead to experimentally print a test pattern on a recording medium, reading the printed test pattern and inspecting unevenness in printing performed by each of the M × N - number of printing elements; monitor means for monitoring an offset in the connections made by said arraying means, a variation in the machining of the top board by said machining means, an offset in the bonding performed by said bonding means, a deviation in the electrical characteristics of the M × N - number of printing elements measured by said measuring means, and unevenness in printing performed by the M × N - number of printing elements inspected by said inspecting means; correction-data generating means for quantifying the factors monitored by said monitor means, summing the quantified factors upon weighting them while taking into account the magnitude of their influence upon printing quality of the printhead, and, on the basis of the sum obtained, generating correction data for correcting printing unevenness of each of the M × N - number of printing elements; and writing means for writing the correction data in said memory means of the printhead.

Claim 19

An apparatus for correcting a printing characteristic of a printhead having a memory for storing data, the printhead being manufactured by arraying and connecting N-number of circuit boards, each of which has M-number of printing elements in a predetermined direction, in the predetermined direction, machining a top board covering the connected M × N - number of printing elements, and bonding the machined top board and the connected M × N - number of printing elements, said apparatus comprising: monitor means for monitoring at least one of an offset in the circuit boards, a variation in the machining of the top board, an offset in the bonding of the printing elements and the top board, a deviation in the electrical characteristics of the M × N - number of printing elements, and unevenness in printing performed by the M × N - number of printing elements; correction-data generating means for quantifying at least one of the factors monitored by said monitor means, summing the at least one quantified factor upon weighting it while taking into account the magnitude of its influence upon printing quality of the printhead, and, on the basis of the sum obtained, generating correction data for correcting printing unevenness of each of the M × N - number of printing elements; and writing means for writing the correction data in the memory of the printhead.

Claim 20

A method of correcting a printing characteristic of a manufactured printhead having N-number of circuit boards, each of which has M-number of printing elements in a predetermined direction, arrayed in the predetermined direction, and a memory for storing information, said method comprising: an arraying step of arraying and connecting the N-number of circuit boards; a machining step of machining a top board covering M × N - number of printing elements connected in said arraying step; a bonding step of bonding the machined top board and the connected M × N - number of printing elements; a measuring step of measuring electrical characteristics of the M × N - number of printing elements, of a unit of the printhead, bonded in said bonding step; an inspecting step of driving the unit of the printhead to experimentally print a test pattern on a recording medium, reading the printed test pattern and inspecting a variation in printing performed by each of the M × N - number of printing elements; a monitoring step of monitoring an offset in the connections made in said arraying step, a variation in the machining of the top board in said machining step, an offset in the bonding performed in said bonding step, a deviation in the electrical characteristics of the M × N - number of printing elements measured in said measuring step, and unevenness in printing performed by the M × N - number of printing elements inspected in said inspecting step; a correction-data generating step of quantifying the factors monitored in said monitor step, summing the quantified factors upon weighting them while taking into account the magnitude of their influence upon printing quality of the printhead, and, on the basis of the sum obtained, generating correction data for correcting printing unevenness of each of the M × N - number of printing elements; and a writing step of writing the correction data in the memory of the printhead.

Claim 22

A method of correcting a printing characteristic of a printhead having memory means capable of storing data, the printhead being manufactured by arraying and connecting N-number of circuit boards, each of which has M-number of printing elements in a predetermined direction, in the predetermined direction, machining a top board covering the connected M × N - number of printing elements, and bonding the machined top board and the connected M × N - number of printing elements, the method comprising: a monitoring step of monitoring at least one of an offset in the circuit boards, a variation in the machining of the top board, an offset in the bonding of the printing elements and the top board, a deviation in the electrical characteristics of the M × N - number of printing elements, and unevenness in printing performed by the M × N - number of printing elements; a correction-data generating step of quantifying at least one of the factors monitored in said monitor step, summing the at least one quantified factor upon weighting it while taking into account the magnitude of its influence upon printing quality of the printhead, and, on the basis of the sum obtained, generating correction data for correcting printing unevenness of each of the M × N - number of printing elements; and a writing step of writing the correction data in the memory means of the printhead.

Claim 23

An apparatus or process for correcting or calibrating a printing characteristic of a printhead formed by an assembly of printhead components, wherein correction or calibration data for the printhead are generated to compensate for, for example, any manufacturing or assembly misalignments or other variations and/or for any variations in electrical and/or mechanical characteristics of printing elements of the printhead.