4) Various types of touch Screens and Explain how a Touch Sensitive Pad Works.
A graphics tablet (or digitizing tablet, graphics pad, drawing tablet is a computer input device that allows one to hand-draw images and graphics, similar to the way one draws images with a pencil and paper. These tablets may also be used to capture data or handwritten signatures.
A graphics tablet (also called pen pad or digitizer) consists of a flat surface upon which the user may "draw" an image using an attached stylus, a pen-like drawing apparatus. The image generally does not appear on the tablet itself but, rather, is displayed on the computer monitor. Some tablets however, come as a functioning secondary computer screen that you can interact with directly using the stylus.
Some tablets are intended as a general replacement for a mouse as the primary pointing and navigation device for desktop computers.
The first electronic handwriting tablet 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 Styalator in 1957. Better known (and often mis-stated as the first digitizer tablet) is the RAND Tablet 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.
Other graphics tablets a commonly known as spark or acoustic tablets, 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 PC's 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.
3) Different Mouse Types & Explain how to use a Mouse
A graphics tablet (or digitizing tablet, graphics pad, drawing tablet is a computer input device that allows one to hand-draw images and graphics, similar to the way one draws images with a pencil and paper. These tablets may also be used to capture data or handwritten signatures.
A graphics tablet (also called pen pad or digitizer) consists of a flat surface upon which the user may "draw" an image using an attached stylus, a pen-like drawing apparatus. The image generally does not appear on the tablet itself but, rather, is displayed on the computer monitor. Some tablets however, come as a functioning secondary computer screen that you can interact with directly using the stylus.
Some tablets are intended as a general replacement for a mouse as the primary pointing and navigation device for desktop computers.
The first electronic handwriting tablet 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 Styalator in 1957. Better known (and often mis-stated as the first digitizer tablet) is the RAND Tablet 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.
Other graphics tablets a commonly known as spark or acoustic tablets, 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 PC's 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.
3) Different Mouse Types & Explain how to use a Mouse
Mechanical mouse has a small hard rubber ball underneath that moves against two rollers as it's passed across a flat surface. Mechanical sensors detect the movement of the rollers as an 'x' and 'y' axis and the cursor on screen is moved accordingly.
Optomechanical mouse works on the same principal. The rollers have wheels on the end of them with evenly spaced holes. As the wheels spin, a light-sensitive optical device counts the number of holes that pass by and convert those numbers to an 'x' and 'y' axis.
Optical mouse is more accurate or precise and has no moving parts. It uses a laser to detect movement and has to be paired with a special pad or mat that has an embedded optical reference grid.
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