A driving pulse to be applied to a plurality of print elements in a print element array is decided based on the deviation of the discharge amount from the print elements.

A wide array printhead module includes a plurality of printhead die. Each of the printhead die includes a number of sensors to measure properties of a number of elements associated with the printhead die. The wide array printhead module further includes an application specific integrated circuit (ASIC) to command and control each of the printhead die. The ASIC is located off any of the printhead die.

A controller of an inkjet printer: calculates second density correction values for respective nozzles arranged in a predetermined direction to print a second line of an image data, by using gray-level values of pixels in the second line of the image data corresponding to the respective nozzles and first density correction values for the respective nozzles to print a first line of the image data printed immediately prior to the second line; and corrects the gray-level values of the pixels in the second line of the image data corresponding to the respective nozzles, by using the calculated second density correction values.

A liquid ejection head unit includes a first energy generating element that generates energy that applies pressure to a liquid in the first pressure chamber; a second energy generating element that generates energy that applies pressure to a liquid in the second pressure chamber; a nozzle flow path which communicates the first pressure chamber and the second pressure chamber and in which a nozzle that ejects a liquid is provided; a drive circuit that drives the first energy generating element and the second energy generating element by applying a drive pulse; a detection circuit that detects a parameter related to a physical property of a liquid in the second pressure chamber; wherein a controller drives the first energy generating element by the drive circuit, and performs a first detection operation of detecting the parameter in the second pressure chamber by the detection circuit.

A liquid discharge apparatus includes a liquid discharge head and a head drive controller. The liquid discharge head includes an actuator including an electromechanical transducer element. The head drive controller controls the liquid discharge head. The head drive controller includes a drive waveform generator and a voltage updater. The drive waveform generator generates a drive waveform to be applied to the electromechanical transducer element. The voltage updater updates a voltage value of the drive waveform to a larger value with an elapse of time. The voltage updater sets a time interval of update of the voltage value to be longer as a number of times of the update is greater.

A liquid discharging apparatus has: a head unit that discharges a liquid; and a control unit that controls the operation of the head unit. The head unit has: a driving circuit board that includes a driving signal output circuit that outputs a driving signal, and also includes a substrate on which the driving signal output circuit is mounted; a discharge head that includes a driving element driven by the driving signal, a switching circuit that selectively supplies the driving signal to the driving element, and a nozzle plate in which a nozzle is formed, the nozzle discharging the liquid by being driven by the driving element; a first flow path member through which the liquid to be discharged from the nozzle passes; and a first heat dissipating member coupled to the driving circuit board. The first heat dissipating member is coupled to the first flow path member.

A liquid ejecting apparatus includes: an ejection section ejecting a liquid; a state detection section detecting a state of the ejection section; a determination section determining whether or not the ejection section has an abnormality; a recording section recording a determination result of the determination section; a temperature detection section detecting a temperature of the ejection section; and a maintenance section executing maintenance processing on the ejection section, in which when the recording section records abnormality information indicating the abnormality of the ejection section as the determination result by determining that the abnormality occurred in the ejection section by the determination section, and the temperature detection section detects a temperature that is out of an inspection temperature range in which the state detection section detects the state of the ejection section, the abnormality information recorded in the recording section is reset if the maintenance section executes the maintenance processing.

Methods and apparatus to control a heater associated with a printing nozzle are disclosed. A method comprising controlling a heater associated with a printing nozzle to reduce a heat output of the heater based on a determination that the printing nozzle is outside a print area and printing an image on a substrate using other printing nozzles while the heat output of the heater is reduced.

In accordance with an embodiment, an ink circulation device comprises a pressure chamber including at least two flow holes through which ink flows; a piezoelectric vibration plate constituting a part of a wall of the pressure chamber and to be driven to increase or decrease an inner volume of the pressure chamber; a valve for opening and closing at least one of the two flow holes; a heater affixed on the piezoelectric vibration plate; and a connection section connecting the pressure chamber to an inkjet head.

A memory circuit for a print component including a plurality of I/O pads, including an analog pad, to connect to a plurality of signals paths which communicate operating signals to the print component, and a memory component to store memory values associated with the print component. A control circuit to, in response to identifying a sequence of operating signals representing a memory read, provide a first analog signal on the analog pad in parallel with a second analog signal from the print component to provide an analog electrical value on the analog pad representing stored memory values selected by the memory read.