Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of the Optical Society of America A

Young’s interference experiments with a laser filamentary light source

Mónica E. Manceñido, Gustavo Pozzi, Luciano Zunino, M. Garavaglia

Published Nov 1, 1999• 1 citation
Publisher

Abstract

We used the focal line of a cylindrical lens illuminated by a collimated expanded He–Ne red laser light as a filamentary light source to observe Young’s interference fringes. When the monochromatic filamentary light source is parallel to Young’s slits, the interference fringes are parallel to them and are well defined and highly contrasted. When the filamentary light source is rotated in a plane parallel to that of the slits, the visibility of the interference fringes is always extremely high, but their geometrical distribution and the distance between them depend on the rotation angle and the observation distance. A simple theoretical model is proposed, based on a cylindrical wave propagated according to the Huygens–Kirchhoff formula. The experimental results coincide remarkably well with the stated theoretical model.

DOI
10.1364/josaa.16.002767

Related papers

Subtleties with Young's double-slit experiment: Investigation of spatial coherence and fringe visibility

David P. Jackson, Natalie G. Ferris, Ruthie Strauss +2 more

We discuss Young's double-slit experiment using a partially coherent light source consisting of a helium-neon laser incident on a rotating piece of white paper. Such an experiment is appropriate for undergraduate students as an independent project or as part of an advanced lab course. As is well known, the resulting interference pattern is observed to disappear and return, depending on the angular size of the source. Interestingly, while the standard theoretical prediction for the light intensity agrees quite well with experimental data when the fringe visibility is high, the prediction is noticeably off when the visibility is low. A first-principles calculation of the light intensity is performed and shown to agree extremely well with the experimental results for all visibilities.

American Journal of Physics•Aug 23, 2018•18 citations

Controlling the degree of visibility of Young’s fringes with photon coincidence measurements

P. H. Souto Ribeiro, Sebastião Pádua, J. C. Machado da Silva +1 more

Is it possible to detect the interference from an extended incoherent source with Young's slits when the source-slits distance is such that all dimensions of the coherence area of the incident light beam are smaller than the distance between the slits? We have experimentally demonstrated that, under the above conditions, interference fringes can be obtained with a controlled degree of visibility by means of coincidence measurements between conujugated beams of the down-conversion luminescence.

Physical Review A•May 1, 1994•145 citations

Control of Young’s fringes visibility by stimulated down-conversion

P. H. Souto Ribeiro, Sebastião Pádua, J. C. Machado da Silva +1 more

The stimulated parametric-down-conversion luminescence is used as a light source with controlled spatial coherence. Performing the double-slit Young experiment, we show that the interference-pattern visibilities can be controlled by varying the inducing laser intensity. The results indicate that down-conversion light statistics change during this variation. A simple theoretical description is also shown.

Physical Review A•Feb 1, 1995•20 citations

A Theoretical Reformulation of the Classical Double Slit Interference Experiment

Joseph Ivin Thomas

In 1801, Thomas Young devised what is now known as the Classical Double Slit Experiment. In this experiment, light waves emanating from two separate sources, interfere to form a pattern of alternating bright and dark fringes on a distant screen. By measuring the position of individual fringe centers, the fringe widths and the variation of average light intensity on the screen, it is possible to compute the wavelength of light itself. The original theoretical analysis of the experiment employs a set of geometric assumptions which are collectively referred to here as the Parallel Ray Approximation. Accordingly, any two rays of light arising from either source and convergent on an arbitrary point on the screen, are considered very nearly parallel to each other in the vicinity of the sources. This approximation holds true only when the screen to source distance is very large and the inter-source distance is much larger than the wavelength of light. The predictions that naturally follow are valid only for fringes located near the center of the screen (e.g. the equal spacing of fringes). But for those fringes located further away from the screen center, the precision of these predictions rapidly wanes. Also when the screen to source distance is comparable to the inter-source separation or when the inter-source distance is comparable to the wavelength of light, the original analysis is no longer applicable. In this paper, the theoretical foundations of Young’s experiment are re-formulated using a newly derived analytical equation of a hyperbola, which forms the locus of the points of intersections of two expanding circular wavefronts (with sources located at the respective centers of expansion). The ensuing predictions of the new analysis are compared with those of the old. And finally, it is shown that the latter approach is just a special instance of the former, when the Parallel Ray Approximation can be said to hold true.

•Dec 1, 2014•0 citations

ANALYSIS OF LIGHT DIFFRACTION INTERFERENCE PATTERNS IN YOUNG'S DOUBLE SLIT EXPERIMENT

Putri Asnita Gulo

Young's double-slit experiment is a classic and fundamentaldemonstration in physics that strongly supports the wave nature of light throughthe phenomenon of interference. The study aims to deeply analyze the formationof diffraction and interference patterns of light that arise due to the pathdifferences between two coherent light sources. The experiment uses a simple yeteffective setup involving a monochromatic light source, two narrow slits placedclose together, and a screen placed at a certain distance to capture the resultinginterference pattern. Several variables are analyzed in the study, including thewavelength of the light used,the distance between two gaps and the distance fromone gap to anotherThe experimental results confirm the occurrence ofconstructive and destructive interference, resulting in the formation of stripesmoving from bright to dark in the layer. These stripes arise due to the phasedifference between overlapping light waves, and their spacing and clarity areaffected by the physical parameters of the setup. The analysis shows that thespacing between the stripes increases with longer wavelengths and decreases withwider slit spacing. In addition, the cohesion of the light source plays an importantrole in producing a clear and stable interference pattern. This experiment not onlyserves as a concrete verification of the theoretical wave principle in physics, butalso has broader implications in modern optical technologies such as diffractiongratings, holography, and quantum mechanics. This experiment is also relevantfor educational purposes because it provides an experiential learning opportunityfor students to understand the behavior of light and wave interactions. Therefore,this study is expected to be a useful reference in supporting the teaching andlearning of wave optics, especially in demonstrating the dual nature of light andits applications in real-world phenomena.

Journal of Frontier Research in Science and Engineering•Jun 30, 2025•0 citations

Young's Double-Slit Experiment Revisited: Geometric Evidence for Center-to-Center Slit Spacing at 650 nm

Mathias Colin

This paper replicates Young’s double-slit experiment using a 650 nm laser to analyze how light waves interfere. By measuring the resulting fringe patterns, the study reveals that the manufacturer's nominal values actually represent the outer-to-outer edge spacing of the slits rather than the true center-to-center distance.

•Aug 31, 2026•0 citations
We used the focal line of a cylindrical lens illuminated by a collimated expanded He–Ne red laser light as a filamentary light source to observe Young’s interference fringes. When the monochromatic filamentary light source is parallel to Young’s slits, the interference fringes are parallel to them and are well defined and highly contrasted. When the filamentary light source is rotated in a plane parallel to that of the slits, the visibility of the interference fringes is always extremely high, but their geometrical distribution and the distance between them depend on the rotation angle and the observation distance. A simple theoretical model is proposed, based on a cylindrical wave propagated according to the Huygens–Kirchhoff formula. The experimental results coincide remarkably well with the stated theoretical model.
We discuss Young's double-slit experiment using a partially coherent light source consisting of a helium-neon laser incident on a rotating piece of white paper. Such an experiment is appropriate for undergraduate students as an independent project or as part of an advanced lab course. As is well known, the resulting interference pattern is observed to disappear and return, depending on the angular size of the source. Interestingly, while the standard theoretical prediction for the light intensity agrees quite well with experimental data when the fringe visibility is high, the prediction is noticeably off when the visibility is low. A first-principles calculation of the light intensity is performed and shown to agree extremely well with the experimental results for all visibilities.
Is it possible to detect the interference from an extended incoherent source with Young's slits when the source-slits distance is such that all dimensions of the coherence area of the incident light beam are smaller than the distance between the slits? We have experimentally demonstrated that, under the above conditions, interference fringes can be obtained with a controlled degree of visibility by means of coincidence measurements between conujugated beams of the down-conversion luminescence.
In 1801, Thomas Young devised what is now known as the Classical Double Slit Experiment. In this experiment, light waves emanating from two separate sources, interfere to form a pattern of alternating bright and dark fringes on a distant screen. By measuring the position of individual fringe centers, the fringe widths and the variation of average light intensity on the screen, it is possible to compute the wavelength of light itself. The original theoretical analysis of the experiment employs a set of geometric assumptions which are collectively referred to here as the Parallel Ray Approximation. Accordingly, any two rays of light arising from either source and convergent on an arbitrary point on the screen, are considered very nearly parallel to each other in the vicinity of the sources. This approximation holds true only when the screen to source distance is very large and the inter-source distance is much larger than the wavelength of light. The predictions that naturally follow are valid only for fringes located near the center of the screen (e.g. the equal spacing of fringes). But for those fringes located further away from the screen center, the precision of these predictions rapidly wanes. Also when the screen to source distance is comparable to the inter-source separation or when the inter-source distance is comparable to the wavelength of light, the original analysis is no longer applicable. In this paper, the theoretical foundations of Young’s experiment are re-formulated using a newly derived analytical equation of a hyperbola, which forms the locus of the points of intersections of two expanding circular wavefronts (with sources located at the respective centers of expansion). The ensuing predictions of the new analysis are compared with those of the old. And finally, it is shown that the latter approach is just a special instance of the former, when the Parallel Ray Approximation can be said to hold true.
Young's double-slit experiment is a classic and fundamentaldemonstration in physics that strongly supports the wave nature of light throughthe phenomenon of interference. The study aims to deeply analyze the formationof diffraction and interference patterns of light that arise due to the pathdifferences between two coherent light sources. The experiment uses a simple yeteffective setup involving a monochromatic light source, two narrow slits placedclose together, and a screen placed at a certain distance to capture the resultinginterference pattern. Several variables are analyzed in the study, including thewavelength of the light used,the distance between two gaps and the distance fromone gap to anotherThe experimental results confirm the occurrence ofconstructive and destructive interference, resulting in the formation of stripesmoving from bright to dark in the layer. These stripes arise due to the phasedifference between overlapping light waves, and their spacing and clarity areaffected by the physical parameters of the setup. The analysis shows that thespacing between the stripes increases with longer wavelengths and decreases withwider slit spacing. In addition, the cohesion of the light source plays an importantrole in producing a clear and stable interference pattern. This experiment not onlyserves as a concrete verification of the theoretical wave principle in physics, butalso has broader implications in modern optical technologies such as diffractiongratings, holography, and quantum mechanics. This experiment is also relevantfor educational purposes because it provides an experiential learning opportunityfor students to understand the behavior of light and wave interactions. Therefore,this study is expected to be a useful reference in supporting the teaching andlearning of wave optics, especially in demonstrating the dual nature of light andits applications in real-world phenomena.