A compensation method includes determining position information of an abnormal nozzle of an inkjet head; acquiring printing parameters, determining first data corresponding to the abnormal nozzle, and based on the position information of the abnormal nozzle and the printing parameters, determining position information of a compensation nozzle for compensating the first data corresponding to the abnormal nozzle; and based on the printing parameters, acquiring second data of the compensation nozzle in a normal printing state which includes ink out data and ink holding data, determining an address of the ink holding data, and generating compensation data by writing the first data into the address of the ink holding data. A compensation device includes: an abnormal nozzle position determination module; a compensation nozzle position determination module; and a compensation data generation module. An inkjet printer includes: a controlling unit, an inkjet head unit, and a nozzle compensation unit.

A liquid discharge apparatus includes: an applicator configured to apply a first liquid onto a surface of a fabric medium to increase repellency of the surface of the fabric medium; a head configured to discharge a second liquid onto the surface of the fabric medium, onto which the first liquid has been discharged; a detector configured to detect the repellency of the surface of the fabric medium on which the first liquid has been discharged; circuitry configured to: determine whether the repellency detected by the detector is equal to or larger than a predetermined repellency; and control the applicator to further apply the first liquid onto the surface of the fabric medium in response to a determination in which the repellency detected by the detector is lower than the predetermined repellency.

A print head having an ejection portion that ejects a liquid includes a determination portion that executes a first determination process of determining whether or not a first error occurs in which replacement of the print head or replacement of a hardware coupled to the print head is required and a second determination process of determining whether or not a second error occurs in which neither the replacement of the print head nor the replacement of the hardware coupled to the print head is required, and a light emitting portion that emits light according to a result of determination in the determination portion.

There is provided a head module in which a first direction is a main scanning direction, including: a first nozzle row including a first nozzle; a second nozzle row including a second nozzle; and a third nozzle row including a third nozzle, in which a distance P1 between the first nozzle row and the second nozzle row in the first direction and a distance P2 between the first nozzle row and the third nozzle row in the first direction are expressed as P1:P2=E1:O1 where a value E1 is a positive even number and a value O1 is a positive odd number satisfying O1>E1.

The disclosed embodiments include a method to compensate for defective printer nozzles. The method can include detecting a defective printer nozzle and initiating a print job including image data of the defective printer nozzle for a pixel location of an image. The image is to be printed in accordance with a print mask that maps printer nozzles to pixel locations of the image. The method can include modifying the image to print the image data in a neighboring pixel location relative to the pixel location of the image and printing the modified image.

A method for inspecting an ink discharge status based on a temperature change of an energy generating element includes calculating a difference value between a value obtained by statistics of information indicating ink discharge statuses obtained for a plurality of nozzles close to a target nozzle and the information obtained for the target nozzle; comparing the calculated difference value with a predetermined threshold; and judging the ink discharge status for the target nozzle based on a result of the comparison. This enables to appropriately detect a nozzle which is in a discharge failure status due to an ink droplet adhered to a discharge surface of a printhead or the like.

A recording apparatus includes a liquid ejection head, where the liquid ejection head includes: an ejection port, a first substrate, and a temperature detection element. The ejection port ejects liquid and includes a protrusion extending toward an ejection port inside. The first substrate includes a heating element that ejects liquid from the ejection port using heat. The temperature detection element detects temperature of the first substrate. Driving of the heating element is controlled based on whether a difference between a voltage value Vp1 measured by the temperature detection element and a preset voltage value Vp01 has a positive value within or outside a predetermined range or a negative value outside the predetermined range. The voltage value Vp1 is measured when a temperature change amount becomes maximum in a temperature falling process of a second substrate located, after the heating element is driven, at a position corresponding to the heating element.

There is provided a liquid ejection apparatus, including: a head; a signal output circuit; a discharge mechanism; a controller; and a memory in which association information is stored. The controller is configured to: diagnose a degree of defectiveness of the head based on a signal from the signal output circuit; and receive, from a user, an input of discharge amount information. In response to the input of the discharge amount information, the controller is configured to: control the discharge mechanism to discharge a liquid by a discharge amount corresponding to the discharge amount information; and change the association in the association information based on the discharge amount corresponding to the discharge amount information and a discharge amount that corresponds to the degree of the defectiveness of the head.

A print element substrate comprises print elements generating thermal energy for ejecting liquid; and a temperature detection element circuit including temperature detection elements provided corresponding to each of the print elements, and reading temperature information by selectively energizing one of the temperature detection elements, wherein the temperature detection element circuit includes: a signal processing portion outputting a selection signal having a second voltage amplitude larger than a first voltage amplitude, based on an input signal having the first voltage amplitude; a selection switch provided for each of the plurality of temperature detection elements, selecting the temperature detection element; and a first read switch provided for each of the plurality of temperature detection elements, reading a voltage of a terminal of one of the temperature detection element selected by the selection switch, and wherein the selection switch and the first read switch are driven by using the selection signal.

A liquid ejection apparatus includes a liquid ejection head and a controller. The controller configured to perform: determining whether a discharge failure occurs in a first nozzle; in a case where it is determined that the discharge failure occurs in the first nozzle, determining whether a certain condition is satisfied; in a case where it is determined that the certain condition is satisfied: applying a flushing signal to a second driving element; applying a driving signal to the second driving element; determining whether the discharge failure occurs in a second nozzle; in a case where it is determined that the discharge failure does not occur in the second nozzle, executing a first purge; and in a case where it is determined that the discharge failure occurs in the second nozzle, executing a second purge.