The compact, cost-effective, and stable setup of in-line digital holographic microscopy (DHM) allows for the production of three-dimensional images, encompassing large fields of view, deep depth of field, and high resolution at the micrometer scale. The theoretical underpinnings and experimental results for an in-line DHM system are detailed, employing a gradient-index (GRIN) rod lens. Furthermore, we create a traditional pinhole-based in-line DHM with diverse configurations to evaluate the resolution and image quality contrast between the GRIN-based and pinhole-based systems. Near a spherical wave source, within a high-magnification regime, our optimized GRIN-based configuration proves superior in resolution, reaching a value of 138 meters. Additionally, holographic imaging of dilute polystyrene microparticles, with diameters of 30 and 20 nanometers, was carried out using this microscope. Through both theoretical calculations and practical experiments, we explored how changes in the distances between the light source and detector, and the sample and detector, affected the resolution. Our findings from both theoretical and experimental approaches align remarkably well.

Artificial optical devices, engineered to mirror the intricate visual system of natural compound eyes, boast an expansive field of view and a remarkable capacity for quickly detecting movement. However, the creation of images within artificial compound eyes is significantly reliant upon a multitude of microlenses. The inherent limitation of a single focal length in the microlens array considerably hinders the practical utility of artificial optical devices, impacting functionalities like distinguishing objects at differing ranges. This study details the fabrication of a curved artificial compound eye, incorporating a microlens array with adjustable focal lengths, using inkjet printing and air-assisted deformation. Modification of the microlens array's spacing resulted in the formation of secondary microlenses situated between the primary microlenses. The respective dimensions of the primary and secondary microlens arrays are 75 meters in diameter and 25 meters in height, and 30 meters in diameter and 9 meters in height. A curved configuration of the planar-distributed microlens array was achieved by means of air-assisted deformation. The reported technique excels in its simplicity and ease of operation, significantly differing from the alternative of modifying the curved base to identify objects at differing distances. The artificial compound eye's field of view is tunable via alterations in the applied air pressure. Objects positioned at differing distances could be distinguished using microlens arrays boasting diverse focal lengths, obviating the requirement for extra components. The varying focal lengths of microlens arrays enable them to discern the small movements of external objects. Implementation of this method could yield a considerable advancement in the optical system's motion perception capabilities. Additionally, the fabricated artificial compound eye's imaging and focusing capabilities were thoroughly tested and assessed. The compound eye, a synthesis of monocular vision and compound eye structure, holds significant promise for the design of sophisticated optical instruments, characterized by extensive field of view and adaptable focusing mechanisms.

We present, by virtue of successfully creating computer-generated holograms (CGHs) via the computer-to-film (CtF) process, a new strategy for rapid and cost-effective hologram manufacturing, to the best of our knowledge. This method facilitates the advancement of CtF processing and manufacturing, all thanks to innovative developments in hologram creation. Utilizing identical CGH calculations and prepress stages, the techniques consist of computer-to-plate, offset printing, and surface engraving. The presented method, synergistically combined with the previously discussed techniques, presents a strong economic advantage and manufacturing feasibility for deployment as security elements.

The global environment is facing a significant threat from microplastic (MP) pollution, which has triggered an acceleration in the development of new methods for identification and characterization. The deployment of digital holography (DH) facilitates the high-throughput detection of micro-particles (MPs) in a flowing sample stream. This article examines the progression of DH-implemented MP screening strategies. The hardware and software facets of the problem are comprehensively examined by us. Adavosertib concentration In automatic analysis reports, the function of artificial intelligence, powered by smart DH processing, is prominently displayed for its applications in classification and regression tasks. The framework further examines the sustained development and accessibility of field-portable holographic flow cytometers for water quality studies in recent years.

The meticulous measurement of the dimensions of each section of the mantis shrimp's body is paramount to accurately quantify its design and select the ideal ideotype. Recently, point clouds have emerged as an effective and efficient solution. Still, the presently used manual measurement process is associated with considerable labor input, high costs, and high uncertainty. To accurately measure the phenotypes of mantis shrimps, automatic segmentation of organ point clouds is a crucial initial step and a prerequisite. However, there is a paucity of research dedicated to the task of segmenting point clouds of mantis shrimp. This research presents a framework for the automated segmentation of mantis shrimp organs from multiview stereo (MVS) point clouds, thereby filling this gap. A Transformer-based multi-view stereo (MVS) architecture is initially employed to derive a dense point cloud from a collection of calibrated mobile phone images and calculated camera parameters. For mantis shrimp organ segmentation, an enhanced point cloud segmentation technique, ShrimpSeg, is developed. It utilizes both local and global features in light of contextual information. Adavosertib concentration The evaluation results demonstrate that the per-class intersection over union for organ-level segmentation is 824%. Comprehensive trials showcase ShrimpSeg's effectiveness, placing it above competing segmentation approaches. This work may be beneficial for the refinement of shrimp phenotyping and intelligent aquaculture technologies at the level of production-ready shrimp.

In the realm of high-quality spatial and spectral mode shaping, volume holographic elements stand out. Many applications in microscopy and laser-tissue interaction rely on the precise placement of optical energy at specific locations, with minimal effects on the surrounding tissues. Due to the substantial energy disparity between the input and focal plane, abrupt autofocusing (AAF) beams are a potential solution for laser-tissue interaction. The recording and reconstruction of a volume holographic optical beam shaper, made from PQPMMA photopolymer, is presented here for shaping an AAF beam. The generated AAF beams are characterized experimentally, displaying a broadband operational characteristic. In the fabricated volume holographic beam shaper, optical quality and long-term stability are exceptionally maintained. Our method excels in multiple areas, including precise angular selectivity across a broad spectrum, and an inherently compact physical design. Applications of this method extend to the design of compact optical beam shapers for biomedical laser systems, microscopy illumination, optical tweezers, and experiments on laser-tissue interactions.

Despite the escalating interest in computer-generated holograms, deriving their associated depth maps continues to be an unsolved hurdle. Our proposed investigation in this paper delves into the application of depth-from-focus (DFF) methods, aiming to retrieve depth information from the hologram. We delve into the various hyperparameters essential for employing this method, examining their influence on the ultimate outcome. The outcome of the DFF methods applied to hologram data for depth estimation demonstrates the importance of carefully chosen hyperparameters.

A 27-meter fog tube, filled with ultrasonically created fog, is used in this paper to demonstrate digital holographic imaging. Holography's potent imaging capabilities through scattering media are a direct result of its high sensitivity. We utilize large-scale experiments to investigate the applicability of holographic imaging within road traffic, a vital aspect for autonomous vehicles' need for reliable environmental awareness under all weather conditions. The illumination power requirements for single-shot off-axis digital holography are contrasted with those of conventional coherent imaging methods, showcasing a 30-fold reduction in illumination power needed for identical imaging distances with holographic imaging. A simulation model and quantitative descriptions of how various physical parameters impact the imaging range are integral to our work, alongside signal-to-noise ratio considerations.

Optical vortex beams exhibiting fractional topological charge (TC) have attracted significant attention due to their distinctive transverse intensity distribution and fractional phase front. Potential applications of this technology span micro-particle manipulation, optical communication, quantum information processing, optical encryption, and optical imaging. Adavosertib concentration The applications described require detailed knowledge of the orbital angular momentum, which is directly correlated to the fractional TC characteristic of the beam. Thus, the precise and accurate assessment of fractional TC warrants attention. Employing a spiral interferometer and fork-shaped interference patterns, this study presents a simple method for determining the fractional topological charge (TC) of an optical vortex with a resolution of 0.005. The results obtained with the proposed technique are satisfactory in the presence of low to moderate atmospheric turbulence, having direct implications for free-space optical communication applications.

To maintain road safety for vehicles, the detection of tire defects plays a vital and indispensable role. Consequently, a swift, non-invasive method is necessary for the frequent testing of tires in use, as well as for the quality assessment of newly manufactured tires within the automotive sector.