Effect of quality of opto-mechanical components on fringes of diffraction Lloyd mirror interferometer

Rani, Monika; Shankar, Ajay; Kumar, Raj

doi:10.1016/j.rio.2022.100265

Cited by 3 publications

(1 citation statement)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This interferometer works on the principle of superimposing two diffracted and geometrical waves. The interference pattern obtained by this interferometer covers a large area due to the presence of diffracted light over there 9,10 . For the purpose of validating the feasibility of proposed set-up to measure step heights, metallic coated mirror, silicon mirror, and photopolymer film coated on a glass substrate with steps in coatings are used as test samples.…”

Section: Introductionmentioning

confidence: 99%

Measurement of thin film thickness using diffraction Lloyd mirror interferometer

Rani

Kumar

2023

Women in Optics and Photonics in India 2022

View full text Add to dashboard Cite

Thin films are used in many applications including holography, integrated optical circuits, polarizers, low-pass filters, beam splitters, and antireflection coatings. Refractive index and thickness of thin films are important parameters to understand its optical characteristics. In this work, thickness of thin film is measured by diffraction Lloyd mirror interferometer (DLMI). This interferometer works on the principle of superimposing two diffracted waves and direct geometric waves to generate the interference pattern. In comparison to the conventional Lloyd mirror interferometer, the interference pattern obtained by proposed interferometer covers a large area due to the presence of diffracted light in almost 4π region. The main idea of this work is to check the feasibility of DLMI to measure the thickness of films in single step. Three different test samples containing different step heights are used as a Lloyd mirror. The fringe patterns obtained from intereference of direct diffracted wavefront and reflected wavefront from samples are recorded using CMOS sensor. Recorded fringe patterns were further processed to extract phase by the application of Fourier transform. The 3D and 2D line profile of retrieved phase information are utilized to find the thickness of the film. The measured values of the thin film thickness by DLMI are compared with that of a standard mechanical profilometer. The experimental findings verify the usefulness of the proposed method.

show abstract

Section: Introductionmentioning

confidence: 99%

Measurement of thin film thickness using diffraction Lloyd mirror interferometer

Rani

Kumar

2023

Women in Optics and Photonics in India 2022

View full text Add to dashboard Cite

show abstract

Wide field 3D optical profilometry using a diffraction Lloyd’s mirror interferometer

Rani,

Kumar

2023

Appl. Opt.

View full text Add to dashboard Cite

Interference fringe projection is used as a non-contact optical profilometry method for accurate 3D measurements. In interferometric fringe projection schemes, the maximum measurable size of the test object is limited by the optics of the interferometer. In this work, we report the application of a diffraction Lloyd’s mirror interferometer (DLMI) as a wide-field sinusoidal fringe projection system for 3D shape measurement. The DLMI works on diffracted light and therefore generates interference fringes over a large area. This enables measurement of large objects using DLMI as compared to a conventional Lloyd’s mirror interferometer. The performance of the proposed system is evaluated in terms of its stability and reproducibility of the results through measurement of the standard deviation in the phase values.

show abstract

Green’s function analysis of the neutron Lloyd interferometer

Käding

Pitschmann

Abele

2023

Zeitschrift Für Naturforschung A

View full text Add to dashboard Cite

The neutron optical Lloyd interferometer can serve as a potent experiment for probing fundamental physics beyond the standard models of particles and cosmology. In this article, we provide a full Green’s function analysis of a Lloyd interferometer in the limit that the reflecting mirror extends to the screen. We consider two distinct situations: first, we will review the theoretical case of no external fields being present. Subsequently, we will analyze the case in which a gravitational field is acting on the neutrons. The latter case provides the theory necessary for using a Lloyd interferometer as a probe of gravitational fields.

show abstract

Effect of quality of opto-mechanical components on fringes of diffraction Lloyd mirror interferometer

Cited by 3 publications

References 27 publications

Measurement of thin film thickness using diffraction Lloyd mirror interferometer

Measurement of thin film thickness using diffraction Lloyd mirror interferometer

Wide field 3D optical profilometry using a diffraction Lloyd’s mirror interferometer

Green’s function analysis of the neutron Lloyd interferometer

Contact Info

Product

Resources

About