Two-wavelength double heterodyne interferometry using a matched grating technique.
نویسندگان
چکیده
Two-wavelength double heterodyne interferometry is applied for topographic measurements on optically rough target surfaces. A two-wavelength He-Ne laser and a matched grating technique are used to improve system stability and to simplify heterodyne frequency generation.
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عنوان ژورنال:
- Applied optics
دوره 30 22 شماره
صفحات -
تاریخ انتشار 1991