| 摘要 |
PURPOSE:To make desired liquid drips be discharged steadily from the orifices made at the tip of actuating chambers by providing an imaging optical system whereby the strength of a beam spot scanning the plural number of acting chambers of a liquid drip jet member is made almost uniform. CONSTITUTION:A photobeam from a laser oscillator 1 is modulated in strength by a modulation deflector 3 in accordance with an input signal and the photobeam thus modulated and deflected is then swept in the main scanning direction by a deflector 5. Next, after being converged by an imaging lens 7, the photobeam is shifted in direction by a mirror 8 and is formed into an image at the fixed place of an ink conduit (acting chamber) 10 formed in a glass board 13 of a liquid drip jet member 9, thereby making liquid drips be discharged from orifices 11. At this time, by setting the coefficient of aberration of distortion of the imaging lens 7 in the range between 2/3 and 1, the strength of the pbotobeam spot scanning the actuating chambers 10 can be made almost uniform. |
