Evaluation of NDVI (Normalized Difference Vegetation Index) derived from a combination of two digital camera images with/without near-infrared lens filter was made by comparing with the NDVI processed from a multi-spectral data of an Earth Observation Satellite, ‘Quickbird'. It was pointed out the importance of the AE (automatic exposure) function of the digital camera and a lens filter blocking infrared light when preparing near infrared and visible red images for derivation of the vegetation index. Results of calculated NDVI from the digital camera images with two filters blocking either visible red light or infrared light were satisfactorily coincident with the NDVI values measured by a spectrophotometer. It was speculated that the primary factor of the difference in histograms of NDVI distribution maps between values from digital camera images and those from the satellite data would be attributed to difference of meteorological conditions anterior to the date of observation.
Negatively charged electrophoretic TiO2 particles (white) and positively charged electrophoretic titan black particles (black) were prepared via two step chemical reactions, (1) modification of TiO2 or titan black particles with silane coupling agent having polymerizable moiety, and (2) graft polymerization of hydrophilic monomers in the presence of modified particles. Characteristics of electrophoretic single particle image display containing dispersion of white particles in blue dyed Isopar G was highly influenced by electrophoretic mobility of the particles. Image display using white particles of higher mobility exhibited better optical responses. On the contrary, electrophoretic dual particle image display containing dispersions of white and black particles of high mobility being charged with opposite polarity exhibited poor optical responses. In this setup, the combination of black particles of high mobility and white particles of low mobility exhibited good optical responses. As white and black particles of high mobility with opposite polarity supposed to coagulate each other to reduce their mobility, the combination of these particles couldn't improve optical responses of electrophoretic dual particle image display.
In drop-on-demand inkjet systems, nozzle clogging due to evaporation is our great concern. To study the drying process at the inkjet nozzle, we have developed a novel method for measuring the change of ink viscosity at the nozzle. In this method, ink viscosity is estimated by measuring the vibration of meniscus using a laser Doppler vibrometer and by verifying the measured results with calculations using an equivalent circuit model of inkjet head. In order to understand the drying process, the changes of viscosity by the evaporation about a glycerol aqueous solution were simulated by a one-dimensional convective diffusion model and compared with the experimental results of viscosity measurements. The results of simulation show good agreement with experimental results. Thus, the drying process of simple liquid can be expressed well by the model. From the experimental and simulation results, it was revealed that the drying process shows two-step process;the drying process of the surface at the nozzle and the drying process of the pressure chamber.
Thermal paper is a functional paper, which can develop color images by thermal reaction of dye and developer. One major problem of the thermal paper is that when exposed to UV light, photodecomposition of leuco dye proceeds and yellowish coloration and image fading occurs. In order to improve its durability against light (lightfastness), novel cinnamic amide derivatives which posses' UV-absorbent ability was employed as a developer. By using the selected derivatives, we succeeded to realize a thermal paper that exhibits excellent lightfastness in both background and image. To afford lightfastness by using cinnamic amide derivatives, the developer's photostability is also needed. And by crystal structure analyses, the derivative showing low photostability proceeds solid state [2+2] photodimerization by UV irradiation, which decreases UV absorbing ability of the compound.
History of ink jet research and development is reviewed briefly. In this review, marking principles and features of each ink jet systems are described. Next, introduced new technologies since 1980s to improve fundamental performances of ink jet printer or resolve issues imposed on ink jet and the background are summarized. Ink jet with simple process is categorized as the concentrated functional marking, under this model, ink jet has developed and extended market depending performance progress of elemental technologies. However performance progress of elemental technologies has been dulled recently, noticeable growth of ink jet is unhopeful in the same old direction under same model. 2 paths exist for ink jet growth in the future. One is expansion of ink jet to various applications where ink jet can continue to provide values with using simple process under same model. The other is marking model conversion to shared functional marking model. Namely, ink jet will add peripheral technologies and share approaches to high level issues among these peripheral technologies.
According to the investigation of the Ministry of Economy, Trade and Industry, the rate of offset printing to the whole printing in 2009 is 75%. On the other hand, the beginning of the history of an offset method is an invention of I. W. Rubel (the United States) in 1904 or development of domestic technology in 1914, so the history is the lately technology compared with others. The offset printing qualities could be compatible in characters and pictures, and since it was suitable for mass production of color printing, the technology has progressed rapidly. The technology has mostly matured in the time of environmental correspondent production after mass and stable production. Offset printing technology has been supported on some technologies such as an improvement of the domestic printing machine which continues from 1914, the development of plate material and CTP system, and CMS technology. From now on, it is considered that the technical development will progress in the field of QCD, environment, the diversion to the packaging and industrial material which have a large merit by standardization.
Electrophotography has been continued to be a primary printing method in the office work for more than 70 years since its invention. In this paper, technical or historical factors are reviewed which has contributed to the successful survival of electrophotography through the critical periods of change to digitalization and colorization. Electrophotography is a sequence of transduction process of physical quantities utilizing a photoconductive effect from original image information to a reproduction on plain paper. Many engineers have been fascinated with the neatness of the process and have produced many improving innovations. Through the representative epochs such as  invention of cartridge system, responsibility to digitalization, colorization and  penetration to the POD (Print on Demand) business, its ground has been expanded from the personal use to the manufacturing facility industry as well as a key to effectiveness of office activities. Liquid development method has been coexisted alongside the dry process and has continued a unique improvement up to the present. In the rapid transition of document management to the electronic media, technical improvement of electrophotography is further expected as a frontier to a new region with changing value of output on paper media.
The printing process of an impact printer is very simple and primitive method that is impacting with a hammer and so forth to printing media through dyeing material, such as an ink ribbon or carbon copy paper. And the dot matrix type which impact with the tip of a wire and form character and figure by the aggregate of the dot is major method in impact printer. In spite of the other excellent printing processes developed now, it is still supported with the demand of business, such as check printing, because the printing method of the copy generated is simple and reliable using carbon copy paper. For the reason, technical improvement in the realm of medium handling and user-friendliness is advanced supposing business, such as check printing in the counter work. In this technical description, it is explained focusing on the print head (wire dot impact head) which is the core technology in printer.
A direct thermal recording method has advantages over conventional recording procedures. These advantages result from the feature of a direct thermal recording material which can generate color by synthesizing dye in response to heat. There is, therefore, no need for ink, toner or developing solution. As a result, it can build small, light, simple and reliable recording system, and the thermal printer has been built into a cash register, a ticket machine, a facsimile, etc. Value-added direct thermal printers like a full-color thermal printer were also developed in latest 20 years. However, many of them were not accepted in the market, because these printers and materials were too complex and loose simplicity.
In recent years, market demand for high quality and value-added image printing has been increasing, along with digital device updates and large capacity of data. Thermal transfer technology enables compact and low cost print system with its simple printing method. Because of these advantages, thermal transfer technology is well recognized as a suitable system for on-demand dry printing. This paper explains the basic method and application of the two thermal transfer technology, dye sublimation thermal transfer and mass transfer.
Thermal rewritable marking media are now attracting attention because of their low environmental impact and advanced functionality. Various rewritable technologies have been developed 1980' s to 1990' s. These technologies can be divided into two types : a rewritable method by a physical mechanism and a rewritable method by a chemical mechanism. Physical type is high durability and chemical type is high contrast. Polymer dispersed with long chain molecules for physical type and leuco dye/long chain developer for chemical type were used practically, because the control between image formation and deletion which change only by differences of temperatures was simple. It was also important that market of display on card expanded at the same time. I will introduce the technology utilized to erasable ink, and the technologies using liquid crystals and photochromizm that were not utilized for rewritable marking.