| 摘要 |
<p>PURPOSE: To install it on a stage, keeping the flatness of a sample in highly accurate condition without being influenced by the distortion of a frame entailed by the installation to the stage. CONSTITUTION: A sample W is given highly accurate flatness by at least four flatness reference bodies 16 of a board body 15 installed freely of vertical motion within a frame 10 and a clamp member 18. The frame 10 supports the sample without marring the flatness of the sample W by three height reference bodies 13 and a press means 22. Since the support of the sample W by the height reference body 13 and the press member 22 is the so-called three-point support, even if the frame 10 is distorted, it never mars the flatness of the sample W.</p> |
