| 摘要 |
<p>PROBLEM TO BE SOLVED: To form a required millimeter wave image in a short time by forming a rough image through high-speed scan at the first time and scanning a part of the image which is to be detailed, at a lower scan speed at the second time. SOLUTION: A millimeter wave antenna is moved right from left above an area 9 where an object can be accommodated. The antenna is moved at such a high speed that the adjacent millimetric wave beams can be detected via a slight distance. When the antenna is moved to a right end, the antenna is moved downward while returned to a left end. The process is continued until the right low beam 11 of the area 9 is detected, whereby a rough image is formed. The millimeter wave antenna is moved rightward from left above a narrow area 12 at the second scan. The antenna is moved at low speed so that the millimetric wave beams 11 can be detected in a state to overlap with one another. The antenna is moved downward while returned to the left end after moved to the right end. The process is continued until the right low millimeter wave beam 11 at the narrow area 12 is detected. A detailed image is thus formed. Since the wide area is scanned roughly at the first time and the narrow area is scanned minutely at the next time, a total time for the scan is shortened.</p> |
