Printer

A printing apparatus including a printhead which integrates M electrothermal transducers;

• a latch circuit latching printing characteristic information associated with said M electrothermal transducers;
• an input terminal inputting a plurality of pre-pulse signals, each having a different pulse width, and a plurality of main pulse signals;
• and a selector selecting a pre-pulse signal for each of M print elements on the basis of the plurality of pre-pulse signals input from said input terminal and the printing characteristic information latched by said latch circuit comprising:
• output means for outputting the printing characteristic information to said input terminal in said printhead;
• and
• application means for applying a plurality of pre-pulse signals and main pulse signals to said printhead,
• wherein said printhead performs a preheating operation by sending electricity to said M electrothermal transducers by using the pre-pulse signals selected by said selector, and performs a printing operation by selectively applying the main pulse signal to said M electrothermal transducers after the preheating operation.

A printing apparatus for generating print image data by receiving print image data from an external device, and printing an image on a recording medium on the basis of the print image data by using a printhead having a plurality of print elements, and driving said plurality of print elements by using N driving circuits, comprising:

• division control means for dividing said N driving circuits into M groups and performing control in units of groups;
• temperature measurement means for measuring a temperature of said printhead for each of the groups;
• driving means for driving said printhead through said N driving circuits to perform a print operation by applying a first pulse to each of said plurality of print elements, and applying a second pulse following the first pulse, wherein an interval time exists between the application of the first pulse and the application of the second pulse;
• first adjustment means for adjusting a width of the second pulse for each of said N driving circuits on the basis of variations in printing operations of said plurality of print elements;
• and
• second adjustment means for adjusting the interval time on the basis of M temperatures measured by said temperature measurement means.

A printing apparatus for printing an image by using a printhead in which a plurality of electrothermal transducers are arrayed, and ink is discharged from a plurality of orifices by driving the plurality of electrothermal transducers, comprising:

• a pre-pulse generation circuit for generating a pre-pulse to be applied to the plurality of electrothermal transducers so as to generate thermal energy insufficient to discharge ink;
• a main-pulse generation circuit for generating a main-pulse to be applied to the plurality of electrothermal transducers so as to generate thermal energy causing ink to be discharged;
• a driving circuit for driving said printhead by selectively applying the main-pulse to the plurality of electrothermal transducers, based on an image signal;
• and
• a pre-pulse supply control circuit for controlling a supply of the pre-pulse, generated by said pre-pulse generation circuit, to said printhead, based on an input of a predetermined signal,
• wherein said pre-pulse supply control circuit controls a switching between a mode in which the pre-pulse is applied to the plurality of electrothermal transducers regardless of selective driving of the plurality of electrothermal transducers based on the image signal, and another mode in which the pre-pulse is applied to the electrothermal transducer to which the main-pulse is applied.

A drive control circuit for driving a printhead in which a plurality of electrothermal transducers are arrayed, and ink is discharged from a plurality of orifices, comprising:

• a pre-pulse generation circuit for generating a pre-pulse to be applied to the plurality of electrothermal transducers so as to generate thermal energy insufficient to discharge ink;
• a main-pulse generation circuit for generating a main-pulse to be applied to the plurality of electrothermal transducers so as to generate thermal energy causing ink to be discharged;
• a driving circuit for driving said printhead by selectively applying the main-pulse to the plurality of electrothermal transducers, based on an image signal;
• and
• a pre-pulse supply control circuit for controlling a supply of the pre-pulse, generated by said pre-pulse generation circuit, to said printhead, based on an input of a predetermined signal,
• wherein said pre-pulse supply control circuit controls a switching between a mode in which the pre-pulse is applied to the plurality of electrothermal transducers regardless of selective driving of the plurality of electrothermal transducers based on the image signal, and another mode in which the pre-pulse is applied to the electrothermal transducer to which the main-pulse is applied.

An image forming apparatus for forming an image by using a printhead in which a plurality of electrothermal transducers are arrayed, and ink is discharged from a plurality of orifices by driving the plurality of electrothermal transducers, comprising:

• a pre-pulse generation circuit for generating a pre-pulse to be applied to the plurality of electrothermal transducers so as to generate thermal energy insufficient to discharge ink;
• a main-pulse generation circuit for generating a plurality of main-pulses, having widths different from each other, to be applied to the plurality of electrothermal transducers so as to generate thermal energy causing ink to be discharged;
• a memory for storing characteristic information corresponding to each of the plurality of electrothermal transducers;
• a driving circuit for driving said printhead by selectively applying the pre-pulse and one of the plurality of the main-pulses to the plurality of electrothermal transducers, based on an image signal;
• detection means for detecting a temperature distribution in a arrayed direction of the plurality of electrothermal transducers in said printhead;
• and
• adjustment means for adjusting an interval time between a pre-pulse and the main-pulse to be applied to each of the plurality of electrothermal transducers, based on the temperature distribution detected by said detection means,
• wherein said driving circuit selectively applies one of the plurality of main-pulses, based on the characteristic information, after the pre-pulse has been applied and the interval time has passed.