CGH calculation algorithm for expressing reflection on a curved mirror surface.

Rendering techniques are important in computer-generated holograms (CGHs) for expressing various types of holo-realistic 3D images. Rendering techniques such as hidden surface removal and reflection by a planar mirror have been proposed thus far, but reflection on a curved mirror surface has yet to be achieved. In this study, we propose a calculation algorithm that can express the reflection of the surrounding environment on a mirror surface defined as a Bézier surface.

Stability of Sodium Pentobarbital 5w/v% Aqueous Solution During Short-Term Chilled and Ambient-Temperature Storage.

The COVID-19 pandemic made it difficult to obtain pharmaceutical-grade injectable anaesthetics used in animal experiments in Japan. To address this problem, it is worth the effort to evaluate whether the use of non-pharmaceutical-grade sodium pentobarbital (PBNa) water solution can be an alternative one from the perspective of stability, physicochemical properties, bioavailability and so on. In this article, as a first step, we examined the stability of PBNa 5w/v% aqueous solution (PBNa 5% AS).

Realistic rendering method for specular reflections with continuous motion parallax in a computer-generated hologram.

A computer-generated hologram (CGH) enables the display of virtual images and videos as well as the communication and storage of holographic data. The point-based method, which is a CGH-calculation method for representing the surface of an object as a set of point-light sources, has not been sufficiently studied in terms of realistic representation. This paper proposes a CGH-calculation method for realistic rendering using ray tracing to be used with a point-based method.

Enlargement of the viewing zone and size of a reconstructed image in electro-holography using multiple reconstruction lights by eye-tracking.

To solve the problem of the narrow viewing zone in electro-holography, we propose a method using eye-tracking and a property of holography where the viewing zone varies with the angle of the reconstruction light. The method can enlarge the viewing zone without moving the optical elements for higher-order diffracted light removal and high-refresh-rate devices. The size of the reconstructed image is also enlarged using lenses.

Method of calculating speckle-reduced hologram data using a convergence light wave for a computer-generated hologram.

In a computer-generated hologram, random phases are required for representing object surfaces; however, speckle noise occurs in the random phases. We propose a speckle reduction method for three-dimensional virtual images in electro-holography. The method does not have random phases but instead converges the object light on the observer's viewpoint.

Fast calculation method based on hidden region continuity for computer-generated holograms with multiple cameras in a sports scene.

We propose, to the best of our knowledge, the world's first system capable of fast calculating computer-generated holograms (CGHs) from a large-scale outdoor sports scene captured with multiple RGB cameras. In the system, we introduce a fast calculation method focusing on hidden region continuity (HRC) that frequently appears in a point cloud of a 3D sports scene generated from free-viewpoint video technology. The experimental results show that the calculation time of the proposed HRC method is five to 10 times faster than that of the point-based method, which is one of the common CGH calculation methods.

Corneal protective effects of novel tear substitutes containing sodium hyaluronate and dodecahydrosqualene, squalane, in a porcine dry eye model.

To develop a novel tear substitute (TS) containing sodium hyaluronate (SH) and dodecahydrosqualene (DHS, squalane), we improved the prescription of a previously developed TS containing saline, 0.5% SH and 1% castor oil (CO), which had corneal protective effects against 60-min desiccation in a porcine dry eye model and viscosity of 106.8 mPa·S.

Radiometric Calibration for a Multispectral Sensor Onboard RISESAT Microsatellite Based on Lunar Observations.

Radiometric calibration utilizing the Moon as a reference source is termed as lunar calibration. It is a useful method for evaluating the performance of optical sensors onboard satellites orbiting the Earth. Lunar calibration provides sufficient radiometric calibration opportunities without requiring any special equipment, and is suitable for nano/microsatellites.

Sensitizer-host-annihilator ternary-cascaded triplet energy landscape for efficient photon upconversion in the solid state.

In this paper, we introduce a new strategy for improving the efficiency of upconversion emissions based on triplet-triplet exciton annihilation (TTA-UC) in the solid state. We designed a ternary blend system consisting of a triplet sensitizer (TS), an exciton-transporting host polymer, and a small amount of an annihilator in which the triplet-state energies of the TS, host, and annihilator decrease in this order. The key idea underpinning this concept involves first transferring the triplet excitons generated by the TS to the host and then to the annihilator, driven by the cascaded triplet energy landscape.

Fast calculation method with saccade suppression for a computer-generated hologram based on Fresnel zone plate limitation.

The computer-generated hologram (CGH) is an ideal 3D technology that can satisfy all the physiological factors of the human eye (such as binocular parallax, focus adjustment and convergence etc.) by simulating the recording part of traditional optical holography with a computer. CGH has a lot of advantages such as being able to be used for animation.

Fast calculation method for viewpoint movements in computer-generated holograms using a Fourier transform optical system.

Augmented reality (AR) using a holographic head-mounted display has been attracting a great deal of attention. In the AR system, computer-generated holograms (CGHs) are calculated and displayed on an electronic display. However, the time required for making CGHs is very long.

Lossless compression applying linear predictive coding based on the directionality of interference patterns of a hologram.

This paper proposes lossless linear predictive coding based on the directionality of the interference patterns of a hologram. We approached this study from two aspects. First, to determine the directionality of the interference patterns, we performed differential pulse coding modulation (DPCM), segmenting interference patterns into blocks and scanning the pixels in eight directions for each block.

Fast calculation method with foveated rendering for computer-generated holograms using an angle-changeable ray-tracing method.

The computer-generated hologram (CGH) technique is a technique that simulates the recording of holography. Although the CGH technique has a lot of advantages, it also has some disadvantages; one of them is the long calculation time. Much research on the human eye has established that humans see 135° vertically and 160° horizontally, but can see fine detail within an only 5° central circle.

Holographic display method for volume data by volume rendering.

Volume data are widely used in many areas, especially in biomedical science and geology. Visualizing volume data is very important to enable intuitive understanding of 3D structures, making them easier to analyze. However, current visualization technologies for volume data cannot satisfy human requirements.

HPT: A High Spatial Resolution Multispectral Sensor for Microsatellite Remote Sensing.

Although nano/microsatellites have great potential as remote sensing platforms, the spatial and spectral resolutions of an optical payload instrument are limited. In this study, a high spatial resolution multispectral sensor, the High-Precision Telescope (HPT), was developed for the RISING-2 microsatellite. The HPT has four image sensors: three in the visible region of the spectrum used for the composition of true color images, and a fourth in the near-infrared region, which employs liquid crystal tunable filter (LCTF) technology for wavelength scanning.

Holographic display methods for volume data: polygon-based and MIP-based methods.

Volume data are widely used in many areas, especially in biomedical science and geology. However, current visualization technologies of volume data cannot satisfy the visual requirements of humans. In this study, we propose two holographic display methods for volume data.

Dynamic visual responses of accommodation and vergence to electro-holographic images.

Electro-holography can display images without inducing fatigue and three-dimensional (3D) sickness, i.e., visual discomfort due to viewing a stereoscopic display.

Fast calculation method of computer generated hologram animation for viewpoint parallel shift and rotation using Fourier transform optical system.

Computer generated hologram (CGH) animations can be made by switching many CGHs on an electronic display. Some fast calculation methods for CGH animations have been proposed, but one for viewpoint movement has not been proposed. Therefore, we designed a fast calculation method of CGH animations for viewpoint parallel shifts and rotation.

Response of accommodation and vergence to electro-holographic images.

Studies on measuring accommodation and vergence responses of human vision are important to evaluate three-dimensional (3D) display technologies. Electro-holography is expected to be an ideal 3D display. However, there has been little research on measuring responses to it.

Corneal-protective effects of an artificial tear containing sodium hyaluronate and castor oil on a porcine short-term dry eye model.

The corneal-protective effects of an artificial tear containing sodium hyaluronate (SH) and castor oil (CO) were evaluated on a porcine short-term dry eye model. Fresh porcine eyes with an intact cornea were treated with an artificial tear of saline, SH solution (0.1%, 0.

CGH calculation with the ray tracing method for the Fourier transform optical system.

Computer-generated holograms (CGHs) are usually displayed on electronic devices. However, the resolution of current output devices is not high enough to display CGHs, so the visual field is very narrow. A method using a Fourier transform optical system has been proposed, to enlarge the size of reconstructed images.

Production of cloned NIBS (Nippon Institute for Biological Science) and α-1, 3-galactosyltransferase knockout MGH miniature pigs by somatic cell nuclear transfer using the NIBS breed as surrogates.

Background: Nuclear transfer (NT) technologies offer a means for producing the genetically modified pigs necessary to develop swine models for mechanistic studies of disease processes as well as to serve as organ donors for xenotransplantation. Most previous studies have used commercial pigs as surrogates.

Method And Results: In this study, we established a cloning technique for miniature pigs by somatic cell nuclear transfer (SCNT) using Nippon Institute for Biological Science (NIBS) miniature pigs as surrogates.