| 摘要 |
PURPOSE:To facilitate the confirmation of a visual field of measurement and correction to a measurable range and to measure displacement without any high- level skillfulness by expanding the visual field of measurement and judging the state in the visual field. CONSTITUTION:Variable voltage generation parts 23h and 23v apply variable voltages to deflecting coils 9 and 10 to expand the visual field of measurement by electric deflection. Arithmetic processors 20h and 20v receive a signal showing the target state in the visual field and a signal showing a preset measurement mode to make state judgements. Then, warning parts A1 and A2 generate warnings on the basis of the outputs of the devices 20h and 20v according to the displacement direction of a target or whether the set mode matches with the target or not. Therefore, whether the light part of the target is present in a set measurable direction or not and which center of the visual field of measurement the light/dark boundary of the target is present in are confirmed easily by the warnings, etc. |
