title: Simultaneous three-dimensional step-height measurement and high-resolution tomographic imaging with a spectral interferometric microscope.
abstract: A noncontact, nonmechanical scanning, wide-field spectral interference microscope is developed for simultaneous measurement of three-dimensional step-height of discontinuous objects and tomographic imaging. A superluminescent diode (SLD) is used as a broadband light source and a liquid-crystal Fabry-Perot interferometer (LC-FPI) as a frequency-scanning device. By means of changing the injection current to the SLD, the spectral profile of the SLD is equalized, and a constant light input to the interferometer is achieved over the entire frequency-scan range. The Fourier-transform technique is used to determine both the amplitude and the phase of spectral fringe signals. Three-dimensional height distribution of a discontinuous object is obtained from the phase information, whereas optically sectioned images of the object are obtained either from the amplitude information alone or from the combination of both the amplitude and phase information. Experimental results with submicrometer resolution are presented for both step-height measurement and tomographic sectioning.
authors.affiliation: University of Electro-Communications, Chofu, Tokyo, Japan.
authors.forename: Dalip Singh
authors.initials: DS
authors.lastname: Mehta
authors.forename: Masaya
authors.initials: M
authors.lastname: Sugai
authors.forename: Hideki
authors.initials: H
authors.lastname: Hinosugi
authors.forename: Shohei
authors.initials: S
authors.lastname: Saito
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Takeda
authors.forename: Takashi
authors.initials: T
authors.lastname: Kurokawa
authors.forename: Hideki
authors.initials: H
authors.lastname: Takahashi
authors.forename: Masahito
authors.initials: M
authors.lastname: Ando
authors.forename: Masataka
authors.initials: M
authors.lastname: Shishido
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Yoshizawa
mesh_terms: D021621:Imaging, Three-Dimensional; D008857:Microscopy, Interference; D008962:Models, Theoretical; D012815:Signal Processing, Computer-Assisted; D014054:Tomography