| 摘要 |
<p>Petrographic characteristics, pref. the reflectance, of coal specimens are automatically determined as follows. A polished section is mounted on a microscope stage, and for 3 or more points on its surface the 3 spatial coordinates are measured by manual focussing. From these coordinates, a theoretical plane surface of the section is defined in space. In subsequent scanning of the section, the microscope is automatically focussed onto this theoretical surface, while the required property is measured from point to point. The necessary calculations can be done by computer. This type of automatic focussing does not require that the area examined reflects much light, as does a previous method.</p> |
