| 摘要 |
PURPOSE:To enable the flying angles of ink particles at a plurality of jetting ports to be automatically inspected at a time, by a method wherein, an angle between a long principal axis of an equivalent ellipse of a flying ink particle and a reference line is compared with a reference angle prestored in a computer to be detected for inspection. CONSTITUTION:Ink particles 8 are simultaneously jetted out of jetting ports 7 at a time, and a stroboscope 9 is emitted to lead a video signal of a TV camera 10 into a signal processing circuit 21. This signal is once stored in a video RAM 22-1 to obtain a still picture. The presence of data 1 is judged with the value above a prestored reference level value; the absence of data 0 is judged with the value below the reference level value. Then, the judgement is stored in a RAM 22-2 serving as a work area. After that, the value of the video signal is stored in a memory 22 in still picture form, and this is calculated by a computer 23 to obtain an equivalent ellipse 25 surrounded by a circumscribing line 28, an angle phi between a long principle axis 26 of the equivalent ellipse and a reference line 27 is calculated, the resulting angle is detected by the comparison with a reference ink particle flying angle which was prestored in the computer 23, and the resulting value is displayed by an output device 24. |
