| 摘要 |
PURPOSE:To allow gradation recording to be performed and printing speed to be set at the same level as when gradation recording is not performed in a normal operation mode by entering an independent energy-level signal in at least two independent areas and permitting a single bubble to generate by a combination of said signals and its size to change. CONSTITUTION:A heat-generating element section is, for instance, divided in two elements 19a, 19b, and these are allowed to drive independently by means of their respective control electrodes. Signals E1, E2 are so timed as to enter the two heat-generating elements 19a, 19b almost simultaneously to generate a single bubble. It is possible to generate bubbles of different sizes by combining the values of E1 and E2. Accordingly, the size of ink droplets to be discharged changes and the diameter of pixels can be changed to enable gradation recording. Both heat-generating elements are caused to drive concurrently, so that bubble production time can be shortened and discharge response speed be increased. At the same time, the gradation recording can be achieved at almost the same speed as the non-gradation recording. |
