A heating control section for controlling a voltage applying section and a moving section for reciprocate a carriage on which the first electrode unit is mounted executes heating control for heating a medium while moving the first electrode unit in a scanning direction in at least one of an outgoing path in which the first electrode unit moves in one direction of the scanning direction and a return path in which the first electrode unit moves in the opposite direction. In the heating control, when the first electrode unit is positioned at a first point overlapping with one end section of the medium, the heating control section sets the electric field strength of the first electrode unit to a first electric field strength, when that is positioned at a second point overlapping with center portion of the medium, the second electric field strength is set to be stronger than the first electric field strength, and the movement speed of the first electrode unit at the first point is slower than the movement speed at the second point.

An image forming apparatus comprises a printhead configured to add energy to an image material including a plurality of color development layers that have different color development characteristics and develop colors in response to heat; and a control unit configured to output, based on image data, signal patterns corresponding to the plurality of color development layers and at least one signal pattern corresponding to a color reproduced by causing at least two of the plurality of color development layers to develop colors used to control the energy to be added to the image material by the printhead.

In accordance with an embodiment, an image forming apparatus comprises a thermal head including a plurality of heat generation elements and configured to form an image on a sheet using heat generated by the heat generation element; a health check section configured to diagnose conditions of the heat generation elements; and a control section configured to control the health check section to execute a health check processing when the thermal head is not executing a job of forming an image and diagnose conditions of remaining heat generation elements in a next health check processing when the health check processing is interrupted.

In a printing device, a thermal head has heating elements and prints an image made up of line images. A memory stores sets of parameters, each set including one of first parameters and corresponding one of second parameters. The controller calculates an average consumed power with respect to a line image subject to calculation by dividing a total amount of consumed power by a period of time set in each first parameter, thereby providing average consumed powers for the sets of parameters. The total amount of consumed power is an accumulated consumed power consumed in the heating elements energized during printing in the period of time including a print timing of the line image subject to calculation. The controller sets a cycle time for printing the line image subject to calculation so that each average consumed power does not exceed an upper limit specified by corresponding one of second parameters.

A recording device includes a head including a plurality of nozzles discharging ink droplets and a head including a plurality of nozzles discharging ink droplets of a color identical to that of the ink droplets, a driving circuit configured to drive the former head at a drive voltage and drive the latter head by another drive voltage, an input unit configured to receive an input of selection information selected, based on comparison between a print image printed by the former head and a plurality of other print images G2 printed by the latter head, with the other drive voltage being changed individually, and a control unit configured to control the drive voltage and the other drive voltage, based on the selection information input from the input unit.

A printing apparatus includes a thermal head and a processor. The thermal head includes heat-generating elements and prints on a plurality of lines in a medium. The processor sets a second period within one of the setting periods. The second period is a time period for adjusting a temperature change of the heat-generating elements without printing on the medium, after a first period for printing. The processor determines a n.sup.th line (n: an integer of 2 or greater) among the lines based on printing data. The n.sup.th line is estimated to have a possibility of sticking in printing. The processor adjusts a temperature change of at least a part of the heat-generating elements in the second periods corresponding to at least the n.sup.th line and a (n1).sup.th line. The (n1).sup.th line is printed immediately before the n.sup.th line based on the printing data, to suppress the sticking.

Provided is a printing apparatus which includes a thermal head having a plurality of heat generation elements whose temperatures are controlled by applying a voltage and performing printing on a printing medium and a head drive circuit being supplied periodically with a control signal and print data to control application of a voltage to each of the plurality of heat generation elements. One period of the control signal includes first and second voltage application control periods which are separated from each other. The first voltage application control period is a period in which the printing is performed by controlling the application of a voltage, and the second voltage application control period is a period in which the printing is not performed and a temperature of the thermal head is adjusted by controlling the application of a voltage.

A method for managing printing of data by a thermal printer. The thermal printer includes a thermal print head. The thermal print head has a plurality of points, each point having an effective resistance r.sub.d, and is powered by a power source. The method includes the following actions: measuring a voltage U given by the power source of the thermal printer; measuring an internal resistance r.sub.u of the power source; and computing a duration t for heating a number n of points as a function of the voltage U of the power source, the internal resistance r.sub.u of the power source, at least one effective resistance r.sub.d of at least one point corresponding to a dot to be printed for the printing of the data and as a function of at least one value of parasitic resistance r.sub.p of at least one element of the thermal printer.

A printing apparatus includes a printing head that prints printing data on a printing medium by electric power supplied from a battery, and a processor. The processor is operable to estimate, on the basis of first printing data indicating information on a first printing content to be printed on the printing medium and a remaining battery level of the battery, a first printing executable range which is a range in the first printing content that can be printed on the printing medium, and transmit information indicating the first printing executable range to an external terminal.

Thermal printheads need a power and/or a data cable to deliver energy to the thermal printhead to print. With a wireless thermal printhead, however, a printer can run without using a power or a data cable. By removing the cable, benefits include shrinking the printer size, increasing durability of the printer and making it easier to change a thermal printhead.