Claims
- 1. A printing apparatus which performs printing by moving a printing head, having a plurality of printing elements, relative to a printing medium, said apparatus comprising:
- scanning means for moving the printing head over the printing medium so as to perform the printing, said scanning means accelerating the printing head to a predetermined speed in an accelerating speed area, moving the printing head at the predetermined speed in a constant speed area and decelerating the printing head from the predetermined speed in a decelerating speed area;
- detection means for detecting the speed of the printing head relative to the printing medium in the accelerating speed area, constant speed area and decelerating speed area;
- timing determination means for determining a timing to drive the printing head in accordance with the speed detected by said detection means; and
- printing means for printing by driving the printing head in accordance with the timing determined by said timing determination means, the printing head being enabled for driving in the accelerating speed area, the constant speed area and the decelerating speed area,
- wherein said printing means divides the plurality of printing elements into a plurality of blocks and sequentially drives each of the plurality of blocks of the printing elements in a driving period, and said timing determination means determines driving timing of each of the plurality of blocks of the printing elements and changes time intervals between the driving timing of each of the plurality of blocks of the printing elements in the driving period in accordance with the speed of the printing head detected by said detection means, each of the time intervals between the driving timings in the accelerating speed area and the decelerating speed area being longer than each of the time intervals in the constant speed area, and a driving period of each of the plurality of blocks of the printing elements is constant in each of the accelerating speed area, the constant speed area and the decelerating area.
- 2. The apparatus according to claim 1, wherein said detection means detects the speed of the printing head by detecting that the printing head passes a slit of an encoder provided in a scanning area.
- 3. A printing apparatus according to claim 1, wherein said detection means comprises a scale having a plurality of slits formed in a predetermined pitch and a sensor for detecting each of said plurality of slits on the scale, and said detection means detects the speed of the printing head in accordance with a detection of each of said plurality of slits by said sensor which is moving with the printing head.
- 4. A printing apparatus according to claim 1, wherein said timing determination means comprises storage means for prestoring timing data concerning a driving timing of the printing head, the timing data being defined to conform the driving timing of the printing head to the speed of the printing head, and said timing determination means reads the timing data from the storage means and said printing means drives the printing head at a printing timing in accordance with the timing data.
- 5. A printing apparatus according to claim 1, wherein the printing head comprises an ink jet printing head including electrothermal transducers for heating and ejecting ink.
- 6. A printing apparatus according to claim 1, wherein the printing head comprises plural printing units, each of the plurality of printing units for printing with a different color.
- 7. A printing apparatus according to claim 6, wherein each of the plurality of printing units comprises an ink jet printing unit including electrothermal transducers for heating and ejecting ink.
Priority Claims (1)
Number |
Date |
Country |
Kind |
5-175148 |
Jul 1993 |
JPX |
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Parent Case Info
This application is a continuation of application Ser. No. 08/274,794 filed Jul. 14, 1994, now abandoned.
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Continuations (1)
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Number |
Date |
Country |
Parent |
274794 |
Jul 1994 |
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