| 摘要 |
PURPOSE:To facilitate the setting of the opened port of a mask by constituting the viewfield restricting mask from a transparent material for the visible light and from a nontransparent material for infrared rays and carrying out positioning, observing the whole of a sample image. CONSTITUTION:The light which is reflected from a sample 6 and passes through the sample 6 forms an image at the position of a mask 7 on an objective mirror 6. The image is covered by the mask 7, and only the light which passes through the opened port of the mask 7 is measured by a light measuring element 11, passing through plane mirrors 8 and 9 and a concave mirror 10. When the positioning for the opened port is performed, positioning can be carried out easily observing the whole of the sample 6, since the mask 7 is transparent for the visible light, and can achieve the function as mask, since the mask is nontransparent for infrared rays. |
