Search results for "Depth of field"
showing 10 items of 33 documents
Progress in 3-D Multiperspective Display by Integral Imaging
2009
Three-dimensional (3-D) imaging techniques have the potential to establish a future mass-market in the fields of entertainment and communications. Integral imaging (InI), which can capture and display true 3-D color images, has been seen as the right technology for 3-D viewing for audiences of more than one person. Due to the advanced degree of its development, InI technology could be ready for massive commercialization in the coming years. This development is the result of a strong research effort performed over the past few years. In this sense, this paper is devoted to reviewing some recent advances in InI, which have allowed improvement in the response of InI systems to the problems of …
Recent Advances in the Capture and Display of Macroscopic and Microscopic 3-D Scenes by Integral Imaging
2017
The capture and display of images of 3-D scenes under incoherent and polychromatic illumination is currently a hot topic of research, due to its broad applications in bioimaging, industrial procedures, military and surveillance, and even in the entertainment industry. In this context, Integral Imaging (InI) is a very competitive technology due to its capacity for recording with a single exposure the spatial-angular information of light-rays emitted by the 3-D scene. From this information, it is possible to calculate and display a collection of horizontal and vertical perspectives with high depth of field. It is also possible to calculate the irradiance of the original scene at different dep…
3D Integral Microscopy based in far-field detection
2018
Lately, Integral-Imaging systems have shown very promising capabilities of capturing the 3D structure of micro- scopic and macroscopic scenes. The aim of this work is to provide an optimal design for 3D-integral microscopy with extended depth of field and enhanced lateral resolution. By placing an array of microlenses at the aperture stop of the objective, this setup provides a set of orthographic views of the 3D sample. Adopting well known integral imaging reconstruction algorithms it can be shown that the depth of field as well as spatial resolution are improved with respect to conventional integral microscopy imaging. Our claims are supported on theoretical basis and experimental images …
Optical implementation of micro-zoom arrays for parallel focusing in integral imaging.
2010
We report 3D integral imaging with an electronically tunable-focal-length lens for improved depth of field. The micro-zoom arrays are generated and implemented based on the concept of parallel apodization. To the best of our knowledge, this is the first report of parallel dynamic focusing in integral imaging based on the use of micro-zoom arrays.
Three-dimensional imaging system with both improved lateral resolution and depth of field considering non-uniform system parameters
2018
In this paper, we propose a new 3D passive image sensing and visualization technique to improve lateral resolution and depth of field (DoF) of integral imaging simultaneously. There is a resolution trade-off between lateral resolution and DoF in integral imaging. To overcome this issue, a large aperture and a small aperture can be used to record the elemental images to reduce the diffraction effect and extend the DoF, respectively. Therefore, in this paper, we utilize these two pickup concepts with a non-uniform camera array. To show the feasibility of our proposed method, we implement an optical experiment. For comparison in details, we calculate the peak signal-to-noise ratio (PSNR) as th…
3D integral imaging with optical processing
2008
Integral imaging (InI) systems are imaging devices that provide auto-stereoscopic images of 3D intensity objects. Since the birth of this new technology, InI systems have faced satisfactorily many of their initial drawbacks. Basically, two kind of procedures have been used: digital and optical procedures. The "3D Imaging and Display Group" at the University of Valencia, with the essential collaboration of Prof. Javidi, has centered its efforts in the 3D InI with optical processing. Among other achievements, our Group has proposed the annular amplitude modulation for enlargement of the depth of field, dynamic focusing for reduction of the facet-braiding effect, or the TRES and MATRES devices…
Bio-imaging with the helium-ion microscope: A review
2021
Scanning helium-ion microscopy (HIM) is an imaging technique with sub-nanometre resolution and is a powerful tool to resolve some of the tiniest structures in biology. In many aspects, the HIM resembles a field-emission scanning electron microscope (FE-SEM), but the use of helium ions rather than electrons provides several advantages, including higher surface sensitivity, larger depth of field, and a straightforward charge-compensating electron flood gun, which enables imaging of non-conductive samples, rendering HIM a promising high-resolution imaging technique for biological samples. Starting with studies focused on medical research, the last decade has seen some particularly spectacular …
FIMic: design for ultimate 3D-integral microscopy of in-vivo biological samples
2018
In this work, Fourier integral microscope (FIMic), an ultimate design of 3D-integral microscopy, is presented. By placing a multiplexing microlens array at the aperture stop of the microscope objective of the host microscope, FIMic shows extended depth of field and enhanced lateral resolution in comparison with regular integral microscopy. As FIMic directly produces a set of orthographic views of the 3D-micrometer-sized sample, it is suitable for real-time imaging. Following regular integral-imaging reconstruction algorithms, a 2.75-fold enhanced depth of field and [Formula: see text]-time better spatial resolution in comparison with conventional integral microscopy is reported. Our claims …
Fractal photon sieve
2006
A novel focusing structure with fractal properties is presented. It is a photon sieve in which the pinholes are appropriately distributed over the zones of a fractal zone plate. The focusing properties of the fractal photon sieve are analyzed. The good performance of our proposal is demonstrated experimentally with a series of images obtained under white light illumination. It is shown that compared with a conventional photon sieve, the fractal photon sieve exhibits an extended depth of field and a reduced chromatic aberration.
Large Depth-of-Field Integral Microscopy by Use of a Liquid Lens
2018
Integral microscopy is a 3D imaging technique that permits the recording of spatial and angular information of microscopic samples. From this information it is possible to calculate a collection of orthographic views with full parallax and to refocus computationally, at will, through the 3D specimen. An important drawback of integral microscopy, especially when dealing with thick samples, is the limited depth of field (DOF) of the perspective views. This imposes a significant limitation on the depth range of computationally refocused images. To overcome this problem, we propose here a new method that is based on the insertion, at the pupil plane of the microscope objective, of an electrical…