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A graphics tablet (also digitizer, digital drawing tablet, pen tablet, digital art board) is a computer input device that enables a user to hand-draw images, animations and graphics, with a special pen-like stylus, similar to the way a person draws images with a pencil and paper. These tablets may also be used to capture data or handwritten signatures. It can also be used to trace an image from a piece of paper which is taped or otherwise secured to the tablet surface. Capturing data in this way, by tracing or entering the corners of linear poly-lines or shapes, is called digitizing. The device consists of a flat surface upon which the user may "draw" or trace an image using the attached stylus, a pen-like drawing apparatus. The image is displayed on the computer monitor, though some graphics tablets now also incorporate an LCD screen for a more realistic or natural experience and usability. Some tablets are intended as a replacement for the computer mouse as the primary pointing and navigation device for desktop computers. == History == The first electronic handwriting device was the Telautograph, patented by Elisha Gray in 1888. Elisha Gray is best known as a contemporaneous inventor of the telephone to Alexander Graham Bell. The first graphics tablet resembling contemporary tablets and used for handwriting recognition by a computer was the ''Stylator'' in 1957. Better known (and often misstated as the first digitizer tablet) is the RAND Tablet〔http://sophia.javeriana.edu.co/~ochavarr/computer_graphics_history/historia/〕 also known as the ''Grafacon'' (for Graphic Converter), introduced in 1964. The RAND Tablet employed a grid of wires under the surface of the pad that encoded horizontal and vertical coordinates in a small magnetic signal. The stylus would receive the magnetic signal, which could then be decoded back as coordinate information. The acoustic tablet, or ''spark tablet'', used a stylus that generated clicks with a spark plug. The clicks were then triangulated by a series of microphones to locate the pen in space. The system was fairly complex and expensive, and the sensors were susceptible to interference by external noise. Digitizers were popularized in the mid 1970s and early 1980s by the commercial success of the ID (Intelligent Digitizer) and BitPad manufactured by the Summagraphics Corp. These digitizers were used as the input device for many high-end CAD (Computer Aided Design) systems as well as bundled with PCs and PC-based CAD software like AutoCAD. Summagraphics also made an OEM version of its BitPad which was sold by Apple Computer as the ''Apple Graphics Tablet'' accessory to their Apple II. These tablets used a magnetostriction technology which used wires made of a special alloy stretched over a solid substrate to accurately locate the tip of a stylus or the center of a digitizer cursor on the surface of the tablet. This technology also allowed Proximity or "Z" axis measurement. The first home computer graphics tablet was the KoalaPad. Though originally designed for the Apple II, the Koala eventually broadened its applicability to practically all home computers with graphics support, examples of which include the TRS-80 Color Computer, Commodore 64, and Atari 8-bit family. Competing tablets were eventually produced; the tablets produced by Atari were generally considered to be of high quality. In 1981, musician Todd Rundgren created the first color graphics tablet software for personal computers, which was licensed to Apple as the Utopia Graphics Tablet System. In the 1980s, several vendors of graphics tablets began to include additional functions, such as handwriting recognition and on-tablet menus. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Graphics tablet」の詳細全文を読む スポンサード リンク
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