A thermal printer includes heating elements that generate heat according to amounts of applied energy, an energy applier that applies energy to the heating elements, a memory that stores a gradation table where energy levels to be applied to the heating elements are set for gradation levels based on a relationship between dot area ratios of an image and the amounts of energy applied to the heating elements, and a controller that transfers control data multiple times to the energy applier based on the gradation table to control the amounts of energy to be applied by the energy applier to the heating elements, each of the control data corresponding to different amounts of energy.

Example implementations relate to adjust sharpness parameters. In some examples, a printing device can include a processing resource and a memory resource storing non-transitory machine-readable instructions to cause the processing resource to receive print data comprising color channels corresponding to print pixels to be formed on a multi-layer thermally activated print medium, determine a characteristic of a corresponding layer of the multi-layer thermally activated print medium for color channels of the received print data, adjust sharpness parameters of the color channels based on the determined characteristic of the corresponding layer of the multi-layer thermally activated print medium, and cause a print head of the printing device to apply thermal energy to an area of the multi-layer thermally activated print medium including the print pixels using the adjusted sharpness parameters.

An interface circuit includes an operation controller that controls an operation state of the interface circuit; a converter that outputs divided print data signals, each divided print data signal of the divided print data signals having a predetermined bit width; a storage that stores the divided print data signals. The interface circuit includes a data controller that controls an order of writing of the divided print data signals into the storage and reading of the divided print data signals from the storage; a logical arithmetic module that performs logical arithmetic operations based on the divided print data signal and a history pulse signal and outputs a history print data signal that defines heat generating time periods of dots corresponding to print lines to be printed; and a conversion clock synchronizer that outputs the history print data signal in synchronization with a driving signal for a thermal head.

Various embodiments disclose a method for operating a printer apparatus. The method comprising monitoring a utilization rate of each heating element in a first set of heating elements defined by a print head arrangement. Further, the method comprises generating a utilization dataset based upon monitoring of the utilization rate of each heating element in the first set of heating elements print head arrangement. Furthermore, the method includes analyzing the utilization dataset to identify one or more overutilized heating elements of the first set of heating elements. Additionally, the method includes identifying a second set of heating elements defined by the print head arrangement. The second set of heating elements comprises a portion of the first set of heating elements exclusive of the one or more overutilized heating elements. The method further includes processing a print job. The processed print job utilized the second set of heating elements during printing.

Various embodiments disclose a method for operating a printer apparatus. The method comprising monitoring a utilization rate of each heating element in a first set of heating elements defined by a print head arrangement. Further, the method comprises generating a utilization dataset based upon monitoring of the utilization rate of each heating element in the first set of heating elements print head arrangement. Furthermore, the method includes analyzing the utilization dataset to identify one or more overutilized heating elements of the first set of heating elements. Additionally, the method includes identifying a second set of heating elements defined by the print head arrangement. The second set of heating elements comprises a portion of the first set of heating elements exclusive of the one or more overutilized heating elements. The method further includes processing a print job. The processed print job utilized the second set of heating elements during printing.

An example is given of a non-transitory computer-readable medium to store machine-readable instructions to be executed by a controller. The controller controls a heating element to print pixels of an image. The controller calculates an estimated thermal energy accumulation based on control of the heating element. The controller controls the heating element to print subsequent pixels based on the estimated thermal energy accumulation.

Various embodiments disclose a method for operating a printer apparatus. The method comprising monitoring a utilization rate of each heating element in a first set of heating elements defined by a print head arrangement. Further, the method comprises generating a utilization dataset based upon monitoring of the utilization rate of each heating element in the first set of heating elements print head arrangement. Furthermore, the method includes analyzing the utilization dataset to identify one or more overutilized heating elements of the first set of heating elements. Additionally, the method includes identifying a second set of heating elements defined by the print head arrangement. The second set of heating elements comprises a portion of the first set of heating elements exclusive of the one or more overutilized heating elements. The method further includes processing a print job. The processed print job utilized the second set of heating elements during printing.

Various embodiments disclose a method for operating a printer apparatus. The method comprising monitoring a utilization rate of each heating element in a first set of heating elements defined by a print head arrangement. Further, the method comprises generating a utilization dataset based upon monitoring of the utilization rate of each heating element in the first set of heating elements print head arrangement. Furthermore, the method includes analyzing the utilization dataset to identify one or more overutilized heating elements of the first set of heating elements. Additionally, the method includes identifying a second set of heating elements defined by the print head arrangement. The second set of heating elements comprises a portion of the first set of heating elements exclusive of the one or more overutilized heating elements. The method further includes processing a print job. The processed print job utilized the second set of heating elements during printing.

Various embodiments disclose a method for operating a printer apparatus. The method comprising monitoring a utilization rate of each heating element in a first set of heating elements defined by a print head arrangement. Further, the method comprises generating a utilization dataset based upon monitoring of the utilization rate of each heating element in the first set of heating elements print head arrangement. Furthermore, the method includes analyzing the utilization dataset to identify one or more overutilized heating elements of the first set of heating elements. Additionally, the method includes identifying a second set of heating elements defined by the print head arrangement. The second set of heating elements comprises a portion of the first set of heating elements exclusive of the one or more overutilized heating elements. The method further includes processing a print job. The processed print job utilized the second set of heating elements during printing.

Example implementations relate to adjust sharpness parameters. In some examples, a printing device can include a processing resource and a memory resource storing non-transitory machine-readable instructions to cause the processing resource to receive print data comprising color channels corresponding to print pixels to be formed on a multi-layer thermally activated print medium, determine a characteristic of a corresponding layer of the multi-layer thermally activated print medium for color channels of the received print data, adjust sharpness parameters of the color channels based on the determined characteristic of the corresponding layer of the multi-layer thermally activated print medium, and cause a print head of the printing device to apply thermal energy to an area of the multi-layer thermally activated print medium including the print pixels using the adjusted sharpness parameters.