Curvature detection is important particularly in shape representation and object detection. Curvature contains information related to the features of an object, and a specific object can be extracted from an image so long as the features of the borderline can be determined from its curvature. Besides, accurate curvature detection can make applications such as checking of objects possible and industrial applicable. This paper proposes a novel mechanism for edge segment based curvature detection : a Laplacian and Gaussian (∇2G) filter is applied to an input image, and edge segments of the image are detected first ; By searching for peaks in positive and negative ∇2G values obtained from the edge segments, the borderline of an object in edge-segment units can be easily obtained, and the curvature can be simultaneously detected from the peak distance. With this method, high accurate curvature detection can be realized, and the feature shape of edge segments can be classified. A real life case study also demonstrates the feasibility and usefulness of the proposed method.
The vertical-type Metal-Base Organic Transistor (MBOT) with a simple layered structure exhibits a high current-modulation under low driving voltage. In this paper, we have improved the On/Off ratio of MBOT, and analyzed the frequency response characteristics. More than 105 of On/Off ratio was attained by heating at 150°C in the atmosphere after aluminum base electrode deposition. The frequency response depended on the capacitance between base and emitter electrodes, and the frequency of transition (fT) was estimated over 200 kHz, which was higher than that of generally known lateral organic transistors. We proposed an analysis model of electrical characteristics of MBOT that indicates the maximum fT could be the order of megahertz.
Brother Industries uses cleanerless system with nonmagnetic single component toner for monochrome laser printer products. The cleanerless system is useful for downsizing process cartridge because it does not need much space around post-transfer process. In monochrome laser printer HL2040, we tried space saving by using the cleanerless system and downsizing of many parts in all area of the machine. However, this cleanerless system needed stabilization of high toner transfer efficiency in all environmental conditions and to solve image quality issue that comes from paper dust adherence on photoconductor surface. This paper introduces some contraptions for downsizing of the machine and countermeasures to make possible the cleanerless system in small monochrome laser printer.
There has been a variety of EP (Electro Photography) systems in the on-demand printing market. It has been considered to be difficult to achieve the same quality as the Offset print, because the EP system has a different type of media, materials and process from the Offset printing. In the following, we will introduce techniques about imagePRESS C7000VP, which result in the improvement of image quality, stability, productivity and media flexibility. “The 50th 2007 10big new product, Masuda award (Nikkan Kogyou Shinbun)” was awarded to imagePRESS C7000VP.
Super-high speed continuous feed B/W laser printers are used for mission critical printing tasks in corporate and government offices. Very high volume printing jobs are printed in any printing occasions including peak tasks. Therefore, productivity in printing is the most important and very high-speed, durability and reliability are required for the printers. In this report, overview for the printers is described. Then, optical, developing and fuser systems, which give significant affection to imaging process technological concepts for the system productivity, durability and reliability, are explained in detail. In optical system, technologies for multi-beam scanning in wide and high-speed printing are explained. In developing system, imaging technologies for obtaining high image quality and durability are described and harmonized developer mixing method with the imaging is explained. Finally, fuser system in super high-speed printing for supplying sufficient fusing energy in very short period and technology for correcting continuous paper meandering are introduced.
In recent years, development of higher-speed xerographic printers and color technology has advanced rapidly and its application to the high-end and high-volume printing industry such as newspaper and service bureau business has accelerated. This market is very attractive. To respond to this customer demand, Fuji Xerox has developed the world's highest speed full-color printing system employing Flash Fusing technology : “Fuji Xerox 490/980 Color Continuous Feed Printing Systems” (hereafter called “490/980 CCF”). In this paper, the following sections describe the design concept and major technologies employed in this system.
Demands to life improvement of organic photoreceptor enhance in the electrophotograph system, therefore research and development are further done actively. In particular electrostatic property performance and the latent image reproduction performance that are high stability of organic photoreceptor are big subjects in the development of a long life organic photoreceptor. We suggest optimization of system design, and the layer composition of organic photoreceptor, and the protection layer to contain fine particles (FRL), and the new hole transport materials which have acid scavenge function (AS donor) for these subjects. By this report, we introduce life improvement technologies of organic photoreceptor in Ricoh.