Printing apparatus, control method therefor, and computer-readable memory

Claim 2

A printing apparatus for forming an image of print dots by discharging ink to a printing medium on the basis of input image information, comprising: a first printhead having a first array of a plurality of ink orifices arranged substantially in a printing medium conveying direction for discharging a first ink, and a second array of a plurality of ink orifices arranged substantially in the printing media conveying direction, for discharging a second ink of a type different from that of the first ink, wherein the first array and the second array are arranged in a main scanning direction different from the printing media conveying direction; a second printhead having a third array and a fourth array which are laid out symmetrically in the main scanning direction to each of the first array and the second array of said first printhead; a distribution unit that distributes print dot data corresponding to print dots to be printed based on the input image information to first and second print dot data; and a printing controller that controls performance of printing first print dots by said first printhead in accordance with the first print dot data and performance of printing second print dots by said second printhead in accordance with the second print dot data, wherein when said first and second printheads are used for printing the first and second print dots, both said first printhead and said second printhead perform bi-directional printing by scanning said first and second printheads bi-directionally in the main scanning direction.

Claim 3

The apparatus according to claim 1 , further comprising a first printing mode of performing reciprocal printing while said first and second printheads are relatively reciprocally scanned on a printing medium.

Claim 4

The apparatus according to claim 2 , wherein said distribution unit generates the first and second print dot data for each path in multipath printing control by thinning out print dots using a mask pattern.

Claim 5

The apparatus according to claim 3 , wherein the mask pattern is a random mask pattern in which print dots and non-print dots are laid out at random.

Claim 6

The apparatus according to claim 3 , wherein the mask pattern comprises two complementary mask patterns.

Claim 7

The apparatus according to claim 5 , wherein a predetermined position of the mask pattern is set to “mask OFF”.

Claim 8

The apparatus according to claim 3 , wherein the mask pattern comprises two uncomplementary mask patterns.

Claim 9

The apparatus according to claim 2 , wherein said distribution unit generates the first and second print dot data for each path in multipath printing control by thinning out print dots using a thinning pattern based on coordinates of the print dots.

Claim 10

The apparatus according to claim 2 , wherein said distribution unit generates the first and second print dot data for each path in multipath printing control by thinning out print dots.

Claim 11

The apparatus according to claim 2 , further comprising a second printing mode of forming an image while either one of said first and second printheads is scanned on a forward path or return path, and said apparatus operates by selectively using the first and second printing modes.

Claim 12

The apparatus according to claim 10 , wherein said first and second printheads are reciprocally scanned at a higher speed in the first printing mode than the second printing mode.

Claim 13

The apparatus according to claim 10 , further comprising: first color correction means for performing color correction processing corresponding to the first printing mode; and second color correction means for performing color correction processing corresponding to the second printing mode.

Claim 14

The apparatus according to claim 10 , further comprising: detection means for detecting presence/absence of a fault in said first and second printheads; and selection means for selectively using the first and second printing modes on the basis of a detection result of said detection means, and when said detection means detects a fault in either one of said first and second printheads, said apparatus is switched to the second printing mode using the other printhead.

Claim 15

The apparatus according to claim 1 , wherein said first and second printheads are inkjet printheads for performing printing by discharging ink.

Claim 16

The apparatus according to claim 1 , wherein said first and second printheads discharge ink using heat energy and comprise heat energy converters for generating heat energy to be supplied to ink.

Claim 17

A control method for a printing apparatus for forming an image of print dots by discharging ink to a printing medium on the basis of input image information, the apparatus including a first printhead having a first array of a plurality of ink orifices arranged substantially in a printing medium conveying direction for discharging a first ink, and a second array of a plurality of ink orifices arranged substantially in the printing medium conveying direction, for discharging a second ink of a type different from that of the first ink, wherein the first array and the second array are arranged in a main scanning direction different from the printing medium conveying direction, and a second printhead having a third array and a fourth array which are laid out symmetrically in the main scanning direction to each of the first array and the second array of the first printhead, said method comprising: a distribution step, of distributing print dot data corresponding to print dots to be printed based on the input image information to first and second print dot data; and a printing control step, of controlling performance of printing first print dots by said first printhead in accordance with the first print dot data and performance of printing second print dots by said second printhead in accordance with the second print dot data, wherein when said first and second printheads are used for printing the first and second print dots, both said first printhead and said second printhead perform bi-directional printing by scanning said first and second printheads bi-directionally in the main scanning direction.

Claim 18

A control method for a printing apparatus for forming an image of print dots by discharging ink to a printing medium on the basis of input image information, the apparatus including a first printhead having a first array of a plurality of ink orifices arranged substantially in a printing medium conveying direction for discharging a first ink, and a second array of a plurality of ink orifices arranged substantially in the printing medium conveying direction, for discharging a second ink of a type different from that of the first ink, wherein the first array and the second array are arranged in a main scanning direction different from the printing medium conveying direction, and a second printhead having a third array and a fourth array which are laid out symmetrically in the main scanning direction to each of the first array and the second array of the first printhead, said method comprising: a distribution step, of distributing print dot data corresponding to print dots to be printed based on the input image information to first and second print dot data; and a printing control step, of controlling performance of printing first print dots by said first printhead in accordance with the first print dot data and performance of printing second print dots by said second printhead in accordance with the second print dot data, wherein when said first and second printheads are used for printing the first and second print dots, both said first printhead and said second printhead perform bi-directional printing by scanning said first and second printheads bi-directionally in the main scanning direction.

Claim 19

The method according to claim 16 , wherein said apparatus comprises a first printing mode of performing reciprocal printing while said first and second printheads are relatively reciprocally scanned on a printing medium.

Claim 20

The method according to claim 17 , wherein the distribution step comprises generating the first and second print dot data for each path in multipath printing control by thinning out print dots using a mask pattern.

Claim 21

The method according to claim 18 , wherein the mask pattern is a random mask pattern in which print dots and non-print dots are laid out at random.

Claim 22

The method according to claim 18 , wherein the mask pattern comprises two complementary mask patterns.

Claim 23

The method according to claim 20 , wherein a predetermined position of the mask pattern is set to “mask OFF”.

Claim 24

The method according to claim 18 , wherein the mask pattern comprises two uncomplementary mask patterns.

Claim 25

The method according to claim 17 , wherein the distribution step comprises generating the first and second print dot data for each path in multipath printing control by thinning out print dots using a thinning pattern based on coordinates of the print dots.

Claim 26

The method according to claim 17 , wherein the distribution step comprises generating the first and second print dot data for each path in multipath printing control by thinning out print dots.

Claim 27

The method according to claim 17 , wherein said apparatus has a second printing mode of forming an image while either one of said first and second printheads is scanned on a forward path or return path, and said method selectively uses the first and second printing modes.

Claim 28

The method according to claim 25 , wherein said first and second printheads are reciprocally scanned at a higher speed in the first printing mode than the second printing mode.

Claim 29

The method according to claim 25 , further comprising: a first color correction step of performing color correction processing corresponding to the first printing mode; and a second color correction step of performing color correction processing corresponding to the second printing mode.

Claim 30

The method according to claim 25 , further comprising: a detection step of detecting presence/absence of a fault in said first and second printheads; and a selection step of selectively using the first and second printing modes on the basis of a detection result in the detection step, and when a fault is detected in either one of said first and second printheads in the detection step, said method switches the mode to the second printing mode using the other printhead.

Claim 31

The method according to claim 16 , wherein said first and second printheads are inkjet printheads for performing printing by discharging ink.

Claim 32

The method according to claim 16 , wherein said first and second printheads discharge ink using heat energy and comprise heat energy converters for generating heat energy to be supplied to ink.

Claim 33

A computer-readable memory storing control program codes for a printing apparatus for forming an image of print dots by discharging ink to a printing medium on the basis of input image information, the apparatus including a first printhead having a first array of a plurality of ink orifices arranged substantially in a printing medium conveying direction for discharging a first ink, and a second array of a plurality of ink orifices arranged substantially in the printing medium conveying direction, for discharging a second ink of a type different from that of the first ink, wherein the first array and the second array are arranged in a main scanning direction different from the printing medium conveying direction, and a second printhead having a third array and a fourth array which are laid out symmetrically in the main scanning direction to each of the first array and the second array of the first printhead, said memory storage program comprising: program code for a distribution step of distributing print dot data corresponding to print dots to be printed based on the input image information to first and second print dot data; and program code for a printing control step of controlling performance of printing first print dots by said first printhead in accordance with the first print dot data and performance of printing second print dots by said second printhead in accordance with the second print dot data, wherein when said first and second printheads are used for printing the first and second print dots, both said first printhead and said second printhead perform bi-directional printing by said first and second printheads bi-directionally in the main scanning direction.

Claim 34

A computer-readable memory storing control program codes for a printing apparatus for forming an image of print dots by discharging ink to a printing medium on the basis of input image information, the apparatus including a first printhead having a first array of a plurality of ink orifices arranged substantially in a printing medium conveying direction for discharging a first ink, and a second array of a plurality of ink orifices arranged substantially in the printing medium conveying direction, for discharging a second ink of a type different from that of the first ink, wherein the first array and the second array are arranged in a main scanning direction different from the printing medium conveying direction, and a second printhead having a third array and a fourth array which are laid out symmetrically in the main scanning direction to each of the first array and the second array of the first printhead, said memory storage program comprising: program code for a distribution step of distributing print dot data corresponding to print dots to be printed based on the input image information to first and second print dot data; and program code for a printing control step of controlling performance of printing first print dots by said first printhead in accordance with the first print dot data and performance of printing second print dots by said second printhead in accordance with the second print dot data, wherein when said first and second printheads are used for printing the first and second print dots, both said first printhead and said second printhead perform bi-directional printing by said first and second printheads bi-directionally in the main scanning direction.