Spectral modulation interferometry for quantitative phase imaging

Abstract

Abstract:We propose a spectral-domain interferometric technique, termed spectral modulation interferometry (SMI), and present its application to high-sensitivity, high-speed, and speckle-free quantitative phase imaging. In SMI, one-dimensional complex field of an object is interferometrically modulated onto a broadband spectrum. Full-field phase and intensity images are obtained by scanning along the orthogonal direction. SMI integrates the high sensitivity of spectral-domain interferometry with the high speed of spectral modulation to quantify fast phase dynamics, and its dispersive and confocal nature eliminates laser speckles. The principle and implementation of SMI are discussed. Its performance is evaluated using static and dynamic objects.

In situ quantitative topographic measurement and corrosion behaviour of low carbon steel in chloride solutions

“…The outcome interference spectra are then recorded using a custom spectrometer. Numerical reconstruction of each interference spectra produces an amplitude-contrast image (similar to the image captured by the conventional reflection mode-optical microscope) and a phase-contrast image that contains the surface height information [57,58]. In this configuration, the rapid collection of temporally- and spatially resolved phase data provides the necessary information to reconstruct dynamic surface topography features.…”

“…The SMI technique offers sub-nanometre vertical precision, sub-micrometre lateral resolution, high-speed image acquisition (up to 120 Hz) and speckle-free phase imaging using a Linnik interferometer [54,57]. SMI uses a broadband light beam from a super-luminescent diode (SLD, Superlum; wavelength, λ = 837 nm, Δλ = 54 nm).…”

Optical Imaging and Characterization of Graphene and Other 2D Materials Using Quantitative Phase Microscopy

“…We introduce the basic principle of QLSI. We have chosen to use this phase and intensity measurement technique, but other techniques that quantitatively measure the scalar electromagnetic field in a nonbiased and halo-free manner could also be applied for investigation of the optical properties of 2D materials including, for example, digital holography and related techniques − or external reference-free approaches. − …”

Beating temporal phase sensitivity limit in off-axis interferometry based quantitative phase microscopy

“…protein aggregation [5], virus particle dynamics [6] and spiking-induced membrane fluctuations [7]) without exogenous labelling is very challenging with conventional QPM methods due to the low signal-to-noise-ratio (SNR). Many factors can contribute to noise during phase measurements, such as photon shot-noise, electronic source (e.g., device instability, camera noise, and quantization errors), light source instability, coherence properties, and other environmental factors (e.g., mechanical vibrations and air-density variations) [8][9][10][11][12].…”