Absolute displacement measurements using modulation of the spectrum of white light in a Michelson interferometer

Abstract

A technique is presented for measuring small displacements by observing the frequency of spectral modulation of white light in a Michelson interferometer. An experiment is described in which the step size of a stepper-motor-driven translation stage was measured by recording the spectrum of light output from an interferometer and performing a cross-correlation calculation with theoretical spectra. Measurements made using standard laboratory-quality optical equipment were accurate to within ~10 nm for a range of over 100 microm.

Experimental Study on the Application of the Michelson Interferometer

“…Researches on the application of Michelson interferometer can improve the teaching effect, the students' experimental operation skills, and thus train the application innovation ability of the students [3][4]. Researches about thickness and refractive index measurement by Michelson interferometer has been reported in some papers [5][6][7]. Experiments of Michelson interferometer on the wavelength measurement of two kinds of laser and detecting of surface flatness for three pieces of metal sheets are introduced in this paper.…”

Single Shot White Light Interference Microscopy for 3D Surface Profilometry Using Single Chip Color Camera

“…Various interferometric techniques have been developed, among which the white light interferometric (WLI) method is the most commonly used technique for measuring the 3D-height variations and optical sectioning and surface roughness with high precision by detecting the peak position of the coherence envelope [9][10][11][12][13][14][15][16]. It is a well-established technique for absolute interferometry that can measure objects with large discontinuous gaps or isolated surfaces without any phase ambiguity of integer multiples of 2π.…”

“…In the case of white light, interference occurs only when the optical path difference (OPD) between the objective and reference beams is nearly the same (within the coherence length of the light source) so by varying one of the arms we can measure the surface roughness, small height variations and thickness of the microstructures. various schemes in WLI, such as, vertical scanning interferometry (VSI) [16,17], phase shifting interferometry (PSI) [18][19][20][21][22], fringe projection method [23][24][25][26][27], Fourier profilometry [27,28], confocal microscope [29]. In the aforementioned methods Linnik, Michelson and Mirau type interferometric objectives are used [12][13][14].…”

Unique interpretation of Talbot Bands and Fourier domain white light interferometry

“…Spectral domain white light interferometry (SDWLI) has been increasingly used for optical sensing purposes [1][2][3][4][5] as well as in optical coherence tomography (OCT). In the last five years, considerable research has been devoted to Fourier domain optical coherence tomography (FDOCT) for tissue imaging [6][7][8][9][10].…”