| 摘要 |
PROBLEM TO BE SOLVED: To well detect ink being ejected from the nozzle of an ink jet head. SOLUTION: The detector for detect ink being ejected from the nozzle 9 of an ink jet head 8 comprises a laser diode 2 for irradiating the flying path of ink ejected from the nozzle 9 with a laser beam, and a photodiode 3 for receiving the laser beam projected from the laser diode 2 and passed through the flying path and producing an output signal corresponding to the quantity of received light. |
