0000000000107965
AUTHOR
Manuel Martínez Corral
Practical guide for setting up a Fourier light-field microscope, Appl. Opt. 62, 4228 (2023)
Apractical guide for the easy implementation of a Fourier light-field microscope is reported. The Fourier light-field concept applied to microscopy allows the capture in real time of a series of 2D orthographic images of microscopic thick dynamic samples. Such perspective images contain spatial and angular information of the light-field emitted by the sample.Afeature of this technology is the tight requirement of a double optical conjugation relationship, and also the requirement of NA matching. For these reasons, the Fourier light-field microscope being a non-complex optical system, a clear protocol on howto set up the optical elements accurately is needed. In this sense, this guide is aim…
Long working range light field microscope with fast scanning multifocal liquid crystal microlens array
The light field microscope has the potential of recording the 3D information of biological specimens in real time with a conventional light source. To further extend the depth of field to broaden its applications, in this paper, we proposed a multifocal high-resistance liquid crystal microlens array instead of the fixed microlens array. The developed multifocal liquid crystal microlens array can provide high quality point spread function in multiple focal lengths. By adjusting the focal length of the liquid crystal microlens array sequentially, the total working range of the light field microscope can be much extended. Furthermore, in our proposed system, the intermediate image was placed i…
Off-axis Digital Holographic Microscopy: practical design parameters for operating at diffraction limit
The utilization of microscope objectives (MOs) in digital holographic microscopy (DHM) has associated effects that are not present in conventional optical microscopy. The remaining phase curvature, which can ruin the quantitative phase imaging, is the most evident and analyzed. As phase imaging is considered, this interest has made possible the development of different methods of overcoming its undesired consequences. Additionally to the effects in phase imaging, there exist a set of less obvious conditions that have to be accounted for as MOs are utilized in DHM to achieve diffraction-limit operation. These conditions have to be considered even in the case in which only amplitude or intens…
Full parallax 3D display from Kinect v1 and v2
We exploit the two different versions of Kinect, v1 and v2, for the calculation of microimages projected onto integral-imaging displays. Our approach is based on composing a three-dimensional (3-D) point cloud from a captured depth map and RGB information. These fused 3-D maps permit to generate an integral image after projecting the information through a virtual pinhole array. In our analysis, we take into account that each of the Kinect devices has its own inherent capacities and individualities. We illustrate our analysis with some imaging experiments, provide the distinctive differences between the two Kinect devices, and finally conclude that Kinect v2 allows the display of 3-D images …
Multidimensional Integral Imaging for Sensing, Visualization, and Recognition in Degraded Environments
An overview of multidimensional integral imaging for sensing, visualization, and recognition in degraded environments is presented. Applications include 3D visualization, photon starved imaging, material inspection, IR imaging, passive depth estimation, automated human gesture recognition, and long-range imaging.
Three-Dimensional Imaging and Display through Integral Photography
Here, we present a review of the proposals and advances in the field of three-dimensional (3D) imaging acquisition and display made in the last century. The most popular techniques are based on the concept of stereoscopy. However, stereoscopy does not provide real 3D experience, and produces discomfort due to the conflict between convergence and accommodation. For this reason, we focus this paper on integral imaging, which is a technique that permits the codification of 3D information in an array of 2D images obtained from different perspectives. When this array of elemental images is placed in front of an array of microlenses, the perspectives are integrated producing 3D images with full p…
Multidimensional Integral Imaging and Recognition in Degraded Environments
We present an overview of our work on multidimensional integral imaging systems. Integral-imaging-based multidimensional optical sensing and imaging will be described for 3-D visualization, seeing through obscurations, material inspection, augmented reality, biomedical applications, and object recognition from microscales to long-range imaging.
Enhancing spatial resolution in digital holographic microscopy by biprism structured illumination
In a recent Letter by Seo et al. [Opt. Lett. 37, 4976 (2012)], the numerical correction of the quadratic phase distortion introduced by the microscope objective in digital holographic microscopy (DHM) has been presented. In this comment, we would like to draw to the attention of the authors and the readers in general that this approach could not be the optimal solution for maintaining the accuracy of the quantitative phase via DHM. We recall that the use of telecentric imaging systems in DHM simplifies the numerical processing of the phase images and produces more accurate measurements.
Diabetes screening by telecentric digital holographic microscopy
Diabetes is currently the world's fastest growing chronic disease and it is caused by deficient production of insulin by the endocrine pancreas or by abnormal insulin action in peripheral tissues. This results in persistent hyperglycaemia that over time may produce chronic diabetic complications. Determination of glycated haemoglobin level is currently the gold standard method to evaluate and control sustained hyperglycaemia in diabetic people. This measurement is currently made by high-performance liquid chromatography, which is a complex chemical process that requires the extraction of blood from the antecubital vein. To reduce the complexity of that measurement, we propose a fully-optica…
Three Dimensional Sensing, Visualization, and Display
This keynote address will present an overview of recent advances in Three-dimensional (3D) sensing, imaging and display. We shall discuss both passive sensing integral imaging and active sensing computational holographic imaging for 3D visualization, display, and image recognition. Mathematical analysis, computer simulations, and optical experimental results will be presented. There are numerous applications of these technologies including medical 3D imaging, 3D visualization, 3D identification and inspection, 3D television, 3D video, 3D multimedia, interactive communication, education, entertainment, and commerce.