摘要 |
A method and apparatus for generating and detecting changes in interference patterns such as may be used to measure small displacements. A collimated beam is diffracted to produce a standing wavefront along a surface. The surface is coincident with the surface of a device which emits a signal in response to changes in the intensity of the wave front. In one embodiment, the diffracting means is a grating and the signal emitting means includes a beam splitter that generates an interference pattern responsive to the intensity of the wave front. In another embodiment, the signal emitting means is a membrane that emits a signal in response to changes in the wavefront. The apparatus and method can be used in applications which include measurement of displacement and measurement of force in which no displacement takes place.
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