Regarding an image forming apparatus for printing an input image and including a print head having a head sensor configured to sense information from the input image printed on a print medium, there is a method of determining a head sensor position parameter in the image forming apparatus. The method includes printing a first swath of the input image on the print medium and determining the head sensor position parameter by performing a sub-method. The sub-method includes capturing, via the head sensor, a target image from the printed first swath, comparing the target image to a reference image for the first swath based upon the input image, and determining the head sensor position parameter based on a relative shift between the target image and the reference image.

Regarding an image forming apparatus for printing an input image and including a print head having a head sensor configured to sense information from the input image printed on a print medium, there is a method of determining a head sensor position parameter in the image forming apparatus. The method includes printing a first swath of the input image on the print medium and determining the head sensor position parameter by performing a sub-method. The sub-method includes capturing, via the head sensor, a target image from the printed first swath, comparing the target image to a reference image for the first swath based upon the input image, and determining the head sensor position parameter based on a relative shift between the target image and the reference image.

A flow deflector, an inkjet printing method, an inkjet printing device, and a method for manufacturing a display substrate are provided. The flow deflector includes a plate-shaped body, and the plate-shaped body includes a first surface and a second surface opposite to each other, a plurality of through holes is arranged in the plate-shaped body, each of the plurality of through holes penetrates from the first surface to the second surface, and comprises a first opening formed on the first surface and a second opening formed on the second surface, and an opening area of the first opening is larger than an opening area of the second opening.

A flow deflector, an inkjet printing method, an inkjet printing device, and a method for manufacturing a display substrate are provided. The flow deflector includes a plate-shaped body, and the plate-shaped body includes a first surface and a second surface opposite to each other, a plurality of through holes is arranged in the plate-shaped body, each of the plurality of through holes penetrates from the first surface to the second surface, and comprises a first opening formed on the first surface and a second opening formed on the second surface, and an opening area of the first opening is larger than an opening area of the second opening.

There is disclosed a non-transitory machine-readable medium encoded with instructions executable by a processor and comprising instructions to: control print apparatus to print a test pattern 11 on a test region of a print medium 4; receive test data relating to the test pattern 11 printed on the print medium 4 from a sensor 8; analyse the test data with reference to baseline data to determine if the test pattern 11 satisfies a print quality criterion; output an instruction to operate the print apparatus in a first mode, in which a pre-printing treatment is not applied to the print medium, in response to determining that the test pattern 11 satisfies the print quality criterion, the pre-printing treatment comprising wiping a printing surface of the print medium with a wiper element 10, 20; and output an instruction to operate the print apparatus in a second mode, in which the pre-printing treatment is applied to the print medium 4, in response to determining that the test pattern 11 satisfies the print quality criterion.

There is disclosed a non-transitory machine-readable medium encoded with instructions executable by a processor and comprising instructions to: control print apparatus to print a test pattern 11 on a test region of a print medium 4; receive test data relating to the test pattern 11 printed on the print medium 4 from a sensor 8; analyse the test data with reference to baseline data to determine if the test pattern 11 satisfies a print quality criterion; output an instruction to operate the print apparatus in a first mode, in which a pre-printing treatment is not applied to the print medium, in response to determining that the test pattern 11 satisfies the print quality criterion, the pre-printing treatment comprising wiping a printing surface of the print medium with a wiper element 10, 20; and output an instruction to operate the print apparatus in a second mode, in which the pre-printing treatment is applied to the print medium 4, in response to determining that the test pattern 11 satisfies the print quality criterion.

The invention relates to a method for detecting the presence of a jet from a multi-jet print head of an inkjet printer comprising a plurality of nozzles (4), at least one 1.sup.st and one 2nd deviation electrode (14a, 14b) for each jet, in which: the inkjet is produced by one of the nozzles, at a frequency f.sub.stim1, and is then charged by a voltage V.sub.THT at a frequency f.sub.THT, f.sub.THT not being an integer multiple or sub-multiple of f.sub.stim1; a jet charge signal is detected, derived from sampling, at frequency f.sub.stim1, of the voltage at frequency f.sub.THT, at least one spectral component of this signal being used to detect the presence of the jet.

The invention relates to a method for detecting the presence of a jet from a multi-jet print head of an inkjet printer comprising a plurality of nozzles (4), at least one 1.sup.st and one 2nd deviation electrode (14a, 14b) for each jet, in which: the inkjet is produced by one of the nozzles, at a frequency f.sub.stim1, and is then charged by a voltage V.sub.THT at a frequency f.sub.THT, f.sub.THT not being an integer multiple or sub-multiple of f.sub.stim1; a jet charge signal is detected, derived from sampling, at frequency f.sub.stim1, of the voltage at frequency f.sub.THT, at least one spectral component of this signal being used to detect the presence of the jet.

An inkjet recording apparatus 100 which records on a transferred recording medium X by an inkjet scheme, wherein the inkjet recording apparatus 100 includes guide rolls R for guiding the recording medium X, the recording medium X being negatively charged, recording units 1, 2, 3, and 4 formed of a plurality of recording heads 1a, 2a, 3a, and 4a for spraying ink onto the recording medium X, and a conductive frame unit 11 for supporting the recording heads 1a, 2a, 3a, and 4a, the recording heads 1a, 2a, 3a, and 4a and the conductive frame unit 11 having a continuity relation and the recording heads 1a, 2a, 3a, and 4a being grounded via the conductive frame unit 11.

An inkjet recording apparatus 100 which records on a transferred recording medium X by an inkjet scheme, wherein the inkjet recording apparatus 100 includes guide rolls R for guiding the recording medium X, the recording medium X being negatively charged, recording units 1, 2, 3, and 4 formed of a plurality of recording heads 1a, 2a, 3a, and 4a for spraying ink onto the recording medium X, and a conductive frame unit 11 for supporting the recording heads 1a, 2a, 3a, and 4a, the recording heads 1a, 2a, 3a, and 4a and the conductive frame unit 11 having a continuity relation and the recording heads 1a, 2a, 3a, and 4a being grounded via the conductive frame unit 11.