connected to a monitor. The tip of the light pen contains a lig ht-s ensit ive element which detects the light from the screen enabling the computer to identify the location of the pen on the screen. Light pens Figure . Fingerprint Scanner Figure .
Track Ball Figure . Light Pen movement of the cursor on the display screen. It can be used to select icons, menus, command buttons or activate something on a computer. Some mouse actions are move, click, double click, right click, drag and drop.
Different types of mouse available are: Mechanical Mouse, Optical, Laser Mouse, Air Mouse, 3D Mouse, Tactile Mouse, Ergonomic Mouse and Gaming Mouse. Who invented Mouse? The computer mouse as we know it today was i n v e n t e d and developed by Douglas Engelbart, with the assistance of Bill English, during the 's and was patented on November , . ( ) Scanner: Scanners are used to enter the information directly into the c o m p u t e r ’ s memory.
This device works like a Xerox machine. The scanner converts any type of printed or written information including photographs into a digital format, which can be manipulated by the computer. ( )Fingerprint Scanner: Finger print Scanner is a fingerprint recognition device used for computer security, equipped with the fingerprint recognition feature that uses biometric technology. Figure .
Scanner have the advantage of ‘drawing’ directly onto the screen, but this becomes hard to use, and is also not accurate. ( ) Optical Character Reader: It is a device which detects characters printed or written on a paper with OCR, a user can scan a page from a book. The Computer will recognise the characters in the page as letters and punctuation marks and stores. The Scanned document can be edited using a wordprocessor.
( ) Bar Code / QR Code Reader: A Bar code is a pattern printed in lines of different thickness. The Bar code reader scans the information on the bar codes transmits to the Computer for further processing. The system gives fast and error free entry