A level change point detection section detects a level change point, at which an output level switches, in a first position detection signal Ens1 generated by an encoder or a second position detection signal obtained by increasing the resolution of the Ens1. Each time a predetermined number of level change points is detected, an energization timing determination section determines the timing, at which the predetermined number of level change points have been detected, to be an energization timing for the thermal head.

An image recording apparatus includes a plurality of laser emission parts disposed side by side in a predetermined direction for emitting laser light; an optical system configured to collect a plurality of beams of laser light emitted by the laser emission parts onto the recording target moving relative to the laser emission parts in a direction crossing the predetermined direction; and an output control unit configured to perform control such that energy of laser light emitted from an outermost end laser emission part of the laser emission parts is greater than energy of laser light emitted from a center laser emission part, the outermost end laser emission part emitting laser light to be transmitted through vicinity of an end portion of the optical system, the center laser emission part emitting laser light to be transmitted through a portion other than vicinity of the end portion of the optical system.

A method for printing includes analyzing print quality requirements for a printing area; adjusting settings for heater elements (e.g., energy and/or firing durations) of strobe lines based on the requirements analysis; and providing a plurality of individual strobe signals to the strobe lines. The strobe signals can be transmitted simultaneously, for example with a field-programmable gate array. Analyzing print quality requirements can include separating the printing area into one or more areas of interest, such as rows and/or columns. For each area of interest individual print quality settings (e.g., darkness, contrast, and/or media sensitivity) may be selected.

A head drive device includes a thermal head, a capacitor, a control circuit and a drive circuit. The thermal head has a first group of heat generators and a second group of heat generators having a smaller number of heat generators than the first group. The control circuit selects, based on printing data, whether to perform printing with use of the first group or to perform printing with use of the second group. The drive circuit supplies power of a power source and the power stored in the capacitor to the thermal head when the first group is used, and supplies the power of the power source to the thermal head when the second group is used. The control circuit performs printing with use the first or second group based on the storage state of the capacitor.

A printer includes a processor and a thermal head having a plurality of heating elements to print an image having a plurality of print lines on a printing medium on the basis of printing data, wherein in an initial control period, for any printing data, the processor causes the thermal head to perform a division printing for each of the print lines that are to be printed in the control period, the division printing being such that for each print line to be printed, the plurality of heating elements are divided into a plurality of subgroups and the respective subgroups of the heating elements are activated in a time-divided manner, and wherein in a normal period after the control period, the processor causes the thermal head performs a non-division printing for at least some of the print lines that are to be printed in the normal period.

A quick release print head includes a heating block, a nozzle tube and a connecting tube. The nozzle tube is inserted in the heating block. One end of the nozzle tube has a nozzle and the other end is extended with an extension tube exposed to the heating block. The connecting tube is connected with the extension tube. Whereby, the extension tube extended from the nozzle tune is exposed to the heating block so that the nozzle tube disposed near the heating block cannot be disassembled. Thus, a process of replacing components by heating a nozzle can be bypassed, and advantages of quick disassembly and easy maintenance of the print head can be achieved.

A printing device comprises: a print head configured to print a plurality of print lines on a medium to be printed, the medium being conveyed in a conveying direction; and a processor configured to control the print head. The processor is configured to: control the print head to print each of the plurality of print lines by a number of printing times which is once or a plurality of times by time division according to print data for printing each of the plurality of print lines; and in printing of a first print line and a second print line to be printed after the first print line of the plurality of print lines by the print head, the second print line being adjacent to the first print line along the conveying direction, control the print head to perform, after printing the first print line before printing the second print line, complementary printing that complements missing print estimated to occur between the first print line and the second print line in a case where a number of the printing times in the first print line and a number of the printing times in the second print line are set to different values from each other, and a number of the printing times is set to two or more.

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.

An asymmetric thermal print head includes a print head body and a plurality of print elements supported on the print head body. The print elements are aligned along a first axis. Each print element includes a heater portion having a burn width measured along the first axis corresponding to a first print resolution, and a burn length measured along a second axis, which is perpendicular to the first axis, corresponding to a second print resolution. The second print resolution is higher than the first print resolution. One or more control circuits are configured to individually activate the print elements.

A printing device includes: a thermal head including heater elements arrayed into a line along an array direction intersecting a conveying direction of a printing medium; and controller that causes the thermal head to print onto the printing medium based on multiple line print data, each of the multiple line print data being data into which print data is divided along the array direction. The controller performs either of a first energization control to energize the heater elements in one line cycle for printing based on a single line print data among the multiple line print data and a second energization control to energize the heater elements so that a non-energization period in which the heater elements are not energized is included in the one line cycle, depending on a temperature of the thermal head.