To understand electrophotography, the history and the current position and roles in print eco-system is discussed. For technologies, an overview of the electrophotographic system is explained at first. Afterwards, the direction and the recent progress of the electrophotographic technologies are described. The category “light production” is the mainstream of recent electrophotographic printers. The direction for the growth is improvement to higher speed range for heavy duty use with low cost in the color electrophotographic printers. Recent progresses of the technologies are mainly achieved toward higher image quality and stability and extending media varieties. They are supported by “vertical cavity surface emitting laser,” high-speed image processing technologies, longer and flat nip fusers, and transfer technologies for deep patterned indented surface media, thick and thin media, and envelop. As a result, electrophotography catches up with the offset printing in transaction use. These improvements will continue in the future. Using the advantage of antiweatherability, label and/or package printing are expected for the future electrophotography.

Digital textile printing (DTP) is fast, flexible, and relatively inexpensive for sample printing, and can be applied quickly in response to consumer demand. The aim of this two-stage research was to analyze the potential of DTP to replace traditional screen printing for a specific textile product. In Stage One, an optimal DTP workflow was established. The workflow included determination of the colorant and substrate combination, color calibration, CAD file, and the necessity of pretreatment. In Stage Two, a visual assessment instrument and protocol were established to evaluate the acceptance of replicated ink-jet printed fabric. The visual assessment and protocol were designed to evaluate the acceptance of the ink-jet printed sample to fully replicate the screen-printed sample via seven measured aspects. These seven aspects include: perceived color difference, lightness difference, overall color, scale, line quality, visual texture, and overall appearance. Data gathered from the visual assessment was then analyzed and compared using SPSS statistics software. The results indicate that DTP demonstrates a significant potential alternative for traditional screen printing.

Relatively recent advancements in 3D printing include the ability to print with multiple materials and in multiple colors. Traditional 2D printers, which print to flat media, assume that the surface geometry has a negligible effect on the appearance. The International Color Consortium (ICC) builds profiles allowing for color communication among devices, including traditional 2D printers. The ICC does not currently have practices in place to build profiles for color 3D printers due, in part, to several unknown parameters affecting the appearance of 3D printed objects. One such unknown parameter is the surface structure. To test the effect of surface structure on the color appearance of 3D printed objects, 3D models were built digitally with goniochromatic effects in mind and then printed using a color 3D printer. Spectral radiance and bidirectional reflectance distribution function measurements of the 3D printed samples were taken and correlated with the results of a psychophysical experiment to test for changes in the appearance. It was found that surface structure does have a measurable, perceptible effect on the color appearance of 3D printed objects.

Different whiteboard image degradations highly reduce the legibility of pen-stroke content as well as the overall quality of the images. Consequently, different researchers addressed the problem through different image enhancement techniques. Most of the state-of-the-art approaches applied common image processing techniques such as background foreground segmentation, text extraction, contrast and color enhancements and white balancing. However, such types of conventional enhancement methods are incapable of recovering severely degraded pen-stroke contents and produce artifacts in the presence of complex pen-stroke illustrations. In order to surmount such problems, the authors have proposed a deep learning based solution. They have contributed a new whiteboard image data set and adopted two deep convolutional neural network architectures for whiteboard image quality enhancement applications. Their different evaluations of the trained models demonstrated their superior performances over the conventional methods.

In September 2017, the first author suffered a rhegmatogenous retinal detachment. This experience included a series of remarkable, sometimes unsettling visual phenomena, which included visible differences in the color vision between her two eyes during the recovery from retinal detachment, as a cataract developed, and following cataract surgery. Her right eye is now equipped with a new lens, replacing one that had yellowed from years of exposure to ultraviolet radiation, which provides a cooler view of the world than before retinal detachment, with slight distortions, and occasionally with sparkles early in the morning. In this review, the color vision changes that were experienced are quantified and detailed. While this does not represent a typical study with a hypothesis and testing of various participants, we hope that it inspires others to ask interesting questions that lead to increased consideration of the relationships between perception and visual health and that it raises awareness of the warning signs of retinal detachment.

In this study, we propose a method to detect wetness on the surface of human skin and skin phantoms using an RGB camera. Recent research on affect analysis has addressed the non-contact multi-modal analysis of affect aimed at such applications as automated questionnaires. New modalities are needed to develop a more accurate system for analyzing affects than the current system. Thus we focus on emotional sweating, which is among the most reliable modalities in contact methods for affect analysis. However, sweat detection on the human skin has not been achieved by other researchers, and thus it is unclear whether their feature values are useful. The proposed method is based on feature values of color and glossiness obtained from images. In tests of this method, the error rate was approximately 6.5% on a skin phantom and at least approximately 12.7% on human skin. This research will help to develop non-contact affect analysis.

Under specular reflection, non-isotropic halftones such as line halftones printed on an ink-receiving plastic layer superposed with a metallic layer change their colors upon in-plane rotation of the print. This color change is due to the orientation-dependent optical dot gain of the halftone. A strong dot gain occurs when the incident light is perpendicular to the halftone line structure. A color prediction model is proposed which predicts under specular reflection the color of cyan, magenta and yellow line halftones as a function of the azimuthal rotation angle, the incident angle and the line frequency. The model is calibrated by measuring 17 reflectances at the (25∘:25∘) measurement geometry, with the incident light parallel to the halftone lines. The model has been tested for several azimuthal rotation and incident viewing angles, each time for 125 different cyan, magenta and yellow ink surface coverages. The obtained prediction accuracies are between ΔE₉₄ = 3.5 and ΔE₉₄ = 7.

The present study shows fabrication of electronic resistor by means of inexpensive inkjet printing method on the photonic paper substrate at room temperature. The objective of this work is to demonstrate the feasibility of the inkjet printed resistor with different resistance values for the application of electronic devices. Inkjet printing process is performed using magnetostrictive inkjet printhead designed by our laboratory which use a magnetostrictive material, Terfenol-D rod as an actuation mechanism. For printing resistor component on the photonic paper substrate, we use two functional inks: one is the silver nanoparticle ink, which is used to make conducting layer, the other one is poly (3,4-ethylene dioxythiophene): poly (styrene sulfonate) (PEDOT:PSS) ink, which is used to make resistive layers. The resistivity of the printed resistor is altered with different resistance values with respect to the printing layers, different ink formulations, and length of the resistor line. An electronic circuit is sketched and tested using fabricated resistor component. The printed resistor with various resistance values provides an important building block for low cost, printed electronic circuit application. From these results, we can show that magnetostrictive inkjet printhead has a potential to fabricate electronic devices.

The alternating current electroluminescent (ACEL) device is ideally suited for flat light emitting owing to its particular properties, compactness, robustness, and flexibility. In this article, six types of white electroluminescent devices containing red fluorescent dyes as light-conversion materials in different position were fabricated by spin coating, controlling the thickness of layers accurately. The luminance, efficiency, light emission spectra and CIE coordinates of devices were investigated. The results show that the performance of the devices significantly depends on the position of the light-conversion layers, and the hybrid structure has excellent performance with the highest luminance. From the findings of this study, a practical and promising method is derived to optimize both the efficiency and luminance of conventional devices, and it makes sense for the latest color convertors such as quantum dots and perovskites in LEDs.