| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and a system for measuring jet characteristic of ink drops whereby ink drops to be measured are surely specified from a picked-up image and a jet characteristic of the ink drops can be measured highly accurately. SOLUTION: Images of an ink drop 5 jetted from a nozzle hole which are picked up at a delay reference time after a fixed time from a jet start and at a delay increase time after a fixed time from the delay reference time are processed, thereby specifying positions of an object to be picked up at the delay reference time and at the delay increase time. Whether or not the object to be picked up is the ink drop 5 a jet characteristic of which is to be measured is judged on the basis of a relative positional relationship of the object to be picked up at the delay reference time and at the delay increase time. When the positions of the object to be picked up at the delay reference time and delay increase time are within a range of a movement amount corresponding to a jet speed, it is so judged that the object to be picked up is the ink drop 5. If the positions are outside the range, the object to be picked up is judged not to be the liquid drop 5. |
