| 摘要 |
PROBLEM TO BE SOLVED: To permit the retention of quality of picture without receiving any influence of the ambient temperature by a method wherein the ambient temperature is detected to set the frequency of a pulse voltage, impressed on the piezoelectric element based on the ambient temperature. SOLUTION: When a predetermined temperature, corresponding to a set driving frequency, is optimum compared with an ambient temperature, detected by the temperature sensor of various sensor units 110, printing is effected while a head discharge driving unit 105 is driving a piezoelectric element with a set driving frequency. On the other hand, when the temperature is not optimum, the driving frequency of a print head is regulated and, thereafter, the printing is effected while the driving unit 105 is driving the piezoelectric element with the regulated driving frequency. Upon impressing a pulse voltage in this case, the driving frequency is reduced in accordance with the reduction of an ambient temperature. Accordingly, ink is supplemented so as to follow the deformation of the piezoelectric element when the temperature is low and hence the viscosity of the ink is low whereby the ink droplets can be flown without generating any thinning or lacking of the dot of ink. |
