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Pramod Rastogi

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Publications associées (111)

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Simultaneous estimation of unwrapped phase and phase derivative from a closed fringe pattern

Pramod Rastogi, Rishikesh Dilip Kulkarni

We propose a new approach for the direct estimation of the unwrapped phase from a single closed fringe pattern. The fringe analysis is performed along a given row/column at a time by approximating the phase with a weighted linear combination of linearly in ...

2016

Phase estimation in digital holographic interferometry using cubic phase function based method

Pramod Rastogi, Sai Siva Gorthi

The paper introduces a cubic-phase-function based method to estimate interference phase in digital holographic interferometry. The proposed method relies on piecewise polynomial approximation of phase by dividing an arbitrary row/column of the complex reco ...

Taylor & Francis2010

Estimation of Phase and Its Higher Order Derivatives from a Single Complex Interferogram

Pramod Rastogi, Rishikesh Dilip Kulkarni

This paper reports a method for the simultaneous estimation of unwrapped phase and higher order phase derivatives from a single phase fringe pattern recorded in an optical interferometric setup, thereby overcoming substantial barriers to achieving such mea ...

2016

Phase estimation from noisy phase fringe patterns using linearly independent basis functions

Pramod Rastogi, Rishikesh Dilip Kulkarni

A novel technique is proposed for obtaining unwrapped phase estimation from a highly noisy exponential phase field. In this technique, the interference phase is represented as a linear combination of linearly independent and pre-defined basis functions alo ...

Iop Publishing Ltd2015

Acquisition of multiple phase derivatives from a single frame in digital holographic interferometry

Pramod Rastogi, Rishikesh Dilip Kulkarni

This paper proposes a technique to extract two-dimensional multiple phase derivatives (strains, slopes, and shearing strains) from a single frame of the interference fringe pattern recorded in an optical setup with multiple illumination beams. In the propo ...

Spie-Soc Photo-Optical Instrumentation Engineers2015

Multiple phase derivative estimation using autoregressive modeling in holographic interferometry

Pramod Rastogi, Rishikesh Dilip Kulkarni

A novel technique is proposed for the direct and simultaneous estimation of multiple phase derivatives from a deformation modulated carrier fringe pattern in a multi-wave holographic interferometry set-up. The fringe intensity is represented as a spatially ...

IOP Publishing2015

High-Resolution Frequency Estimation Technique for Recovering Phase Distribution in Interferometers

Pramod Rastogi, Abhijit Patil, Rajesh Langoju

An integral approach to phase measurement is presented. First, the use of a high-resolution technique for the pixelwise detection of phase steps is proposed. Next, the robustness of the algorithm that is developed is improved by incorporation of a denoisin ...

OSA2005

Patch-wise denoising of phase fringe patterns based on matrix enhancement

Pramod Rastogi, Rishikesh Dilip Kulkarni

We propose a new approach for the denoising of a phase fringe pattern recorded in an optical interferometric setup. The phase fringe pattern which is generally corrupted by high amount of speckle noise is first converted into an exponential phase field. Th ...

2016

Fringe demodulation using the two-dimensional phase differencing operator

Pramod Rastogi, Rajshekhar Gannavarpu

The Letter proposes a method for phase estimation from a fringe pattern. The proposed method relies on a parametric approach where the phase is locally approximated as a two-dimensional (2D) polynomial, with the ensuing polynomial coefficients as the respe ...

Optical Society of America2012

Piecewise polynomial phase approximation approach for the analysis of reconstructed interference felds in digital holographic interferometry

Pramod Rastogi, Sai Siva Gorthi

This paper proposes a new approach for the analysis of reconstructed interference fields in digital holographic interferometry. In the proposed approach the interference phase to be estimated is conceived as a piecewise polynomial signal; consequently, eac ...

Institute of Physics2009

Simultaneous estimation of phase and its pth order derivatives

Pramod Rastogi, Rishikesh Dilip Kulkarni

One unaddressed challenge in optical metrology has been the measurement of higher order derivatives of rough specimens subjected to loading. In this paper, we investigate an approach that allows for the simultaneous estimation of the phase and its higher o ...

2016

Comparative Study of Three Bayesian Filtering Approaches for Phase Step Estimation in Optical Interferometry

Pramod Rastogi, Abhijit Patil

This paper presents three recursive Bayesian filtering approaches in phase shifting interferometry involving a piezoelectric device (PZT). The three approaches are extended Kalman filtering, unscented Kalman filtering, and particle filtering. These approac ...

2010

Estimation of phase derivative using adaptive window spectrogram

Pramod Rastogi, Sai Siva Gorthi, Rajshekhar Gannavarpu

The paper introduces an adaptive-window-spectrogram-based method to directly estimate the phase derivative from a single fringe pattern. The proposed method relies on estimating the phase derivative using spectrogram peak detection for a set of different w ...

2010

Estimation of dynamically varying displacement derivatives using fringe projection technique

Pramod Rastogi, Sai Siva Gorthi, Rajshekhar Gannavarpu

This paper presents a pseudo Wigner–Ville-distribution-based method in fringe projection for analyzing temporal behavior of the displacement derivative for a continuously deformed object. In the proposed method, a computer generated fringe pattern is proje ...

Optical Society of America2011

Estimation of Phase in Fringe Projection Technique Using High-order Instantaneous Moments Based Method

Pramod Rastogi, Sai Siva Gorthi, Rajshekhar Gannavarpu

For three-dimensional (3D) shape measurement using fringe projection techniques, the information about the 3D shape of an object is encoded in the phase of a recorded fringe pattern. The paper proposes a high-order instantaneous moments based method to est ...

AIP Conf. Proc.2010

Estimation of displacement derivatives in digital holographic interferometry using a two-dimensional space-frequency distribution

Pramod Rastogi, Sai Siva Gorthi, Rajshekhar Gannavarpu

The paper introduces a two-dimensional space-frequency distribution based method to directly obtain the unwrapped estimate of the phase derivative which corresponds to strain in digital holographic interferometry. In the proposed method, a two-dimensional ...

Optical Society of America2010

Correcting spherical aberrations induced by an unknown medium through determination of its refractive index and thickness

Pramod Rastogi

In imaging and focusing applications, spherical aberration induces axial broadening of the point spread function (PSF). A transparent medium between lens and object of interest induces spherical aberration. We propose a method that first obtains both the p ...

Optical Society of America2011

Matrix pencil based phase derivative estimation in digital holographic interferometry

Pramod Rastogi, Rishikesh Dilip Kulkarni

A novel technique is proposed for the direct two-dimensional phase derivatives estimation based on the matrix pencil approach in digital holographic interferometry. The interference field is represented as a two-dimensional complex sinusoidal signal in an ...

Iop Publishing Ltd2015

Simultaneous measurement of in-plane and out-of-plane displacements using pseudo-Wigner-Hough transform

Pramod Rastogi, Rishikesh Dilip Kulkarni

A new method based on pseudo-Wigner-Hough transform is proposed for the simultaneous measurement of the in-plane and out-of-plane displacements using digital holographic moire. Multiple interference phases corresponding to the in-plane and out-of-plane dis ...

Optical Society of America2014

Two-step phase demodulation algorithm based on quadratic phase parameter estimation using state space analysis

Pramod Rastogi, Rishikesh Dilip Kulkarni

We propose a noise robust two-step phase shifting algorithm for the evaluation of random and unknown phase step. In this algorithm, the phase within a small size two-dimensional window around a user selected pixel in an interferogram is approximated as a q ...

2018