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Computer-generated hologram (CGH) is an evolving field that facilitates three-dimensional displays, with speckle noise reduction being a pivotal challenge. In hologram synthesis, complex data with random phase distributions are typically employed as carrier waves for wide viewing angles and a shallow depth of focus (DOF). However, these carrier waves are a source of speckle noise, which can significantly degrade image quality. In this paper, we propose a novel technique for speckle reduction for single sideband (SSB)-encoded holograms, applicable to any arbitrary 3D object. The proposed method focuses on optimizing the random carrier wave used in the hologram synthesis to achieve a uniform amplitude distribution at the object's location. This optimization results in a carrier wave that consistently exhibits uniform amplitude at specific depth planes, leading to a significant reduction of the speckle occurring from the carrier wave. The proposed method has been validated through simulations and optical experiments.

Background: Glioblastoma (GBM) is the most common and lethal primary brain tumor in adults, with limited treatment modalities and poor prognosis. Recent studies have highlighted the importance of considering sex differences in cancer incidence, prognosis, molecular disparities, and treatment outcomes across various tumor types, including colorectal adenocarcinoma, lung adenocarcinoma, and GBM., Methods: We performed comprehensive analyses of large-scale multi-omics data (genomic, transcriptomic, and proteomic data) from TCGA, GLASS, and CPTAC to investigate the genetic and molecular determinants that contribute to the unique clinical properties of male and female GBM patients., Results: Our results revealed several key differences, including enrichments of MGMT promoter methylation, which correlated with increased overall and post-recurrence survival and improved response to chemotherapy in female patients. Moreover, female GBM exhibited a higher degree of genomic instability, including aneuploidy and tumor mutational burden. Integrative proteomic and phosphor-proteomic characterization uncovered sex-specific protein abundance and phosphorylation activities, including EGFR activation in males and SPP1 hyperphosphorylation in female patients. Lastly, the identified sex-specific biomarkers demonstrated prognostic significance, suggesting their potential as therapeutic targets., Conclusions: Collectively, our study provides unprecedented insights into the fundamental modulators of tumor progression and clinical outcomes between male and female GBM patients and facilitates sex-specific treatment interventions. Highlights Female GBM patients were characterized by increased MGMT promoter methylation and favorable clinical outcomes compared to male patients. Female GBMs exhibited higher levels of genomic instability, including aneuploidy and TMB. Each sex-specific GBM is characterized by unique pathway dysregulations and molecular subtypes. EGFR activation is prevalent in male patients, while female patients are marked by SPP1 hyperphosphorylation., (© 2024. The Author(s).)

The evolutionary trajectory of glioblastoma (GBM) is a multifaceted biological process that extends beyond genetic alterations alone. Here, we perform an integrative proteogenomic analysis of 123 longitudinal glioblastoma pairs and identify a highly proliferative cellular state at diagnosis and replacement by activation of neuronal transition and synaptogenic pathways in recurrent tumors. Proteomic and phosphoproteomic analyses reveal that the molecular transition to neuronal state at recurrence is marked by post-translational activation of the wingless-related integration site (WNT)/ planar cell polarity (PCP) signaling pathway and BRAF protein kinase. Consistently, multi-omic analysis of patient-derived xenograft (PDX) models mirror similar patterns of evolutionary trajectory. Inhibition of B-raf proto-oncogene (BRAF) kinase impairs both neuronal transition and migration capability of recurrent tumor cells, phenotypic hallmarks of post-therapy progression. Combinatorial treatment of temozolomide (TMZ) with BRAF inhibitor, vemurafenib, significantly extends the survival of PDX models. This study provides comprehensive insights into the biological mechanisms of glioblastoma evolution and treatment resistance, highlighting promising therapeutic strategies for clinical intervention., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: One in eight patients is affected by a mental health condition, and interprofessional mental health teams collaborate to improve patient care. While pharmacists and social workers are recognized as mental health team members, there is a lack of literature describing interprofessional relations and education between these professions, especially as it pertains to mental health. The purpose of this review was to identify and characterize reports describing pharmacist-social worker interprofessional relations and education within mental health., Methodology: To address this knowledge gap, this scoping review was conducted to collect and characterize reports published between January 1, 1960 and August 18, 2023 describing pharmacist-social worker interprofessional relations and education within the field of mental health. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines were followed. Ovid MEDLINE, CINAHL, and Social Work Abstracts were searched using keywords "pharmacy student," "pharmacist," "social work student," "social worker," and "social work." Reports were included if they were published in English and interprofessional relations or education occurred directly between (student) pharmacists and social workers., Results: Three hundred twenty records were identified and three records were included: one cross sectional study, one qualitative educational project, and one case report. Each record suggested positive patient and/or educational outcomes developing from pharmacist-social worker interprofessional relations and education. In clinical practice, pharmacist-social work teams identified mental health risk factors, reduced 30-day readmissions, and improved post-discharge telehealth care. In the classroom, a social worker improved pharmacy students' confidence assessing patient suicidal ideations., Conclusions: This scoping review identified needs and areas for future research: pharmacist interprofessional education with Master of Social Work and Doctor of Social Work degree students, transitional care and mental health outcome measure reporting using evidence-based outcomes, and development of scholarly teaching projects utilizing higher-level educational frameworks beyond learner reactions., Competing Interests: Jamie Knisley is employed by Total Dose (Edmond, OK) as a post-graduate year 1 community pharmacy resident. The remaining authors declare that they have no competing interests., (© 2024 Boylan et al.)

As the community food environment is known to be an important factor in healthy food choices, it needs to be measured, to increase awareness and improve healthy eating. The objective of this study was to develop a perceived community food accessibility measurement (P-CFAM) questionnaire applicable to older adults in Korea and evaluate its reliability and validity. The questionnaire was developed based on community food environment factors that were found to affect food choices in previous studies. We evaluated the internal consistency reliability, construct validity, and criterion-related validity. The subjects were 188 older adults for validity. The Cronbach's alpha value for the reliability measure was 0.9. The confirmatory factor analysis to evaluate the construct validity of the questionnaire showed values close to those of the optimal model (GFI = 0.983, AGFI = 0.948, RMR = 0.004, NFI = 0.987, CFI = 0.996). Regarding the criterion-related validity, the P-CFAM questionnaire results were significantly related to objective measurement indicators such as the number of grocery stores, the travel time to a grocery store, and the intake of vegetables and fruit. In conclusion, the developed P-CFAM questionnaire was shown to be reliable and valid, and useful for assessing older adults' perceptions of community food accessibility in Korea.

We analyze an image quality of a holographic lens (HL) in order to implement compact near-eye displays using a flat-panel-type micro-display panel. The proposed method utilizes a non-converging signal wave in a fabrication process of the HL, so that it provides affordable eye-box size with minimizing the aberration due to rays in the off-Bragg condition. For analyzing and optimizing the HL based on the non-converging signal wave, we introduce a comprehensive analysis model for an assessment of the image quality in the HL. The analysis model, inspired from the conventional lens design strategy for near-eye displays, evaluates the focal spot quality for incident rays forming each pixel with considering the on- and off-Bragg diffraction. The theoretical analysis is validated by simulation results using a volume hologram model in Zemax OpticStudio. As experimental verifications, we realize a prototype system using photopolymer-based HLs in a green color with the high transmittance of 89.3%. The image quality of the HLs is analyzed, which coincides well with the proposed analysis and assessment metric. By building a compact experimental setup employing the HL and a micro-organic light emitting diode display, we present see-through images with 8.0 mm of eye-box with reduced aberrations.

In this study, we have examined the anticancer effects of SH005S7 on MET-amplified and (HCC827GR) NSCLC cells and their primary HCC827 cells. In vitro , first of all, cell viability and colony formation assay confirmed the growth inhibitory effects of SH005S7 on both cells. Second, SH005S7 inactivated EGFR-related multiple cell signaling, which was associated with a marked decrease in the constitutive phosphorylation of EGFR, HER3, MET, AKT, and ERK. Third, SH005S7 attenuated the anchorage-independent cell growth. Fourth, SH005S7 blocked invasive and metastatic capability by downregulation of mesenchymal markers-vimentin, snail, and MMP-9. Fifth, BrdU assay confirmed the cell cycle arrest of SH005S7 on these cells. When administered orally to nude mice xenografically transplanted human NSCLC, SH005S7 inhibited the growth of tumor and did not cause hepatotoxicity and nephrotoxicity in animals. Immunohistochemical and Western blot analyses of tissue showed that the suppression of growth correlated with inhibition of proliferation (Ki-67, PCNA), invasiveness (vimentin, snail), and angiogenesis (CD31) marker and decrement in the constitutive and phosphorylation of EGFR, HER3, MET, AKT, and ERK. Additionally, SH005S7 had immune stimulatory effects by TNF- α cytokine release on macrophage, without cell cytotoxicity. Overall, our results suggest that SH005S7 can inhibit the growth of MET-amplified and gefitinib-resistant NSCLC cells through the suppression of EGFR-related multiple targets linked to overcome gefitinib resistance., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2022 Sooyeon Kang et al.)

We propose a projection-type see-through near-to-eye display by combining two holographic optical elements (HOEs), a holographic lens with the on-axis projection configuration and a holographic diffuser. The proposed method provides an enlarged eye-box by virtue of diffusing properties of an HOE diffuser (HOED) without any temporal multiplexing methods. In this paper, a thorough analysis on imaging characteristics of an HOE lens (HOEL) according to the projection configuration is provided, so that we optimize the recording geometry of the HOEL with the passively enlarged eye-box. The theoretical analysis is validated by simulation results using a volume hologram model in OpticStudio. As experimental verifications, we realize a prototype of the proposed method using the photopolymer-based HOEs in a single color. The fabricated HOEL and HOED show high transmittance of 84.9% and 62.2%, respectively. By using the fabricated HOED with a diffusing angle over 20 ° and an angular selectivity of 8.7 °, the prototype successfully provides see-through images with the eye-box larger than 5 mm in width.

Controlling of biofilms formation in numerous pathogenic bacteria is one of the most difficult tasks in the control of bacterial diseases. Plasma has attracted extensive attention due to their potential applications for effective inhibiting of biofilm. Recently, plasma-activated water (PAW) has developed as an alternative method for bacterial inactivation and disinfection of foods owing to advantages of more convenient and efficient storage and transportation than direct plasma application. However, most previous studies about PAW have only focused on the improvement of its antibacterial effect instead of antibiofilm activity. Therefore, we report the development of N 2 plasma treated buffer (NPB) and the super-antibiofilm effect of NPB against Pseudomonas syringae pv. tomato DC3000 ( Pst DC3000) as a plant pathogenic bacterium. Scavenger assays using various antioxidants revealed that reactive oxygen species were involved in the inhibitory cellular actions of NPB, with H 2 O 2 and singlet oxygen proving essential for bacterial death. Intensive analysis of NPB, stored at different periods and temperatures, showed that the antimicrobial efficacy was well maintained for 3 months at - 80 °C. Importantly, further studies showed that NPB effectively inhibited not only the growth of planktonic Pst DC3000 but also biofilm formation. The remarkable inhibition on the biofilm was analyzed and visualized using LIVE/DEAD viability assays and confocal laser scanning microscopy (CLSM) imaging. The 3D CLSM imaging data revealed that the bactericidal activity of NPB was permeable enough to affect the cells embedded inside the biofilm. This prominent permeability could be a crucial feature of NPB contributing to effective super-antibiofilm., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s). 2019.)

This paper proposes a Gaussian process-based method for trajectory learning and generation of individualized gait motions at arbitrary user-designated walking speeds, intended to be used in generating reference motions for robotic gait rehabilitation systems. We utilize a nonlinear dimension reduction technique based on Gaussian process dynamical models (GPDMs), in which the internal dynamics is modeled as a second-order Markov process evolving in a lower-dimensional latent space. After the GPDM parameters are identified with training data obtained from gait motions of healthy subjects walking at different speeds, our method then employs Gaussian process regression (GPR) to predict the initial two states of the latent space dynamics from any arbitrary desired walking speed and the anthropometric parameters of the test subject. Motions are then generated by directly mapping the latent space dynamics to joint trajectories. Experimental studies involving more than 100 subjects indicate that our method generates gait patterns with 30% less mean square prediction errors compared to recent state-of-the-art methods, while also allowing for arbitrary user-specified walking speeds.

Staphylococcus aureus is an important pathogen implicated in various diseases, including staphylococcal food poisoning. Bacteriocins are considered safe and effective antimicrobial substances for the prevention of the growth of pathogenic bacteria. In this article, we describe the purification and characterization of pasteuricin, a novel bacteriocin produced by Staphylococcus pasteuri RSP-1. A cell-free supernatant of S. pasteuri RSP-1 exerted strong antimicrobial activity against staphylococci, including methicillin-resistant S. aureus (MRSA), and gram-positive bacteria. The loss of antimicrobial activity upon treatment with proteolytic enzymes confirmed the proteinaceous nature of pasteuricin. A rapid and pronounced bactericidal effect of pasteuricin was confirmed by a live-dead bacterial viability assay. To our knowledge, pasteuricin is the first reported S. pasteuri bacteriocin that inhibits S. aureus. Because pasteuricin is characterized by strong antimicrobial activity and high stability, it has potential as an alternative antimicrobial agent to antibiotics.

Despite the unique advantages of nanochannels imparted by their small size, their utility is limited by the lack of affordable and versatile fabrication methods. Moreover, nanochannel-incorporated fluidic devices require micro-sized conduit integration for efficient access of liquid samples. In this study, a simple and cost-effective fabrication method for mixed-scale channel networks via hot-embossing of poly(methyl methacrylate) (PMMA) using a carbon stamp is demonstrated. Due to its high rigidity, PMMA ensures collapse-free channel fabrication. The carbon stamp is fabricated using only batch microfabrication and has a convex architecture that allows the fabrication of a complex channel network via a single imprinting process. In addition, the microchannels are connected to nanochannels via three-dimensional (3D) microfunnels that serve as single-particle-entrapment chambers, ensuring smooth transport of samples into the nanochannels. Owing to the 3D geometry of the microfunnels and the small size of the nanochannels, a solute gradient can be generated locally at the microfunnel. This local solute gradient enables the entrapment of microparticles at the microfunnels via diffusiophoresis, which can manipulate the particle motion in a controllable manner, without any external equipment or additional electrode integration into the channels. To the best of our knowledge, this is the first report of diffusiophoresis-based single-particle entrapment.

This paper presents a handheld device that is capable of simplifying multistep assays to perform sensitive detection of foodborne pathogens. The device is capable of multiplexed detection of Escherichia coli (E. coli) O157:H7, Salmonella Typhimurium (S. Typhimurium), Staphylococcus aureus, and Bacillus cereus. The limit of detection for each bacterium was characterized, and then, the detection of bacteria from contaminated fresh lettuces was demonstrated for two representative foodborne pathogens. We employed a sample pretreatment protocol to recover and concentrate target bacteria from contaminated lettuces, which can detect 1.87 × 10 4 CFU of E. coli O157:H7 and 1.47 × 10 4 CFU of S. Typhimurium/1 g of lettuce without an enrichment process. Lastly, we demonstrated that the limit of detection can be reduced to 1 CFU of E. coli O157:H7 and 1 CFU of S. Typhimurium/1 g of lettuce by including a 6 h enrichment of contaminated lettuces in growth media before pretreatment.

Coagulase-negative staphylococci (CNS) are opportunistic pathogens that are currently emerging as causative agents of human disease. Though CNS are widespread in the clinic and food, their precise identification at species level is important. Here, using 16S rRNA sequencing, 55 staphylococcal isolates were identified as S. capitis, S. caprae, S. epidermidis, S. haemolyticus, S. pasteuri, S. saprophyticus, S. warneri, and S. xylosus. Although 16S rRNA sequencing is universally accepted as a standard for bacterial identification, the method did not effectively discriminate closely related species, and additional DNA sequencing was required. The divergence of the sodA gene sequence is higher than that of 16S rRNA. To devise a rapid and accurate identification method, sodA-specific primers were designed to demonstrate that species-specific multiplex polymerase chain reaction (PCR) can be used for the identification of CNS species. The accuracy of this method was higher than that of phenotypic identification; the method is simple and less time-consuming than 16S rRNA sequencing. Of the 55 CNS isolates, 92.72% were resistant to at least one antibiotic, and 60% were resistant to three or more antibiotics. CNS isolates produced diverse virulence-associated enzymes, including hemolysin (produced by 69.09% of the isolates), protease (65.45%), lipase (54.54%), lecithinase (36.36%), and DNase (29.09%); all isolates could form a biofilm. Because of the increasing pathogenic significance of CNS, the efficient multiplex PCR detection method developed in this study may contribute to studies for human health.

Carocin D is a bacteriocin produced by Pectobacterium carotovorum subsp. carotovorum Pcc21. Carocin D inhibits the growth of P carotovorum subsp. carotovorum and closely related strains. Pectobacterium carotovorum subsp. carotovorum is a causative bacterium for soft rot disease and leads to severe economic losses. Bacteriocins recognize and interact with a specific membrane protein of target bacteria as a receptor. To identify the receptor responsible for carocin D recognition, mutants that underwent a phenotypic change from carocin D sensitivity to carocin D insensitivity were screened. Based on Tn5 insertions, carocin D sensitivity was dependent on expression of the outer membrane protein OmpF. The insensitivity of the mutant (Pcc3MR) to carocin D was complemented with ompF from carocin D-sensitive strains, not from carocin D-resistant strains. The selectivity between sensitive and resistant strains could be attributed to variation in OmpFs in the cell-surface-exposed regions. Based on sequence analysis and complementation assays, it appears that carocin D uses OmpF as a receptor and is translocated by the TonB system. According to previously reported translocation mechanisms of colicins, OmpF works along with the TolA system rather than the TonB system. Therefore, the current findings suggest that carocin D is imported by a unique colicin-like bacteriocin translocation system., (© FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Micro-/nanofabrication-based lab-on-a-chip (LOC) technologies have recently been substantially advanced and have become widely used in various inter-/multidisciplinary research fields, including biological, (bio-)chemical, and biomedical fields. However, such hybrid-scale LOC devices are typically fabricated using microfabrication and nanofabrication processes in series, resulting in increased cost and time and low throughput issues. In this review, after briefly introducing the conventional micro-/nanofabrication technologies, we focus on unconventional micro-/nanofabrication technologies that allow us to produce either in situ micro-/nanoscale structures or master molds for additional replication processes to easily and conveniently create novel LOC devices with micro- or nanofluidic channel networks. In particular, microfabrication methods based on crack-assisted photolithography and carbon-microelectromechanical systems (C-MEMS) are described in detail because of their superior features from the viewpoint of the throughput, batch fabrication process, and mixed-scale channels/structures. In parallel with previously reported articles on conventional micro-/nanofabrication technologies, our review of unconventional micro-/nanofabrication technologies will provide a useful and practical fabrication guideline for future hybrid-scale LOC devices.

We propose a see-through multi-projection three-dimensional (3D) display using a transparent anisotropic diffuser. By immersing a metal-coated anisotropic diffuser into index matching oil which has the same refractive index of anisotropic diffuser, a transparent anisotropic diffuser is implemented. The reflectance of the transparent anisotropic diffuser is analyzed with the transfer matrix. Two multi-projection methods are proposed based on reflection type integral imaging and multi-view method. Especially, the reflection type multi-view-based system is realized with a curved anisotropic diffuser. High resolution see-through 3D display can be realized with the proposed methods. They can be used in various applications with the two multi-projection methods. In order to show the augmented reality features, real objects and virtual 3D images are presented at the same time in the experimental setup.

Staphylococcus haemolyticus S167 has the ability to produce biofilms in large quantities. Genomic analyses revealed information on the biofilm-related genes of S. haemolyticus S167. Detailed studies of biofilm formation at the molecular level could provide a foundation for biofilm control research., (Copyright © 2016 Hong et al.)

In light field microscopy (LFM), the F-number of the micro lens array (MLA) should be matched with the image-side F-number of the objective lens to utilize full resolution of an image sensor. We propose a new F-number matching method that can be applied to multiple objective lenses by using an elastic MLA. We fabricate an elastic MLA with polydimethylsiloxane (PDMS) using a micro contact printing method and address the strain for the F-number variation. The strain response is analyzed, and the LFM system with the elastic MLA is demonstrated. Our proposed system can increase the F-number up to 27.3% and can be applied to multiple objective lenses.

Staphylococcus aureus is an important foodborne pathogen on global basis. The current study investigated the genetic patterns in S. aureus isolates from leaf vegetables (n = 53). Additional isolates from livestock (n = 31) and humans (n = 27) were compared with the leaf vegetable isolates. Genes associated with toxins, antibiotic resistance, and pulsed-field gel electrophoresis (PFGE) patterns were analyzed. At least 1 enterotoxin-encoding gene (sea, seb, sec, sed, and see) was detected in 11 of 53 (20.75%) leaf vegetable isolates. When the agr (accessory gene regulator) grouping was analyzed, agr II was the major group, whereas agr IV was not present in leaf vegetable isolates. All S. aureus isolates from leaf vegetables were resistant to more than one of the antibiotics tested. Nineteen of 53 (35.85%) isolates from leaf vegetables exhibited multidrug-resistance, and 11 of these were MRSA (methicillin-resistant S. aureus). A dendrogram displaying the composite types of S. aureus isolates from 3 origins was generated based on the combination of the toxin genes, agr genes, antibiotic resistance, and PFGE patterns. The isolates could be clustered into 8 major composite types. The genetic patterns of S. aureus isolates from leaf vegetables and humans were similar, whereas those from livestock had unique patterns. This suggests some S. aureus isolates from leaf vegetables to be of human origin., (© 2015 Institute of Food Technologists®)

The holographic wavefront printer decodes the wavefront coming from a three-dimensional object from a computer generated hologram displayed on a spatial light modulator. By recording this wavefront as an analog volume hologram this printing method is highly suitable for realistic color 3D imaging. We propose in the paper spatial partitioning of the spatial light modulator to perform mosaic delivery of exposures at primary colors for seamless reconstruction of a white light viewable color hologram. The method is verified for a 3 × 3 color partitioning scheme by a wavefront printer with demagnification of the light beam diffracted from the modulator.

Two-dimensional (2D) and three-dimensional (3D) transparent screens can be created using lens-array holographic optical elements (HOEs). Lens-array HOEs can be used to perform 2D and 3D imaging for Bragg matched images while maintaining the transparent properties of the images in the background scenes. 2D or 3D imaging on the proposed screen is determined by the relative size of an elemental-lens on the lens-array to a pixel on the projected image. The 2D and 3D displays on the lens-array HOEs are implemented by the diffusion of light on each elemental-lens and by taking advantage of reflection-type integral imaging, respectively. We constructed an HOE recording setup and recorded two lens-array HOEs having different optical specifications, permitting them to function as 2D and 3D transparent screens. Experiments regarding 2D and 3D imaging on the proposed transparent screens are carried out and the viewing characteristics in both cases are discussed. The experimental results show that the proposed screens are capable of providing 2D and 3D images properly while satisfying the see-through properties.

Three-dimensional profiling and tracking by digital holography microscopy (DHM) provide label-free and quantitative analysis of the characteristics and dynamic processes of objects, since DHM can record real-time data for microscale objects and produce a single hologram containing all the information about their three-dimensional structures. Here, we have utilized DHM to visualize suspended microspheres and microfibers in three dimensions, and record the four-dimensional trajectories of free-swimming cells in the absence of mechanical focus adjustment. The displacement of microfibers due to interactions with cells in three spatial dimensions has been measured as a function of time at subsecond and micrometer levels in a direct and straightforward manner. It has thus been shown that DHM is a highly efficient and versatile means for quantitative tracking and analysis of cell motility.

A novel system of optical see-through augmented reality (AR) is proposed by making use of a holographic optical element (HOE) with full-color and lens-array functions. The full-color lens-array HOE provides see-through property with three-dimensional (3D) virtual images, for it functions as a conventional lens array only for Bragg-matched lights. An HOE recording setup was built, and it recorded a 30 mm × 60 mm sized full-color lens-array HOE by using the techniques of spatial multiplexing for large-area recording and wavelength multiplexing for full-color imaging. The experimental results confirm that the suggested full-color lens-array HOE can provide the full-color 3D virtual images in the optical see-through AR system.

We propose a two-dimensional (2D) and three-dimensional (3D) convertible bi-sided integral imaging. The proposed system uses the polarization state of projected light for switching its operation mode between 2D and 3D modes. By using an optical module composed of two scattering polarizers and one linear polarizer, the proposed integral imaging system simultaneously provides 3D images with 2D background images for observers who are located in the front and the rear sides of the system. The occlusion effect between 2D images and 3D images is realized by using a compensation mask for 2D images and the elemental images. The principle of proposed system is experimentally verified.

We propose a single-shot incoherent holographic imaging technique that adopts self-interference incoherent digital holography (SIDH) with slight tilt of the plane mirror in the optical configuration. The limited temporal coherence length of the illumination leads the guide-star hologram of the proposed system to have a Gaussian envelope of elliptical ring shape. The observation shows that the reconstruction by cross correlation with the guide-star hologram achieves better quality than the usual propagation methods. Experimentally, we verify that the hologram and 3D reconstruction can be implemented incoherently with the proposed single-shot off-axis SIDH.

In a typical auto-stereoscopic three-dimensional display, the parallax barrier or lenticular lens is located in front of the display device. However, in a projection-type auto-stereoscopic display, such optical components make it difficult to display elemental images on the screen or to reconstruct a three-dimensional image, even though a projection-type display has many advantages. Therefore, it is necessary to use a rear projection technique in a projection-type auto-stereoscopic display, despite the fact that this is an inefficient use of space. We propose here a frontal projection-type auto-stereoscopic display by using a polarizer and a quarter-wave retarding film. Since the proposed method uses a frontal projection scheme and passive polarizing components, it has the advantage of being both space saving and cost effective. This is the first report that describes a frontal projection-type auto-stereoscopic display based on a parallax barrier and integral imaging by using a projector. Experimental results that support the proposed method are provided.

Novel integral floating three-dimensional (3D) display methods are proposed for implementing an augmented reality (AR) system. The 3D display for AR requires a long-range focus depth and a see-though property. A system that adopts a concave lens instead of a convex lens is proposed for realizing the integral floating system with a long working distance using a reduced pixel pitch of the elemental image. An investigation that reveals that the location of the central depth plane is restricted by the pixel pitch of the display device is presented. An optical see-through system using a convex half mirror is also proposed for providing 3D images with a proper accommodation response. The concepts of the proposed methods are explained and the validity of system is proved by the experimental results.

Two novel methods are proposed which enhance the angular sampling rate of the integral floating display by adopting dynamically variable apertures in front of the lenslet array or the floating lens. Adopted dynamically variable apertures are opened sequentially in synchronization with proper elemental images to subdivide the angular sampling step by time-multiplexing method. Our proposed method can enhance the angular sampling rate, which is related to an expressible longitudinal range, without sacrificing other visual quality factors in tradeoff relationship. Especially, our proposed method with apertures on the floating lens provides two-dimensional/three-dimensional convertible feature to integral floating display system., (© 2012 Optical Society of America)

Recent trends in three-dimensional (3D) display technologies are very interesting in that both old-fashioned and up-to-date technologies are being actively investigated together. The release of the first commercially successful 3D display product raised new research topics in stereoscopic display. Autostereoscopic display renders a ray field of a 3D image, whereas holography replicates a wave field of it. Many investigations have been conducted on the next candidates for commercial products to resolve existing limitations. Up-to-date see-through 3D display is a concept close to the ultimate goal of presenting seamless virtual images. Although it is still far from practical use, many efforts have been made to resolve issues such as occlusion problems., (© 2011 Optical Society of America)

In three-dimensional television (3D TV) broadcasting, we find the effect of fundamental depth resolution and the cardboard effect to the perceived depth resolution on multi-view display is important. The observer distance and the specification of multi-view display quantize the expressible depth range, which affect the perception of depth resolution of the observer. In addition, the multi-view 3D TV needs the view synthesis process using depth image-based rendering which induces the cardboard effect from the relation among the stereo pickup, the multi-view synthesis and the multi-view display. In this paper, we analyze the fundamental depth resolution and the cardboard effect from the synthesis process in the multi-view 3D TV broadcasting. After the analysis, the numerical comparison and subjective tests with 20 participants are performed to find the effect of fundamental depth resolution and the cardboard effect to the perceived depth resolution.

We propose a new method for implementing 3D/2D convertible feature in the projection-type integral imaging by using concave half mirror array. The concave half mirror array has the partially reflective characteristic to the incident light. And the reflected term is modulated by the concave mirror array structure, while the transmitted term is unaffected. With such unique characteristic, 3D/2D conversion or even the simultaneous display of 3D and 2D images is also possible. The prototype was fabricated by the aluminum coating and the polydimethylsiloxane molding process. We could experimentally verify the 3D/2D conversion and the display of 3D image on 2D background with the fabricated prototype.

We propose a new method for rectifying a geometrical distortion in the elemental image set and extracting an accurate lens lattice lines by projective image transformation. The information of distortion in the acquired elemental image set is found by Hough transform algorithm. With this initial information of distortions, the acquired elemental image set is rectified automatically without the prior knowledge on the characteristics of pickup system by stratified image transformation procedure. Computer-generated elemental image sets with distortion on purpose are used for verifying the proposed rectification method. Experimentally-captured elemental image sets are optically reconstructed before and after the rectification by the proposed method. The experimental results support the validity of the proposed method with high accuracy of image rectification and lattice extraction.

A depth-enhanced three-dimensional-two-dimensional convertible display that uses a polymer-dispersed liquid crystal based on the principle of integral imaging is proposed. In the proposed method, a lens array is located behind a transmission-type display panel to form an array of point-light sources, and a polymer-dispersed liquid crystal is electrically controlled to pass or to scatter light coming from these point-light sources. Therefore, three-dimensional-two-dimensional conversion is accomplished electrically without any mechanical movement. Moreover, the nonimaging structure of the proposed method increases the expressible depth range considerably. We explain the method of operation and present experimental results.

An optical depth converter that uses a lens array pair is analyzed theoretically and experimentally. We present a theory of depth conversion and explain the effects of the system parameters in the optical depth converter by using wave-optical analysis. Ray-optical analysis is applied to the investigation of the tendencies of the system parameter effects. We also show that the optical depth converter can be used for the three-dimensional screen in projection-type integral imaging systems.

The image depth of integral imaging is enhanced by doubling the number of central depth planes by use of optical path control. To accomplish this, the optical path lengths are changed by controlling whether reflections occur behind the lens array. We propose three schemes that use mirrors, a combination of beam splitters and polarizers, and polarization beam splitters, respectively. In experiments we implement the systems that are completely electronically controllable, are compact, and provide two central depth planes with 50.4-mm separation.