| 摘要 |
PURPOSE:To match automatically a focus of a lens to the surface of a sample by finding the >=2 maximum values from the change of reflected signals obtainable by changing the distance between a lens and sample and deciding the distance between a lens-sample to give the maximum value obtainable by the comparison among the maximum values. CONSTITUTION:A command for generation of pulse is sent to a pulse oscillator 250 so that a lens 200 and sample 220 are spaced away by a fixed distance from a microcomputer 230 and positive rotating pulses are transmitted in necessary numbers to a motor driving electric power source from the pulse oscillator 250. Similarly the maximum value is found by bringing the lens 200 close to the sample 220 and the intensity data of the reflected signals of their after motion is straged in a computer 320. Then a reverse rotating pulses are transmitted to the driving electric power source 240 and the distance between lens-sample is set up. From the intensity of variable reflected signals the distance of between lens-sample matching the focus to the surface of a sample can be automatically set up. |
