Printing apparatus, printing method, and printing program

Abstract

To provide a printer, a printing method, and a printing program which easily increase density in a main scan direction of dots formed on a printing medium, and thereby can print a high quality printing image.SOLUTION: A printer extracts an object pixel adjacent to printing pixels among non-printing pixels (S15). The printer divides the extracted object pixel in a main scan direction, and thereby generates a divided pixel (S17). The printer specifies a second printing image in which the divided pixel closer to the printing pixel adjacent to the object pixel among the divided pixels is added as a divided printing element to the printing elements (S21). The printer generates second printing data for printing the second printing image (S23). The printer sets the value of power supplied to a heating element as a first value at a position corresponding to the printing pixels, and sets the value of the power supplied to the heating element at a second value smaller than the first value at a position corresponding to the object pixel (S29 and S33).SELECTED DRAWING: Figure 7

Claims

1. A thermal head in which multiple heating elements are arranged in the main scanning direction, A moving mechanism that moves the printing medium relative to the thermal head in a sub-scanning direction perpendicular to the main scanning direction, A control unit that controls the thermal head and the moving mechanism, A storage unit stores first print data for printing a first print image, which is a print image represented by the print pixels, and sets print pixels, which are pixels on which dots are formed by the heat generated by the heating element, and non-print pixels, which are pixels on which no dots are formed, among the pixels arranged in the main scanning direction and the sub-scanning direction. A printing apparatus equipped with, The control unit, A generation process for generating second print data based on the first print data stored in the storage unit, Among the non-printed pixels, target pixels are extracted that are adjacent to a printed pixel on one or the other side of the sub-scanning direction, and that are adjacent to a printed pixel on one or the other side of the main scanning direction. The extracted target pixel is divided into n (where n is an integer of 2 or more) in the main scanning direction to generate n divided pixels. Of the n division pixels, at least one division pixel is selected from the n division pixels in order from the side closest to the target pixel in the main scanning direction, and this selection is used as a division printing pixel on the print pixel where a dot is formed, thereby identifying a second print image which is a print image in which the division pixels are selected as a division printing pixel. Generate the second print data for printing the second print image. The above generation process and, A control process that controls the thermal head and the moving mechanism based on the second print data generated by the generation process, The value of the energy applied to the heating element in order to generate heat at a position corresponding to the printed pixel in the printed medium is defined as the first value. The value of the energy applied to the heating element in order to generate heat at the position corresponding to the target pixel in the printing medium is set to a second value which is smaller than the first value. The control process and A printing apparatus characterized by performing the following actions.

2. The aforementioned control process is The printing apparatus according to claim 1, characterized in that, when n is equal, the second value is increased as the number of divided printing pixels increases.

3. The aforementioned control process is The printing apparatus according to claim 1, characterized in that, when the number of divided printing pixels is the same, the larger n is, the smaller the second value is.

4. The control process is performed based on the second print data, The first value is defined as the energy applied to the heating element in order to generate heat at the position where the printed pixels in the second printed image are located on the printing medium. The second value is defined as the energy applied to the heating element in order to generate heat at the position where the target pixels, including the divided print pixels in the second print image, are located on the print medium. The printing apparatus according to feature 1.

5. The control process is performed based on the first print data and the second print data. The value of energy applied to the heating element in order to generate heat at the positions on the printing medium where the first printed image and the second printed image are arranged is defined as the first value. The second value is defined as the energy applied to the heating element in order to generate heat at a position on the printing medium where only the second printed image is placed. The printing apparatus according to feature 1.

6. The pixels in the first print data are The original pixels, each having the same length in the main scanning direction and the sub-scanning direction, are generated by dividing them into m (where m is an integer of 2 or more) in the sub-scanning direction. The length of the sub-scanning direction is 1 / m of the length of the main scanning direction. The printing apparatus according to feature 1.

7. The printing apparatus according to claim 1, characterized in that n is 2.

8. The aforementioned heating element is The heating element forms a single dot on the printing medium by generating heat, and consists of two heating elements separated in the main scanning direction. The printing apparatus according to feature 1.

9. If energy exceeding a predetermined value is applied to the heating element and generates heat, dots are formed on the printing medium; if energy less than the predetermined value is applied to the heating element and generates heat, no dots are formed on the printing medium. The printing apparatus according to claim 1, characterized in that the second value is greater than or equal to the predetermined value.

10. The control unit, The first value is defined as the energy applied to the heating element in order to generate heat at a position corresponding to a portion of the printed pixels in the printed medium. The printing apparatus according to claim 1, characterized in that the value of the energy applied to the heating element in order to heat the heating element at a position corresponding to a portion of the printed pixel excluding a portion is set to the second value, thereby dividing the dots formed at a position corresponding to a portion of the printed pixel excluding a portion of the printed medium in the main scanning direction.

11. The control unit, The printing apparatus according to claim 1, characterized in that the dots formed on the printing medium are divided in the sub-scanning direction by shortening the period during which energy is applied to the heating element to cause the heating element to generate heat.

12. A generation step in which, among pixels arranged in a main scanning direction and a sub-scanning direction orthogonal to the main scanning direction, printed pixels are defined as pixels on which dots are formed by the heat generated by the heating elements of a thermal head in which a plurality of heating elements are arranged in the main scanning direction, and non-printed pixels are defined as pixels on which no dots are formed, and second print data is generated based on first print data for printing a first print image which is a print image represented by the printed pixels, Among the non-printed pixels, target pixels are extracted that are adjacent to a printed pixel on one or the other side of the sub-scanning direction, and that are adjacent to a printed pixel on one or the other side of the main scanning direction. The extracted target pixel is divided into n (where n is an integer of 2 or more) in the main scanning direction to generate n divided pixels. Of the n division pixels, a second printed image is identified, which is a printed image in which at least one of the division pixels, starting from the side closest to the target pixel in the main scanning direction, is added to the print pixel as a division print pixel on which a dot is formed. Generate the second print data for printing the second print image. The above generation step, A control step that controls the thermal head and a movement mechanism for moving the printing medium relative to the thermal head in the sub-scanning direction, based on the second print data generated by the generation step, The value of the energy applied to the heating element in order to generate heat at a position corresponding to the printed pixel in the printed medium is defined as the first value. The energy value applied to the heating element in order to generate heat at the position corresponding to the target pixel in the printing medium is set to a second value which is smaller than the first value. The control step and A printing method characterized by comprising the following features.

13. A computer for a printing apparatus comprising: a thermal head with multiple heating elements arranged in the main scanning direction; a moving mechanism that moves the printing medium relative to the thermal head in a sub-scanning direction perpendicular to the main scanning direction; and a storage unit that stores first print data for printing a first print image, which is a print image represented by the printed pixels, where printed pixels are defined as pixels on which dots are formed by the heat generated by the heating elements and non-printed pixels on which dots are not formed, among the pixels arranged in the main scanning direction and the sub-scanning direction; A generation step of generating second print data based on the first print data stored in the storage unit, Among the non-printed pixels, target pixels are extracted that are adjacent to a printed pixel on one or the other side of the sub-scanning direction, and that are adjacent to a printed pixel on one or the other side of the main scanning direction. The extracted target pixel is divided into n (where n is an integer of 2 or more) in the main scanning direction to generate n divided pixels. Of the n division pixels, a second printed image is identified, which is a printed image in which at least one of the division pixels, starting from the side closest to the target pixel in the main scanning direction, is added to the print pixel as a division print pixel on which a dot is formed. Generate the second print data for printing the second print image. The above generation step, A control step that controls the thermal head and the moving mechanism based on the second print data generated by the generation step, The value of the energy applied to the heating element in order to generate heat at a position corresponding to the printed pixel in the printed medium is defined as the first value. The energy value applied to the heating element in order to generate heat at the position corresponding to the target pixel in the printing medium is set to a second value which is smaller than the first value. The control step and A printing program to execute this.

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