发明名称 |
Circuit for image displacement in a particle beam apparatus independently of magnification |
摘要 |
A circuit includes an inversely fedback operational amplifier having a saw tooth deflection signal applied at its input, as well as a coil pair and an output for deflecting the particle beam of a scanning microscope within a scanned field as established by the coil current. A plurality of resistor elements are selected by a switch and a constant current source for feeding a direct current is provided to effect the image displacement at a connection P between the coil pair and respective one of the resistor elements. Since the direct current flows only through the coils but not through the resistor elements as a consequence of the feedback amplifier, image displacement is independent of magnification established by the respective resistor element.
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申请公布号 |
US4891523(A) |
申请公布日期 |
1990.01.02 |
申请号 |
US19880260581 |
申请日期 |
1988.10.21 |
申请人 |
SIEMENS AKTIENGESELLSCHAFT |
发明人 |
SCHMITT, REINHOLD |
分类号 |
H01J37/22;G01Q30/02;H01J37/04;H01J37/147;H01J37/28 |
主分类号 |
H01J37/22 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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