In image forming apparatus, a control unit determines nozzles corresponding to the image to be printed, correspondingly to a position of a print sheet, and causes a recording head to eject ink from the nozzles. A correction processing unit performs a correction process corresponding to each of plural ink ejection malfunction positions in the image. If the number of the ink ejection malfunction positions detected with a predetermined ink droplet size exceeds a predetermined upperlimit value, the correction processing unit prints a test pattern using the control unit with an ink droplet size larger than the predetermined ink droplet size, determines as a preferential ink ejection malfunction position an ink ejection malfunction position that ink ejection malfunction is also detected in the test pattern on the basis of a scanned image of the test pattern, and preferentially performs the correction process for the preferential ink ejection malfunction position.

In an image forming apparatus, a recording head ejects ink corresponding to an image to be printed, using arranged nozzles. A control unit determines nozzles corresponding to the image to be printed, correspondingly to a position of a print sheet, and causes the recording head to eject ink from the nozzles. A correction processing performs a correction process corresponding to each of ink ejection malfunction positions in the image. Further, the correction processing unit (a) sets the ink ejection malfunction positions as targets of the correction process in advance, and (b) excludes from the targets on the basis of a sheet size of the print sheet an ink ejection malfunction position corresponding to a nozzle that is not used for the print sheet among nozzles corresponding to the plural ink ejection malfunction positions and thereafter performs the correction process for the targets.

A head alignment apparatus for determining a reference position using position synchronization and aligning a plurality of head modules according to the reference position, and a substrate treating system including the same are provided. The head alignment apparatus may include, a reference position determining unit for determining a first reference position of a head transfer, in which a plurality of inkjet head modules are installed; and a mounting position determining unit for determining a second reference position of the inkjet head module based on the first reference position so that the inkjet head module can be moved from a current position to a second reference position, wherein the reference position determining unit determines a first reference position using a first image sensor installed on the same plane as the inkjet head module and a second image sensor installed facing the inkjet head module.

The inventive concept provides an inkjet printing method. The inkjet printing method for discharging an ink on a substrate using a head having a plurality of nozzles formed thereon includes determining a grade of nozzles by measuring a discharge performance of the nozzles, which is a grading step; selecting a use nozzle that can participate in printing the substrate among the nozzles based on the grade determined at the grading step, which is a nozzle selecting step; and discharging the ink on the substrate using at least one nozzle among use nozzles, which is a printing step.

A multifunction peripheral includes a conveyance roller, a print engine, a scanner, and a controller. The controller is configured to perform: driving the conveyance roller to convey a recording medium and controlling the print engine to record, on the recording medium, a test image based on test image data with recording agent; after recording the test image, controlling the scanner to generate scan data of the test image recorded on the recording medium; after generating the scan data, extracting, based on the scan data and the test image data, stain data indicative of a stain caused by transfer of the recording agent from the conveyance roller to the recording medium; after extracting the stain data, generating correction data by removing the stain data from the scan data; and executing particular processing by using the correction data.

An image inspection device includes: an inspection condition setting unit for setting, as an inspection condition, a determination criterion when detecting a defective image; an imaging unit that performs capturing a print image and outputs a captured image obtained by the capturing; and a defective image detection unit that detects a defective image from the captured image on the basis of the inspection condition. The inspection condition setting unit is configured to be able to set, as the inspection condition, first parameter values and second parameter values that are two different determination criteria. The defective image detection unit performs first detection processing of detecting a defective image from the captured image on the basis of the first parameter values and second detection processing of detecting a defective image from the captured image on the basis of the second parameter values.

There is provided a liquid discharging apparatus including: a liquid discharging head having a nozzle; an electrode; a voltage supplier; a first output part configured to output a first signal corresponding to an electric change, of the electrode or the liquid discharging head, caused in a case that the liquid discharging head performs inspection driving for discharging a liquid from the nozzle toward the electrode; a second output part connected to the electrode; a high pass filter; a third output part connected to the electrode via the high pass filter; and a controller. The controller is configured to: determine whether the liquid is normally discharged based on the first signal; and determine whether a short circuit is formed between the liquid discharging head and the electrode based on a second signal outputted from the second output part and a third signal outputted from the third output part.

The disclosure concerns a test apparatus comprising a drum (100) configured such that ink drops (200) deposited on the surface of the drum form a printed marking (210) on the surface of the drum. The test apparatus further comprises an ink removal unit (300) configured to remove ink from the surface of the drum. The drum is at least partially transmissive of light and a light source (800) is disposed inside the drum to controllably illuminate the drum.

A determination signal indicates whether each of a plurality of nozzles of a liquid ejection head is an abnormal nozzle. A controller stores, in a memory, information on a nozzle determined to be the abnormal nozzle among the plurality of nozzles; in response to receiving a particular signal and determining that the memory does not store abnormality flag information and that the number of the abnormal nozzle stored in the memory is larger than a first threshold value, control a recovery device to perform a recovery operation; and in response to receiving the particular signal and determining that the memory stores the abnormality flag information and that the number of the abnormal nozzle is larger than a second threshold value, control the recovery device to perform the recovery operation. The second threshold value is smaller than the first threshold value.

A droplet discharging apparatus may include a transfer part moving a substrate including a first target position in a first direction, an inkjet head disposed on the transfer part and discharging a first droplet to the first target position of the substrate, a first camera positioned in a second direction opposite to the first direction of the inkjet head, the first camera acquiring a first image corresponding to the first target position of the substrate, a second camera positioned in the first direction of the inkjet head, the second camera acquiring a second image corresponding to the first target position of the substrate, and an image processor receiving the first image and the second image, and comparing the first image and the second image to inspect a discharge state of the first droplet.