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This paper proposes a non-computational method of counteracting the effect of image degradation introduced by the diffraction phenomenon in lensless microscopy. All the optical images (whether focused by lenses or not) are diffraction…

Optics · Physics 2021-04-08 Sanjeev Kumar , Manjunatha Mahadevappa , Pranab Kumar Dutta

A smartphone camera can be used for measuring the width and distance of an object by taking its photograph. The focal length of the camera lens can be determined very accurately by finding the image width of an object on the camera sensor…

Physics Education · Physics 2021-11-15 Sanjoy Kumar Pal , Soumen sarkar , Surajit Chakrabarti

Compressive spectral imaging enables to reconstruct the entire three-dimensional (3D) spectral cube from a few multiplexed images. Here, we develop a novel compressive spectral imaging technique using diffractive lenses. Our technique uses…

Image and Video Processing · Electrical Eng. & Systems 2019-09-24 Oğuzhan Fatih Kar , Figen S. Oktem

Multispectral imaging has been used for numerous applications in e.g., environmental monitoring, aerospace, defense, and biomedicine. Here, we present a diffractive optical network-based multispectral imaging system trained using deep…

Optics · Physics 2023-04-07 Deniz Mengu , Anika Tabassum , Mona Jarrahi , Aydogan Ozcan

We propose an efficient inverse design approach for multifunctional optical elements based on adaptive deep diffractive neural networks (a-D$^2$NNs). Specifically, we introduce a-D$^2$NNs and design two-layer diffractive devices that can…

Optics · Physics 2022-06-08 Yuyao Chen , Yilin Zhu , Wesley A. Britton , Luca Dal Negro

Diffractive optical elements that divide an input beam into a set of replicas are used in many optical applications ranging from image processing to communications. Their design requires time-consuming optimization processes, which, for a…

Digital holography numerically restores three-dimensional image information using optically captured diffractive waves. The required bandwidth is larger than that of hologram pixel at a closer distance in the Fresnel diffraction regime,…

Optics · Physics 2024-01-12 Byung Gyu Chae

In this paper we show how students can measure optical features of smartphone displays through three experiments. Observing diffraction patterns from smartphone displays allows students to determine the Pixels Per Inch (PPI). Observing…

Physics Education · Physics 2025-11-26 Mamatha Ramanjineyulu Maddur , Hemansh Shah , Praveen Pathak

Strong intensity attenuation limits the use of conventional diffraction-free optical elements. We show a possible solution to the exponential intensity attenuation limiting the use of Fresnel-type diffraction-free nanometer-scale optics by…

Optics · Physics 2013-01-17 M. I. Mechler , Z. Tibai , S. V. Kukhlevsky

We propose an optical encryption framework that can encrypt and decrypt large-sized images beyond the size of the encrypted image using our two methods: random phase-free method and scaled diffraction. In order to record the entire image…

Novel optical elements containing semitransparent wavelike films embedded into the bulk of transparent material, which form a reflection image without transmitted light distortion, are studied. The dynamic theory of light diffraction by a…

Optics · Physics 2018-05-23 Anatoly M. Smolovich , Valery Chernov

Thin-film optical filters can nowadays be integrated onto pixels of commercial image sensors used for spectral imaging. A drawback of having more filters on an image sensor is a loss in spatial resolution which could be regained by using…

Optics · Physics 2021-06-03 Thomas Goossens

This study reports the successful fabrication of high-positive refractive index change waveguides, exceeding 0.02 in fluoride glasses, marking a significant advancement in integrated optical components for visible to mid-infrared…

Coherent diffractive imaging is a technique that recovers the sample image by numerically inverting its diffraction pattern. We propose a generalization of this method for the inversion of multi-wavelength data. Using this approach, we show…

Optics · Physics 2020-05-08 Erik Malm , Edwin Fohtung , Anders Mikkelsen

A broad range of imaging and sensing technologies in the infrared require large Field-of-View (FoV) operation. To achieve this, traditional refractive systems often employ multiple elements to compensate for aberrations, which leads to…

Reflective imaging systems form an important part of photonic devices such as spectrometers, telescopes, augmented and virtual reality headsets or lithography platforms. Reflective optics provide unparalleled spectral performance and can be…

The values of the signal-to-noise ratio are determined, at which the method of processing X-ray diffraction data reveals reflections with intensity less than the noise component of the background. The possibilities of the method are…

We establish simple quantitative criterium for the search of new dielectric materials with high values of the refractive index in the visible range. It is demonstrated, that for light frequencies below the band gap the latter is determined…

Mesoscale and Nanoscale Physics · Physics 2020-07-24 Roman Polozkov , Anton Shubnik , Ivan Shelykh , Ivan Iorsh

We present a novel differential refractive index sensor based on arrays of photonic molecules (PM) of dielectric cylinders and two structural defect cavities. The transmission spectrum of the photonic proposed structure as sensor shows a…

Optics · Physics 2016-08-09 Angel Andueza , Jesus Perez-Conde , Joaquin Sevilla

We have theoretically proposed a highly compact refractive-index sensor consisted of edge-cavity and line-defect waveguide in two-dimensional photonic crystal. The sensing object is completely outside of the single enclosed surface of the…

Optics · Physics 2023-09-22 Ma Luo , Kaichan Zhong , Jieli Luo